SOME .
i EXCHANGE
THE CHLQRiNfi

A STUDY OF THE KENETKS 0P

mmmmu Am mom»-
amcmus momma
momma

wwoWfiWJ;

Thais
RQTY

mcmGAN smite. uuws
James erhurs? Phefips
V1956

:IHESIS

.V’_ L

LIBRARY

Michigan State
University

 

1 mm 0? THE KINETICS W SCHE FORMATION AND ISUX‘OPE EXCHANGE
£8“)?st INVOLVING THE CHLORINE FLUORIDfiS

3.?

J ales Parkhm‘st. Phelps

£13313

Submitted to the School of ldvanced Graduate Studies of Michigan
sate University of Agriculture and Applied Science
in partisl fulfillment of the requirements
for the degree or

MTG! OP PHIIDSOPHY

mm: of Chemistry

1956

mum

The author wishes to express his sincere appreciation
to Professor He: T. Rogers for his guidance, interest, and
encomgenent throughout the course or the entire investi-
gation; to Dr. James G. Sternberg for his guidance during
'Dr. Rogers' absence as well as his assistance in treatment
or results; to Dr. John L. Speirs and Mr. Frank Bette for
their suggestions and aid in building equipment, and to
the Atomic Energy Connission for a grant subsidizing this
research.

W
W
W
flit-I-
it!
it

TABLE (F CONTENTS

Page

I. mmmIWCOOOOOOOOOOOOCOOOOCOOOCO0.00.0000...00.0.00....
II. mmICLL m w W FmoammOOOOOOOOOOOO0.0.0....

Production of the Chlorine P1uorides....................
ISOtOW mange RandomOOOOOOOCOOO.OOOOOOOOOOOOOOO...
ministry of Properties of the Chlorine Fluorides... ......

III. (HS-HANDLING, REACTION, 1ND CWN‘I'ING APPARATUS.............

Tm Gu-mng systémOOOOeoo0000000000000...0000000000
The 0‘8 Reaction chmmrsooeeoooooooeeoeo000000000000000
Th0 Gas cwnting CMbereeeeeeesoeeeeeeeeeeeeeeeeeeeeeee
Absorption00113."...uoo...u.......ou.ounun..."

I". TWE‘L 13?st W KINETICS AND EXCHANGE REACTIONS"...

mticaOOOOOOOOOOOOOOOCOCOCOOOOOOOOOOOOO0....0.0.0.0...

mtmpy Of Activation.0.00.00.00.00OOOOOOOOOOOOOOOOOOOOO
mum RmuomOOOOOOOOQOOOOOOO.OOOOOOOOOOOOOOOOOO...

V. THE CHLORINE TRIFIUORIDE-CMINE SISTM...................

muctionCOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO0.0.00.0...

Kateri‘lBOOOOOOOOOOOO0.000000...OOOOOOOOOOOOOOOOOOO...O.

Mme Proced‘neOOOOOOOOOOOOOO.OOOOOOOOOOOOOOOOOOOOOQO
mmge ResultsOOOOOOOOOOOOO0.0.0.0000...0.00.00.00.00.
Procedure for the Study of the Kinetics of Pomtion of

Chlorim Hmonuoridaeoeeeeeeeeeeeeeeeeeeeeeeeeeoeeee
mtica ResultaOoooosOOOooeeooe00000000000000.000000000

Discus81on0000000000000000.00....OOOOOOOOOOOOOOOOOOOOOOO

VI. THE 0mm; TRIPUJORIDE 1ND 0mm HONCELUORIDE SISTEL.

Ixthroatxctiorxeeeeeeeeeeeeeeeeeesoeeeeeeeeeeeeeeeeeeeeeeee
materials.eeeeeeeeeeeeeeeeeeeeeseeeeeeeeeeeeeeoeeeeoeese

Enhange Procod‘meOOOOOOOOOOOOOOOOOOOOOOOOOCOOOOOOOOOOOO

ResultBOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOCOCOO...

1

N

\0 VIP“)

9
12

15
16

20

20
2h
25

28

28
28
32
38

39
he
71
78

78
78
79
87

Discussj‘OOOOOOO.OOOOOOOOOOOOOOOOOOOOO0....OOOOOOOOOOOOOO 103
The Case for a Homogeneous Mechanism................. 108
The Case for a heterogeneous Mechamm............... 117
Fm consider‘tionsOOOOOOOOOOOOOOOCOOOOOO0.00....0.. 118

TABLE OF CMMS - Continued Page
“VII. THE CHI-(BIKE HONWORIDE-CHLORINE 81m"............... 121

IntmduCtioDOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO 121
Hateri‘laOOOOOOOOOOOOOOOOOOOOOOOOOIOOOOOOOOOOCO0.0.0... 121
Emmnge meadWOOOOOOOCOOOOOOOOOOOOOOOOOOOOOOOOOOOOO 121
Emma” ResultaOOOOOOOOOO.OOOOOOOOOOCOOOOOOOOO00...... 122
Discussion...00...0....OOOOOOOOOOOOOOOOOOOOOOOOOOCOOOO. 125

LBW CEEOOOOOOOOIOOOOOI...O...OOOOOOOOOOOOOOOOOOOOO0.... 129

mmmBOOOOOOOOOO0..0.00.00.00.00...00.0.0.0...OOOOOOOOOOOOOO 132

TAKE!

II
III

VII
VIII

to F1

t1

:5 5 5

LIST OF TABLES

Page

Equilibrium Constants for the Formation of Chlorine
Trifluorid.00.00......OOOOOOOOOOOOOOOOO......OOOOOOOOOOOOO

Properties of the Chlorine rluorides and Chlorine.........

Some Thermochemical Values for the Halogens and the
Chlorine Fluorides in the Gas Phase at 1 Atmosphere

PmSMOOOCOOOOOC......OOOOOOOOOOOOOOOOO.......OOOOCOOOOOO

Kp Values for the Equilibrium (c113). .-.-_-‘ 2cn,...........
Kinetics oi Chlorine Honoiluoride Formation it 2ho° c . . . . .
Kinetics of Chlorine Honofluoride Formation at 220° c.....
Kinetics of chlorine Honofluoride Formation at 180° c .

Homogeneous Exchange in the Chlorine Trifluoride-Chlorins
Monofluoride System at 203.h° C...........................

Homogeneous Exchange in the Chlorine Trifluoride-Chlorine
nononuoude system ‘t 2218.30 0000......OOOOOOOOOOOOOOOOOO

Homogeneous Exchange in the Chlorine Trifluoride-Chlorine

7
8

67
68
69

98

99

Honouuoride System ‘t 2hSOho COOOOOOOOOOOOOOOOOOOOOOOO... 100

Constants Arising From the Application of the Langmuir

momtion,h°tmm0OOOOOOCOOOOOOOOOOOOO....OOOOOOOOOOOOO. 101‘

Heterogeneous Euchange in the Chlorine Tritluoride-

cum Mononuorida Sfim at 2030ho COCOOOOOOOOOOOOOOO. 105

Heterogeneous Exchange in the Chlorine Trifluoride-

Chlorine hononuoride System it 22h.3° c. and 215° 0......106

Exchange in the ChlorineZHonotluoride-Chlorine System..... 12h

m Emma Result8000*000O.........OOOOOOOOOOOOOOOO0.... 126

vii

LIST (I FIGURES

FIGJRE Page
1. Schematic diagram of the exchange and gas-handling
apparatus for halogen fluoridCS........................... 10
2. Photograph of the exchange and gas-handling apparatus..... 11
3. Schematic diagram of the nickel reaction chamber.......... 13
h. Cross-section of the gas-counting chamber................. 13
5. Infrared absorption cell. 17
6. Ultra-violet 10 on. absorption cell 17
7 . Photograph of the infrared cell and the ultra-violet cell. 18
8. Ultra-violet absorption of fluorothene.......‘............. 19a
9. Chlorine trifluoride Spectrum 30
10. 61388.net» for chlorine productionee.................... 31
11. Radioactive chlorine erection. 33
12 . Activity of radioactive chlorine at various pressures . . . . . 3h
13. Spectrum of chlorine-fraction after distillation.......... 36
11:. Spectrum of chlorine trifluoride-fraction after
diatillation.............................................. 37
15. Calibration curve for Helicoid gauge hl
l6. Chlorine monofluoride fomation at 2h0° C................. 145
17. Chlorine monofluoride formation at 2h0° C................. 1:6
18. Chlorim monofluoride, formation at 2140‘) C................. h?
19. Chlorine monofluoride formation at 2h0° C................. 118
20. Chlorine monoflueride formation at 2ho° C 1:9
21. Chlorine monofluoride formation at 2ho° 0....... so

viii

LIST OF FIGURES - Continued

FIGURE Page
22. Chlorine monofluoride formation at 2h0o C................. 51
23. Chlorine monofluoride formation at 2200 C................. 52
2h. Chlorine monofluoride formation at 220° 0 53
25. Chlorine monofluoride formation at 2h0° C................. Sh
26. Chlorine monofluoride formation at 2h0° C................. 55
27. Chlorine monofluoride formation at 21100 C................. 56
28. Chlorine monofluoride formation at 2h0° C................. 57
29. Chlorine monofluoride formation at 2h0° C................. 58
3o. Chlorine monofluoride formation at 2ho° C 59
31. Chlorine monofluoride formation at 2h0° C................. 60
32. Chlorine nonofluoride formation at 180° C................. 61
33. Chlorine monofluoride formation at 180° C................. 62
3h. Chlorine monofluoride formation at 1800 C................. 63
3S. Chlorine monofluoride formation at 180° C................. 6h
36. Chlorine monofluoride formation at 1800 C................. 65
37. Arrhenius plot for chlorine monofluoride formation........ 70
38. Chlorine monofluorlde spectrum 80

39. Activity of radioactive chlorine monofluoride at various

press‘mGSOOOO....OOOOOOOOOOCOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO 81

‘hO. Spectrum of chlorine trifluoride separated from chlorine
monorluoridOCOOCC...0......O......O...‘......O.......0.... 83

141. Spectrum of chlorine monofluoride separated from chlorine
trifluoride..‘...........‘OOOOCQOO......O................. 81‘

1:2. Second calibration.curve for Helicoid gauge............... 85
143. Third calibration curve for Helicoid gauge................ 86

LIST OF FIGURES - Continued

FIGURE

hh.

Chlorine monofluoride-chlorine trifluoride exchange at

203 CCOOOOOOOOC0.00.00.00.000000000000.0......OOOOOOOOOOOO

hS. Chlorine monofluoride-ohlorine trifluoride exchange at

116.

147.

148.

119.

50.

51.

52.

53.

55.
56.

203 COOOOOOOOOOO0.0.0.0..........OOOOOOOOOOOOOOOOOO0.0.0..

Chlorine monofluoride-chlorine trifluoride exchange at

203 00............IOOOOOOOOOOCOOOOOO......OOOOOOOOOOOOOOOO

Chlorine monofluoride-chlorine trifluoride exchange at

203° 0.0.0.0000...0.00.00.00.00...0.00.0000.........OOOOOO.

Chlorine monofluoride-chlorine trifluoride exchange at

22h o c.0000.........OOOOOOOOOOOOO.......OOOOOOOIOCOOOOOOO

Chlorine monofluoride-chlorine trifluoride exchange at

22h o COO.........OOCOOO......OOOOOOOOOOOOO......OOOOOOOOO

Chlorine monofluoride-chlorine trifluoride exchange at

2&5 COOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO.00.0.0000...

Chlorine monofluoride-chlorine trifluoride exchange at

2165 COOOOOOCOOOOOOOO0.000.000.0000.....OOOOOOOOOOOOOCOOO

Arrhenius plot for chlorine monofluoride-chlorine tri-

Page

89

9O

91

92

93

9h

95

96

fluoride exchange: homogeneous mechanism.................. 101

Arrhenius plot for chlorine monofluoride-chlorine tri-

fluoride exchange: heterogeneous mechanism................ 107

®ectm of whom uterinOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO 13h

vied-n8 canOOOOOOOOOOOIOOOOOOOOIOOOOOOOOOOOOOOOOOOO0...... 136

FluorOthem migm cenOOOOOOOOOOOO0.0.0.0000...0.00.0... 136

.57. Spectrum of unknown.material as a function of time......... 138

I . DITRWCTION

The stack of reaction kinetics is one method of obtaining inform-
ation about the structure or molecules. Whether the study is concerned
with rates, mechanism, and energetics of chenical reactions in the
classical sense, that is, reactions in which products are different
chemical species from reactante, or with rates, mechanisms, and
energetics of isotope exchange reactions in which products ans chenically
equixalent to reactants is inportant only from the viewpoint of specific
information desired. Both methods of attack yield data ilportaut in
determining the structural nature of reactants and products.

Although some work dealing with isotope exchange in the halogen
fluorides has been reported, there are chest ne classical reaction-
kinetic data for these coupounds.

The present work deals with both isotope exchange kinetics and
reaction kinetics, with, perhaps, the enhasis on the toner. The
system chlorine trifluoride and chlerine , chlorine trifluoride and
chlorine nonofluoride , and chlorine nonoflmide and chlorine have
been studied to determine isotopic chlorine exchange in the gas phase.
In addition, the chemical reaction kinetics of the system chlorine
trinuoride and chlorine inve been studied .

Special equipmnt suitable for studying gaseous reactions or
halogen fluorides has been designed and constructed, including eqmpeent
for the study of isotope exchange in shich a radioactive isotope is
utilized.

II. HISPWIGIL suave: C W FLUORIDES

The know stable halogen fluorides are chlorine nonofluoride ,
chlorine trifluoride , broaine nonofluoride , breaine trinuoride ,
brains pentatluoride , iodine pentatluoride , and iodine heptafluoride .
Excellent general revim of the chemical and physical properties of
these compounds have been given by Thoupson (l), azarpe (2), Gx-eenvood
(3), and Booth and Pinlcston (h,5). Specific information on conductivi-
ties , nagnetic susceptibilities, and vapor pressure studies is given
by finish (6), and on electric noeents by Pruett(7) .

Because the present work is concerned alnost emlusively uith
the chlorine fluorides, attention will be focused upon chlorine nono-
fluoride and chlorine tritium-ids. These compounds, in canon ulth
all of the halogen fluorides, are extreaely reactive, chlorine tri-
i'lucride being one of the nest reactive materials Imam. This fact
necessitates special techniques and equip-out, the details of which
are discussed later, for their stuiy.

Production of the Chlorine Fluorides

There are almost no kinetic data available concerned solely with
the tonation of halogen fluorides, nor is there extensive interaction
on the yields of chlorim nonofluoride or trifluoride under varying
conditions. Ru“ and hie associates (8,9) first me chlorine nono-
flunride by the action of slightly noist tudrogen chloride on fluorine

at rose te-perature; if the gases were dry there was no reaction below
250° c. On the other hand, Damage and Neudorffer (10) reported that
the reaction beteeen fluorine and chlorim in one oto-one ratio to form
chlorine noncfluoride proceeds readily at 220° c . to 2 30° c . A further
method was found by eon-1t: and Schunchor (11), who prepared the
nonofluoride by allowing chlorine and chlorine trifluoride to react at
250° 6.

Chlorine triflucride see first ads by m: and Krug (12) by
passixgalixtm'eofchlorineandexcess fluorine throughatube
heated to 250° c., a process which produced very can mount. of
product. it 470° 0., a tmeo-to-tuc Iixture of chlorine to fluorine
yielded a ratio of one to four of chlorine triflueride to chlorine
accented-id. . fluff and Ireg concluded that the better yields of the
trifluoride were obtained at lower telperatures. However, Seinehart (13)
reportedthattlndirectmienofchlorineandfluerineinacopper
reaction vessel at 200° C. proceeds ineediately to chlorine tri-
auorido. Schlits and Schmohor (11) found thtt the reaction
‘ ' on + r. - cu,
is reversible , and obtained the values shots) in Table I for the
equilibrim constant

P Cl? 0 P F
‘9 " W134
8
TABLE I
EQUILIBRIUH COUNTS roe THE PM“ 0 0mm: WE

__
- _—- A-
‘L

r °c. 180 200 220 250 300 350

¥

_xp at-.xlD‘ 0.069 0.212 0.63 2.93 2h 11:3

 

Isotope Exchange Reactions

The radioactive nuclide F“ has been used for several investi-
gations of isotope exchange between halogen fluorides and other
fluorine-containing mounds. Rogers and late (11;) studied the
exchange between hydrogen fluoride and cone interhalogens. Exchange
intheliqudphaseatroolte-pereturesasfoundtobepractically
instantaneoueinthefollouingsystenet HFandBrF. 3 HandClP33
HP and Brl". ; HP and IF. 3 011‘, and BrF,. These exchanges uere
postulated to occur through ionic equilibria. In the gas phase,
exchangeinthe followingsysteas: HFandClr, ; Brandon;
mandhflaghlandhrt. 3 andfl'andquwasaleoinstantaneousat
noon tuperature . The foraation of intemediate cesplexes vas
postulated to account for these exchanges. Bernstein and Int: (15)
found no exchange between elemental fluorine and halogen fluorides at
temperatures below 100°C . , but neasurable exchange rates above 200° C .
Adana, Bernstein and Kate (16) studied the kinetics of isotope exchange
between elenental film and the interhalogene chlorim triflueride ,
bromine pentafluoride, and iodine heptafluoride. Gas pm» exchange
in the tuportturo range 181° c. to 257° c. was found to occur by
either a heterogeneous neohanisl, or a combination of heterogeneous
and hoeogeneous aechanisu.

Other enhenge reactions, m1. not strictly halogen fluoride
reactions, are pertinent. Dodgen and Libby (17) found no exchange
betseen Indrogen fluoride and fluorine at roo- tenperature , but a
mean-cu. rate at 210’ c. in a copper reaction vessel. Ada-e,

Bernstein and lists (18) studied the kinetics of the hydrogen fluoride-
fluorine systen in nichei apparatus between 19h° c . and 257° c ., and
round that enchenge occm'red by e heterogeneous sechanise. On the
other hand, ohlorim exchenge betleen gassom hydrogen chloride and
chlorine is rapid at rota tupereture but was shots: by Libby and
Johnson (19) to be surrece cetalysed, or heterogeneous. The ludrogen
braids-bromine syst- undergoes repid exchange in the gee phase at
soo- telpereture (20), es does the systee hydrogen iodide-iodine (21),
but the nechenin of ernhenge is not know (21,22).

Sue-err of Properties of the Chlorine Fluorides

Booms In: of tin experimntel procedures as sell as the treat-
Ient of remlts involved in the ark to be described are close]:
cemected with phasicel properties, sees or the properties of the
chlorid- fluorides are listed in ‘rebles II, III end IV. Sane properties

of certain halogens have been listed for later reference.

 

 

 

 

 

mam; II
norm-ms or THE cmm FIDORIDES 1ND 0mm:
W i;— J
c1: cu, c1.
‘ - fl _
Boiling Point, °c. -1oo.8 (h) 11.3 (h) ~3ls.6 (26)
Helting Point, °c. ~15); (1:) ~83 (h) -101.6 (27)
Dipole Holent, D 0.88023) 0.551; (2h) --
Density, g/ni. at 0°C. -- 1.891 (h) 0.003211; (26)
Dielectric Constant at 20%. -- b.28 (1) 1.98 (28)
I I
V r Cle
Configuration -- 9 ..
h
r
planer
o 9- 8 °29'
Bond Length, 1. 1.628 (23) e- 1.698 (25) 1.9814 (29)
. b- 1.598
R
Bond Strength, keel/hole at
. 25°C. 60.6 110.3“m 58 .0

¥

4! References are given in perentheses.
is 'Celculeted free therlecheeioal data in 'rehle III.

an Average bond energy.

TABLE III

son: TWW VALUES ran THE W8 AND THE CW
PIDGDES II THE as PM A! 1 “05PM P11338133 (30)

__.__.—

 

..—

 

35cm

Sylhol All koal » 1e AF local ole * do . Iole
”.11. "V - ’ 3 - ’ - ‘Ybflvifl’fiflfii’lfl " 'i 7' 3 .

F 18 .903 19 .19 111.820 12.30 12 .00 11.69 37 .9173
r, o o o ' o o o twat?

01 28.9112 29 .17 25 .122 39 .1569
C1, 0 O O O 0 0 53 ,291

on .110923 ~11.9h .12 e279 '12 .h83 .12 e507 .1205” 52e062
on. -37.29 -37.10 -27 .96 .2212 41.77 -21.13 68.01.

45 Ar, va1ues at h76.56°x, h97.h6°x, and 518.56% obtained
maim‘cally fro- literature values at 100°!" 500°K,
end .

TABLE IV
Kp vunns’ run m munmnmiwirg. :2 201:,

r in°c. 11p initn.

 

9.5 26.9
20.0 32.1
211.2 35.1:

 

e Reference (h).

M

 

III. dis-mule, nuance, um comrmvc 0913in

Because of the high reactivity of all of the halogen fluoride
We, particularly chlorine trifluoride , a special systems was
constructed. Thissysteluashcusedinahood equipped utheliding
safetHl-“s doors , tin frales of vhich were asbestos covered.
Nichol, lionel,1 and nuorothene were used extensively. One reaction
chanber was constructed of copper, and copper tubing ees used for

several non-permanent connections .
The Gas-Handling System

A schuatic diagram of the apparatus is shown in Figure l, and
a photograph in Figure 2. Pressures of the gases were read from a
Helicoida Bourdon gauge and were considered seem-ate to within one
Iillineter of my. Low pressures were obtained free a McLeod
Gauge nercury neneeeter. Teqsratures were obtained free theme-stars
calibraud agaimt a secondary standard which in turn as calibrated
Caninst a platint- resistance their-meter.a Various traps for measuring
Portions of chlorine trifluoride , chlorine nonofluoride , and chlorine
were included, as well as a system designed for trap-to-trap distilla-
tion, a copper expansion or reaction vessel was constructed and placed

‘1

1 . .
Morel is the trade mark none of the International Nichol Comm for
a high nickel-content alley .

8

Homeroom-ed by inerican Chain and cable Con-pony.
I

A Mueller Bridge was used.

......-

10

.amennaewu H2805

:33 ea>ae> .. O «ensued? new no pegged define... a 3 «£5.33 encannnonqmosa new... sedan->19 no
nmngnenezmd-nue . ® 326» was ex 323» ea: soon an «15» emenoan .3333: .5390 a:
unmade no 3.70 no.“ 2830.530 5 “panache mangooneem flexed: am 323 ewenoam enweoano
330333 rm mason: defiance? Monaco an 3.2.233. gunman one gauze: no.“ 395 H33?
no Hose: .0 Kongo :oaaoeon flexed: am «3233.. mm .23 8.3.0 .395» 93393 300331 3
untagged somog no.“ unguarded mcwgnanem one smashes? one we anemone causaezom ..n shaman

 

 

 

 

 

 

 

 

 

 

 

‘
ee.

m
.8qu on.
U00: 09
.01 o
_ m m H
O n v“. - vNa
e .. o e
en. on. on. on. on. on. on. cu.
H. V“ omseu conga: on.
1 a
Q3 09

m m

 

 

—0

 

n .

oea eea en. on. en. en. eta

Q

 

.mdpwemmmm waflaozmzxmmm use enumnoxe

men do nncomorond .m needed

 

 

 

 

 

12

in a position such that it could. be surrounded with a hot bath for
expert-ants above roon tenperature. A steel cylinder was used for the
storage of radioactive chlorine gas 3 another steel cylinder contained
chlorine trifluoride . A nickel reaction chamber and a counting chamber
for radioactive gases were connected to the gas-handling system;
details of these devices will be given later. The systole was evacuated
by means of a Csnco Hyvac vacuum pump which was protected from halogen
fluoride gas by a large bottle of soda-line , and fro. later by a drying
tower filled with anandreus calcium sulfate. Several take-off con-
sections with flare fittings were lads . The Iain Ianifold line of the
oyster and the individual connections to traps, storage and reaction
chaebers, gauges, and so forth were one-quarter inch outside dial-star
nickel or Honel tubing. All pernanent connections were silver-
soldered, as were the various end-caps used in constructing traps,
reaction chafiers , and counting chamber. Valves were either phosphor-
bronze bellows valves with nickel or nickel alloy bases, or Inconell
diaphragm valves.

The Gas Reaction Climber

l schenatic diagran of the nickel reaction chamber is given in
1"figure 3. The chamber was about 2h on. long and about 11.15 cm. in
die-star, and had an inside volt-e of 311.9 n1. 1 trier-ouster well
was silver soldered into the center of the chasbar, extending back
tbout three-quarters of the total length. The outside of the chanber

‘

l
111ch is the trade nark nane of the International Nickel Co-panv
for a high nichlécontent alloy.

13

 

 

 

 

 

 

To Gauge
B
TO ‘ —._/_.._ ‘ A
Line “2:04/ /C: 71— :7——-— :33
222222 To Variable Voltage Supply

 

: 1.5ure J. Scncmatic diagram of the nickel reaction Ch;flb”“'

.ex, thermometer well; d, nicurone resistance mire, (:), lnccncl
diaphragm valves .

 

 

 

 

 

gas line /” 2 ——*” Coaxial Cable
To Sealer
-A:L¢r Ierlon Ezzsxet
Kselow Flange)
Scale
Aluminum Thyrode . 1 1n. = 2 1n.
Victoreen 1885 ” t
.3
Q h "
Nickel Vessel ~// «

 

 

 

 

 

 

Figure A. Cross-section of the gas-counting chamber.

114

was covered with a thin fiber-glass not over which was wrapped nichroee
resistance wire. This wire wrapping was covered with several layers
of asbestos tape to minimise heat loss to the surroundings. Ends of
the nichroue wire were connected to a variable -voltage or auto-
transforner , so that the taperaturs attained in the chamber , which
was a function of the voltage applied across the wire, was adjustable.
In order to decrease fluctuations in temperature caused by fluctuations
in line voltage, a constant voltage transforI-r as placed between
line voltage and auto-transformer. In this way it was possible to
maintain the reaction chamber temperature at a reasonably constant
value (305°C .) throughout a given experiment, even though the reaction
temperature was considerany higher than room taperature . Llusinus
tubing was coiled about the valve between the hot chamber and the main
line as well as the valve between the hot chamber and the Heliccid gauge .
During experiaents in which the reaction chaimr was heated, tap water
was circulated in the tubing. The reason for this cooling was two-
fald. First, both valves involved depend on a flexible nickel alloy
(Inconel) diaphragl, which is tough, but nonetheless thin, and conse-
quently a critical makness of the systen if allowed to be in contact
With halogen fluorides at high temperatures . Second, the valve
between chasber and gauge was closed during certain experiments, and
“10 temperature of the gas enclosed in the gauge as well as that er
“'0 gas enclosed in the hot aha-her was required for calculation of
I'Btults. It was thus necessary to have, in addition to the volt-es
1“Velvet! , some sharp defining point in the connection such that gas

15

below that point could be said to be at hot chamber temperature , and
gas above that point at another tesperaturo . The valve was ideal for

this juncture.
The Gas-Comting Chamber

a cross-section of the gas-counting chamber is given to scale in
Figuro h. The-ainbcdyotthe‘chawer was prepared to house a
Victoreen 1885 Aluminum Thy-rode. This counting tube is especially
designed to replace thin-walled glass tubes. It has a greater shock
and vibration resistance than glass tubes, and the inertness of
almimn to halogen fluorides sakes the tube valuable for the present
application. In addition, although thin enough to detect 0.16 nev.
beta particles, the aluaimm shell is constructed to resist implosion ,
and therefore is suitable for gas-counting application. Near the top,
the tube is flanged; this flange was sandwiched an. renon" gaskets
which served to males a vacuum-tight seal between chamber and tube when
the specially constructed cap was placed over the tube and bolted in
place . A coaxial cable comocted the counting tube to a Radioactive
Products Incorporated Raychronix 11on Lot sealer.

Because radioactive saterial was being used in the upon-ants,
certain precautions were necessary . Radioactive materials were stored
in a specific area. The nature of the investigations carried out sado
it necessary to produce radioactive chlorine gas tron radioactive
Manson chloride (the details of this procedure are given in a later

F

o —~ .
Teflon is the trade aark nase for E. I. DuPont do honours Coapany's
tetrarluoroethylene polyur.

 

16

section); chlorine gas could then be stored for use as required. It
did not leave the natal handlitg systen until puspod through the
soda-line bottle. Any gas passing through the cysts. plus pulp

escaped by way of a hood. Therefore, the tine of greatest danger of
contamination was during radioactive chlorine production and the subse-
quent disposal of taste naterials. Careful nonitoring of activity

was done with a Nuclear Instrment and Chenioal Corporation Survey
Meter, Model 26101, before, during and after these productions;
residues and wastes were discarded through a University disposal system.
Honitoring was periodically and independently done by a representative
of the University Radioactive Isotopes Conittee.

Absorption Cells

A 10 on. infrared absorption cell suitable for use with halogen
fluoride gases was constructed. This is drawn to scale in Figure 5
and photographed in Figure 7. The body of the cell was nickel;
window were rolled sheet silver chloride; the cell end-plate and
adapter (tor Perkin Elner Model 21) was brass. This cell was used for
expm-nu diseased in Appendix i.

A 10 on. gas absorption cell suitable for investigation of the
ultra-violet absorption spectra: of halogen fluoride naterials is
Shown in Figures 6 and 7. The cell body us nickel; fluorothene-sheet
undows were held in position by brass end-caps. In the lower region
01‘ the ultra-violet spectrun, nun-othene itself absorbs sons light.

The absorption spectrum , balanced against air , of fluorotheno about

l7

 

 

 

 

 

A

r """"" 1

:o o:

: 'I‘" \ t

./ \. Scale
{ .t‘ 1 in. 2 in.
15 a],

i i

: /I

:}~ «4.1

D D E

Figure 5. Infrared absorption cell: A, nickel cylinder; B, phosphor-
bronze bellows valve; C, silver chloride windows; D, brass and plate

machined to fit Perkin Elmer (model number 21) adapter; E, brass and
cap. '

 

 

 

 

 

Actual
Size

   
 

 

. 4
m::as&doi

\i&u

 

 

 

 

7 I “\\\\\\,\\ ‘
‘W

O

F
figure 6. Ultra-violet 10 cm. absorption cell. A. phosphor-bronze
allow:

valve; B, fluorothene window; C, nickel cylinder.

 

"4.2

5

4.: : 1. :,;: E c.

,_l
AVA

a.
_: _ w
, 2::

Z : _ ::..

_ my

‘_ .o

,2};

a

I

.

__~‘i~_
"J— ,
a

3

i=2,

 

 

 

 

19a

aononponosam mo dowvmuowns poH0flbosthn .m onswwm

4 an someoaepen
coma coo: comm

ooom

comm

 

 

a

i____fl________._-

Asawmw nmonMOflAH

:_____:_________

_

_

i

i

 

i

 

 

0.0

m.o

ooa

m.H

oom

m.m

Koueqaosqv

19

four tines as thick as that used in cell windows is shown in Figure 8.
Because of this absorption, a latched pair of cells was made. Ono
evacuated cell was used as a reference, while the other, containing
gas to be investigated, was balanced against the reference cell.
These cells are suitable for use with the Boolean Model DU Spectro-

photoneter .

20

IV. THEORETICAL ASPECTS OF KINETICS AND EXCHANGE REACTIONS
Kinetics

Study of the rates at which reactions occur and the influence of
conditions on these rates is called chemical kinetics (31). In most

cases , the rate of a chemical change is proportional to the concentra- 1?“
tions of reacting substances; consequently, the speed of the process gL
lust decrease as the reactants are being consumed. The curve of re—
action rate versus tine approaches the tire axis asymptotically with '-

very large time values. In practice, because the continuous rate is
normally difficult to ascertain, the reaction rate or speed is determined
at a particular instant; valuable results can be obtained from these
data,

Reactions are divided into classes which are based on the experi-
Isntally (1er 95325 of the reaction, that is, the number of atone
or lolecules whose concentrations deter-inc the speed, or kinetics of
the process. Often, results thus obtained are interpreted in terms of
the nolecularitz of the reaction, or the number of atoms or molecules
“king put in each elenentary step leading to chemical reaction.
Although the order and the molecularity of a reaction are not necessarily
mcritical, the detemination of the noleaalarity usually requires such
”1‘0 intonation than the relatively simle , ldnotically-obtainabls ,
order. Because of this, and because one sin of kinetics is to detemine
“‘0 ole-entary steps of a process , the experimental order is frequently
“bu to be the same as the nolecularity. Fortunately, this is often

the case .

21

Chemical reactions are not always simple; complications may arise

as a result of side reactions, reversible reactions , heterogeneous

(surface catalyzed) processes and other causes. For purposes of defin-

ing classes of reactions, only isolated reactions free from secondary

effects will be considered.

As a representative class , consider a second-order reaction ,

that is, one in which the rate at any instant is directly proportional

to the concentrations of the reactants , or mathematically

1)

where

wfifi' 313

0' .

N

afb

Us

1: (a-x) (b-x)

the rate of reaction

specific reaction rate constant
initial concentration of reactant A
initial concentration of reactant B

the decrease of 1 after tine t - decrease of B
after time t.

It equation (1) is integrated, taldng into consideration that

x-o went-o,andx-xwhont-t,then
2 O ..
2) kt-fiafi 10: [22:] ;a/b

3) let/2‘- -log(E§)+log-2 ; afb

Therefore , if a reaction is second order, a plot of the experimentally
dOtel-minsd log (£5; values versus t should yield a straight line .

The slope of the line affords a means of evaluating It. For the case

‘ r 1'), equation (1) simplifies to

' ‘~." ‘nsx‘uiéis". '0

22

13) % -k(a--x)2

which yields, on integration

5) kt-l (..1‘.)
a 3"!

Here, a plot of (13-57) versus t should result in a straight line for
a second- order reaction .

Classes of zero, first, and third, as well as fractional order
reactions may be treated in a manner entirely analogous to that used
for the second-order case above .

In addition to strict classes of reactions, it is often possible
to deduce mechanisms by postulating a reasonable series of steps leading
ultimately from reactants to products, setting up the differential
equations indicated by these steps, performing the necessary calcu-
lations, and comparing the final rate equation with that determined
experin'nentally. In this process, the intermediate steps are not
Particularly limited; they may involve radicals , ions, molecular com-
Pleaoes , and so forth, even combinations of the above.

Heterogeneous processes are brought about by surface adsorption
Of reactant or reactants. Following adsorption, reaction occurs at the
surface, after which products are desorbed. Of interest in this
°°nnection is the Langmuir isotherm for two adsorbatss ( 36) .

6) 9‘l . bipi . ; 93 . bBPB
+b“+bBPB I+BAP1+EPB

Where 9‘ and 93 . fractions of surface area covered by
l and B at partial pressures P1 and PB

b A and b8 - adsorption coefficients

23

Because b; and b3 are determined empirically, (6) may also be written

91 . b'lcl , 93 _ b'BCB
. _ , y -_ _-
1 + b'ACA '5 b'ECB 1 ... bIACA ... b'BCB

were 01 and CB - concentrations of A and B.
Three cases are of interest

First: two reactants, both weakly adsorbed.
dP I
7) rate “a; ”(9193 -k P1P],

Second: two reactants, 1 weakly and B moderately adsorbed.

a? .
8> w k w k m .k- on
...

u EFBS 2 {Tu-5i FB)2
Third: two reactants, a weakly and B strongly adsorbed.

9) rate--§{-- 1913' kb‘bBP‘PP - k' PA

z —
bSPa ’3
Temperature Dependence and Energ of Activation

In lost cases, the dependence of reaction rate on temperature may

be expressed by the Arrhenius Equation

10) k Ilcxp 6%)

where k - specific reaction rate constant
A - frequency factor
AEa - energy of activation

at

R - molar gas constant - 1.986 cal./nols deg.

T - temperature in degrees K.
The energy of activation for a reaction can be calculated from specific
reaction rate values at two temperatures .

nitropy of Activation

For an elementary reaction, the specific reaction rate constant,

If
k, may be defined as a constant, K , multiplied by a universal frequency

factor (32) [CHI
T

-16 gr
whore KB - Boltzmann constant . 1.3803 x 10 ”We degree

'1‘ - temperature in degrees K.
h - Planck's constant - 6.623 x 10"" erg second
Thus

11) k- xB'r +

K
“'5'"
Although I? is not strictly an equilibrium comtant, it is similar to

one . Therefore, it is possible to define the free energy of activation,
AF". by

+
12) or a-RTan+--RTln(hk
"T‘KB )

and the heat of activation, as * by

13) at!" as” d 1n I: ‘ 111" a ln s... ( )
’ - - -1 m

i
when Kp is K+ in pressure units
1'
Kc is K+ in concentration units
n is the nolecularity (and order) of the reaction

25

then

In) afl’di‘r’ dinik (1%)) -(n-l)RT

37F-

 

+
15) AH an” dlnk -a'r-(n.1)sr

16) air-In“ dlnk -nRT

dT
But fron the Arrhenius equation,

17) 1nk--A3a elnl
T

d ln 1: - Ana
18) 31'3de - A33
T1.
Therefore

19) AH+ - Ans-om

Once AF’ and All" are obtained, then the entropy of activation, AS I...
can be detersined from the relationship

*

20) A5+- AH - M“

Exchange Reactions

Enhange reactions are somewhat different from usual reactions,
because the original concentrations of reactants do not change during
the course of reaction. Often exchange is followed by means of

26

radioactive isotopes, although isotopic mass differences are utilisable
with the aid of a mass spectrograph. In order to derive a quantitative

exchange law, consider the schematic reaction (33).
21) 11 +31? -u* eBX

Where 1 and B represent different atoms or radical greupssxit
represents a radioactive atom of 1.
Define ,in mole/liter concentrations

nus...

31+Bx*-b ,

‘ TV -‘zu's3f.1£1'"_‘?r‘fl

11* - x
31* - y
x + y - z
Neglecting radioactive decay, and am isotope effects, the rate of

increase 3% of if“ is given by

22). %- 3% (J§L)-R§ (Pg!) ntfi Rx +§ a

“hero R - the rate of the reaction between AZ and BK in the
dynamic equilibrium.
Integration of 22) under the conditions, t - oo , x - 3.0 ;
t - o, x - e, that is, A! is initially inactive, yields

 

l
23) 2.3oslost1.,_1.9;g—2 Rt

zoo

Here .3; is seen to be identical with f , the fraction of exchange
xeo

after time t.

27

The derivation holds equally well for the case of molecules con-
taining more than one atom of the species studied, for example, AXn
instead of 1X, but here concentration must be expressed in terms of
equivalents of exchanging atom per liter instead of moles per liter.

An isotope effect, that is, a difference in exchange rate between
isotopes, is noted where the relative mass difference of the isotopes

involved is large (31), 35). For heavier atoms, as the relative mass

difference becomes negligible, the isotope effect becomes negligible.

28

V. THE CIEORINE TRIFIUORIDE-CIEORINE SYST‘D!
Introduction

The combination heterogeneous-homogeneous mechanism found (15) for
the exchange of fluorine between chlorine trifluoride and elemental
fluorine has been mentioned previously. The exchange reaction

2h) 01?, + 013* e—2 01*}; + C1;
(where an asterisk denotes a tagged atom) is similar to the exchange
reaction

25) out,fl + F3 : 611?3 + F:
studied by Adams 21 2..., and consequently was investigated for exchange.
Qualitatively, exchange was found to occur in the gas phase at tempera-
tures above 180°C . However , because the reaction

26) ClFa + 013—9 301?
also occurs above 180° 0., thus clouding the exchange interpretations,

a study of the kinetics of formation of chlorine monofluoride was made.
Materials

Anm'drous chlorine trifluoride , teclmical grade, was obtained from
the Harshaw Chemical Colman. Before use, this material ms purified
by successive condensation-vaporization processes; the gases non-
condensible by an isopropanol-Dry Ice bath were discarded by removal
through the system pump. Each condensate was degassed for several
minutes by leaving the trap open to the pump. Purity of the chlorine

 

trifluoride was determined by means of the ultra-violet spectrum
obtained by use of the cells described in Section III. Three or four
purifications yielded material nearly free from chlorine (Figure 9).
Fluorine (16) and chlorine monofluoride (Section VI) are quantitatively
separated from chlorine trifluoride by the above procedure . Traces

of hydrogen fluoride may have been present, but overall impurities
after trap-to-trap distillation have been estimated to be less than

one mole per cent (6,7).
Chlorine“ was selected as the tracer. The disturbingly long

half-life of four hundred thousand years is partially compensated, from
a safety point of view, by the weakness of the negative beta emission
(0.72 mm). The c1"3 was obtained from on: Ridge National Laboratory
in the form of aqueous hydrogen chloride which contained four micro-
curies of activity per milliliter. Tagged elemental chlorine was made
according to the reaction (37).

27) mo, + 21m + gem—wow. + ago + 01.
The system used for chlorine production is shown in Figure 10. For one
batch of chlorine, the following were placed in the reaction flask
and heated to about 80° c.: 17.55 grams sodium chloride, 13.17 grams
manganese dioxide pretreated tdth concentrated nitric acid to remove
12.375 ml. distilled water, 12.375 ml. sulfuric
The gas

manganous carbonate,
acid an 0.825 ml. of the tagged hydrogen chloride solution.

produced was washed with a saturated solution of copper sulfate to

remove hydrogen chloride, then dried with concentrated sulfuric acid

and anhydrous calcium sulfate. The sodiu! chloride was Hallinckrodt

Q)

.asnpooam ouwnosamwuu ocanoano .0 madman

« as someoaoooz

 

 

cows ooos comm .. doom oo comm ooom comm ooom oosm
t..." .. olfilrul _._4._1. _4_a_

. u .w -n 1.9 .

I
u .‘vnu
.Avnl U- 7
i t ( I
7 o 7/ L

U
0

modes o>se attested

moss» ozo bowestod

.85 OM HI... whflmwwhm . I.

 

 

0.0

m.o

O.H

m.H

O.N

m.m

Koueqdosqv

31

.toooaofiofi one Honda methadone one: 833 blood eoflooot .e «332

messes: commasm seduce eopmuspmm .& modeup hwommm am «cappon wcwsmmz owes oflhsmasm an meopmhm
Hopes op Hm>oaon beckon esauoano mo soapMmcovcoo mom asap ao moaahofihn :pwz voddfim mops» mswhhv am
meoamhm Hopes op wcfiumoa mswppwm vouonsp a< usofiposuosn onwhoazo you Eugene nomad .OH enamfim

 

 

 

 

 

 

 

 

 

 

 

 

 

32

Analytical Reagent; the manganese dioxide was Central Scientific
Canpany technical grade; the sulfuric acid was DuPont C.P. of specific
gravity 1.81;; the nitric acid was DuPont C.P.; the copper sulfate was
Baker C .P. pentahydrate; and the anhydrous calcium sulfate was
W. 1. Hammond Drierite. After production, the tagged chlorine was
purified by successive condensation-dogassing-vaporization treatments,
after which an ultra-violet spectrum of the gas was taken (Figure 11) .
The activity at various pressures was determined in the gas counting
vessel (Figure 12). The gas was stored in a steel cylinder.
Non-radioactive chlorine of technical grade was obtained from the
Ohio Chemical and Surgical Comparw and was used where applicable after
being dried by mono calcium sulfate and purified by the conden-

sation procedure.
Exchange Procedure

Study of the exchange reaction between chlorine and chlorine tri-
fluoride Ins carried out in the nickel system described in Section III.
Equal amounts (as determined by gas pressures) of chlorine and chlorine
trifluorid: were mixed under the varying conditions of the particular
experiments. Each constituent ms kept out of contact with the other
until actual mixing. For example , chlorine was expanded into the
pro-evacuated reaction'vessel to a pressure of about three hundred
millimeters of mercury, then cordensed into the chlorine trap by liquid
nitrogen an! the valve closed. Similarly, chlorine trifluoride was
1: i

A correction was applied where necessary for chlorine trifluoride
dimeriaation (h) .

 

33

.Eduuoomm enamoano o>fipomowemm .HH masmfim

 

CH npwmoao>m3
00m 0004 Comm Comm am 1 comm ooom 00mm ooom oonw
_ 7% . _ _ a d. .. .4 _ _ _ _ _ _ 74 _ _ a
n 0000.
0
00 c
In. 9. -l.
r4 ‘a
z
a
l J
o .EE 0m_w oasmmomm
o
e 9 \
_%__T»L_________F_L.

 

 

 

0.0

m.o

O.H

m.H

O.N

m.~

Aaueqdosqv

 

 

200'-

 

l l
R 8

H H

'oee/squnoo u'; £413.;qu

..78

250

200

SSUFG 1U

 

mm.

‘we Chlorine a

..
.—

VaFlCKS pressures.

t

v.4

35

measured and condensed into the chlorine trifluoride trap and the valve
closed. The cold baths were then rasoved from both traps , and the
traps warmed to room temperature, after which both valves were opened
simultaneously and the gases allowed to mix during ezqaansion.

Reactants were quenched by condensing the mixture into the first
trap of the distillation system with a liquid nitrogen bath and were
subsequently separated by distillation. The distillation process
consisted of placing a liquid nitrogen bath around trap number two
(Figure 1), replacing the liquid nitrogen bath around trap number one
idth an isopropanol-Dry Ice bath, and opening the valve between trap
one and trap two for five minutes. This allowed the more volatile
chlorine to be separated from the chlorine trifluoride. Then the valve
was closed and the procedure repeated from trap two to trap three for
three minutes. Trap one was immersed in a cold bath even when not con-
cerned directly with the distillation to insure a low pressure inside
the trap, The final chlorine fraction in trap three as warmed,
expanded into the gas-counting chamber at a pressure shown by the
Helicoid gauge, and counted. 1 ample of the gas was taken for spectral
analysis, (s as Figure 13 for a typical spectra). After counting, this
gas fraction 13s discarded by pumping through the soda-lime bottle .
The chlorine trifluoride fraction remaining in traps one and two was
Purified several times by the condensation-degassing method, then
Olpanded into the counting chamber and counted at a known pressure.

1 liuple of this gas fraction also was taken for spectral analysis,

('00 Figure 1’: for a typical spectrufl.

36

oomq

ooo¢

.cowpmaaflpmflo nmpmm COflpomnm ocwnoano mo.adhpooam .ma onswflm

comm

000m

do as fimcoaoaoz
8mm

0

ooqm

000m 00mm

ooom

\DOdN

 

 

fl

0

’4

.88 on

r4

U:

onsmmonm

'4

'1

\a

a _ _ _

404

\x

3

C

C

_ _

0 D
‘

0'—

0.0

s m.o

O.H

m.H

V CON

 

 

m.m

floueqaosqv

)7

.GOflpmmafipmfio nmpmm nowpomnm mUHhosHMfinu sawhoano mo Enhpomam .4H mudmfim

s so nomaoaosoz

 

 

 

 

 

 

 

 

 

 

cows oooo comm comm .ooom comm, ooom comm ooom ooow _« o
p, ,p _; _ _ ._ _ _ _ _ fl _ _ _ _ _ 0.0
Q ( CITM 0 )
l. > ,
C C
.1. moo
.. o,H
.15 Oman magmmmnm Il-vmna
.1 (ohm
_ _ _ _ _ _ _ _ _ _ _ _nnnur. .

 

Kousqaosqv

38

For exchange experinents at temperatures up to 170° 0., the copper
reaction vessel was used inersed in an .lroclor"i bath, the temperature

of which was neasured with a themoneter. Experinents at higher
tewperatures were done in the nickel reaction vessel heated by nichrone

resistance wire.

Exchange Results

No exchange was founi after one-half hour contact ties between a

mixture of equal parts of the immiscible liquid chlorine and liquid

chlorine trifluoride . The reactants were condensed with liquid nitrogen

into a £111th trap the valve of which was then closed, and they
were nintained as liquids by replacing the. liquid nitrogen bath vdth

an isopropanol-Dry Ice bath. The trap, which had an outside diameter

of about six nillineters and an inside dianeter of about three silli-

neters, was somewhat liter; it as flexed to agitate the liquids inside.

Trap length was about fifteen csntiseters. The liquids were qualitatively

innincible since a line of denarcation appeared roughly at the center
of the liquid column in the trap.
After a contact tins of two hours, exchange between a nixture of
equal parts of gaseous chlorine and gaseous chlorine trifluoride did
M take place in the copper reaction chamber at te-peratures up to
1650 C. The pressure in the reaction vessel at each temperature was calcu-

l‘m free the seamed gas pressure in the reaction vessel at recs

Writers .
Tr - -

HM Chenical Coepany's molar-121:8, a chlorinated biphenyl.

 

39

Qualitatively, chlorine exchanged between chlorine trifluoride and
elenental chlorine after a reaction tine of fifteen to thirty minutes
under a pressure of six haired millimeters of mercury and a temperature
of 255° c. Quantitative data were not obtainable because of the

couplicatim reaction
26) 011‘. e 013—9301?

which was found to occur in the tenperature range necessary for positive
exchange results.

Procedure for the Study of the Kinetics of Formation
of Chlorine Henofluoride

Initial counts ef reactants were neasured in the gasohandling
system and aired in the copper vessel. This vessel served as an
expansion chenber throughout the experisents. Chlorine trifluoride and
untagged chlorim were purified according to the neth already described.
After sizing, the reactants were expanded into the pro-evacuated nickel
reaction chalber which was kept at the desired taperature. The expan-
sion process consisted of complete opening of the entrance valve to
the nichl ember at tine sore , followed inediately by closing of the
valve. As soon as the valve was closed, reaction chamber pressure was
recorded. This entire process required approxiaately ten to fifteen
seconds; the pressure recorded was assuned to be the equilibriun initial
pressure of reactants at tine sero. Subsequently, pressure was recorded
as a functien ef tine.

110

Kinetics Results

Recerded pressure data were first corrected for gauge deviations by
some of a calibration curve (Figure 15) for the gauge involved. Since
the pressure gauge was at ree- tenperature were no reaction occurs
and the reaction chaaber at a such higher temperature , a second correction
mappliedferthe gasvelmenovingfmsthe hotchanber into the
gauge. Because the change in pressure was initially large, there was a
large positive pressure on the gas in the gauge; it as asstned that
for the first put of the reaction no back-diffusion of unreacted gases
fra the gauge to the hot chainer occm'rod. In addition, it was assuned
thatanefthsgasdisplacedintothegauge chasberwaschlorinenene-
fluoride, or conversely, that none of the original reactants were lost.
This is reasonable since in the begiming, displace-ant was snall; by
the tine the correction becaee relatively large the reaction had pre-
oeeded sens distance, and hence the displaced gas was largely the product,
chlorine nonefluoride. Consider the reaction

26) c1, e on, ——>301r

a pressure increase will be caused by the fersatien of chlorine none-
fluoride . If the entire syste- were aaintained at constant temperature ,
then the pressure read would be the pressure of the reactants plus
products. Gas inthe gauge atroatelperature willnet react. Gas in
the reactien vessel at a higher tenperatxn‘e will react producing an
increase in presets-e; in order to cause an increase in observed gauge
pressure some of the gas must nove from reaction. chamber to gauge.

Al

.9“ am. oMooHHon. now ego nowmmhniin Tom .3 E

l

.5 GM 93893 donned...

 

 

00m 8“. 03 can . 00¢ P QR CON 8H
_ p _ _ _ _ _ _ _ u A q q .
omssm o
_ a _ _ r a . _ T . _ _ p

I. OON

loom

- 184

L005

 

 

'unn U1; ssnsssdd efinsfi prongs};

142

The effective gauge volune relative to the reaction chaaber volume is

given by
28) V'g - Vg ( {:8- )
where V'g - effective gauge wine at telperature of reaction

vessel
Yg - actual gauge volule - 19.6 ml.

Tr - tolpsrature of the reaction vessel in degrees
Kelvin

Tg - tenperature of the gauge in degrees Kelvin
The total effective value of the syste- is
I 73' e 'R
where 'R - volt-e of the reaction chamber - 311.9 :1. Gas will be
distributed equivalently throughout the entire volume . The fractional
effective when of the gauge is

H37

3 t 3

Therefore, the .....e of gas (in terns of pressure) being displaced
into the gauge is N ’

(Pt - Po? ( h )
flherePt -totalpressuroattinet
Po - initial total pressure
or the change in pressure tiles the fractional effective voluae of the
me. Consequently, the corrected pressure, that is, the pressure
thatweuldappearintheroactieacmerifnegaswerelcstis

LB

29) Pc IPt + (Pt -Po)( %R)

where Pc - corrected total pressure at tine t.

This correction is initially «all , for onwple under conditions of
Po oboe-... Tr -2oo° c., 1'; -30° c. andPt duo-n

19.6 ( [‘7 )
Po - 1110 e (1110 - 1100) __ - 1110.90

19.6 ( 1‘7 ) + 311.9

 

Prusures of chlorine, chlorine trifluoride and chlorine nono-
fluoride were calculated from the corrected pressure values. Consider
a reactant sisters of equal anounts of chlorine and chlorine trifluoride

at an initial pressure, Po, of 1300 n. Then
p(01r,), - 14:21,), - 21°, - 200 ..

P‘Cll'). . 0
it tine t with a total pressure Pg
30) P(cir,), - N01,), - £3 - (Pc ~P,) . £3 + p, - Pc - 25’s - P.

31) Hair), - 30¢ - Po)

T $

for a 1:1 nix of reactants, and

1.. $3,: "on; I» one? on

01'

log :gg’t)‘ vs.tile; P (ClgpP (0133):,

M

for cases where initial pressures were not equal indicate the reaction
proceeds according to a second order rate law. The data deviate from
straight line relationships as reaction tine grows large . For the case
of equal proportions of the reactants the deviation is always such that
the ratio P(9_1!_),/P(c1r,). is too large. This can be explained by the
back diffusion3of unreacted gas fro. the cold gauge. Toward the latter
part of the reaction, the expansion positive pressure decreases because
the rate of reaction decreases, hence sons back diffusion should occur.
This tends to increase the relative aneunt of reactants in the reaction
chawer. However, the ratio P(ClP),/P(Cll‘.), was obtained wing P(ClF,).
calculated asstning no back dif-fa—sion, and therefore, since P(Cl!',).is
actually larger than that plotted, then the ratio magi/Hang. is
actually suller than that plotted. The case of the gen-equal starting
anownts of reactants can be explained by entirely analogous reasoning.

Plots of the oxperinental data treated as discussed above are
given in Figures 16 through 36. The lines drawn to calculate slopes
of the curves are reproduced as precisely as possible . Values of the
specific reaction rate constant, It, were calculated in the following
nannor. For a 1:1 nixture of reactants

32) k - 2.1.32.2
where c - [6115310, the initial concentration of chlorine

trifluoride
or c - [012],” the initial concentration of cllorine.

For a non-1:1 mixture

33) k - 2,22 310%

a - b
When 3 " {912103 [01310 > [cuslo and b " {Cl-F310

or a - (01%),; [c113], > (01,]o and b - {Ola-lo

Ls

.oeonfl um language,“ ovflgdmga oawfiodau dd 3

hunches on than

 

0H 3. NH OH m o i~ o
_ _ . _ ~11 _ .w _ q _ o
0
_I O O Ii N
0
u: l
1 l d
if. , J 0
_ _ L — _ _ _ _ _ _

 

 

   

 

 

Cgto d E/dTO d

P ClF3/F 612

100 A, A

 

60-

hOr- G.

N
O
1

...:
O
.l

I

 

2., J l 1

 

 

      

"f

 

 

     

10 fi 15 20 25 30
Time in minutes

Figure 17. Chlorine monofluoride formation at ZL'°

 

I
35

V.

L"!

C)

L6

P 012/? ClF3

30

20

10

 

 

 

. I A I I I I Li I I I I L;

‘ij

1

 

,1-..ul.__lm. 1

a

 

 

 

I
2 A 6* 8 " 10 12
Time in minutes ‘

Figure 18. Chlorine monofluoride formation at 240°C.

14

A?

P c12/P ClF3

#8

 

6 ~ ’47 1 1 I I I 1 I I
r- -1
III- .-I
I— Q "
40— .4
.. O .1

1
J

20_- -«

 

 

 

 

10 -
8 ...—I
a ._

J L I I I l I I I
2 2 a, - 6 8 “'I0

Time in minutes

Figure 19. Chlorine monofluoride formation at 2hO°C..

60 _

LO

20

P ClF3/P 012

...s
O

 

 

 

 

 

Time in minutes

Figure 20. Chlorine monofluoride formation at 2hO°C.

I I I I I I I I I I
I— ...-I
I'— —-I
L. ..
P- --I
0
r- --I
0
I'. —4
—-II
.—I
I he I I ' I I I I I I
, 2 I. 6 8 10.

1+9

5O

.ooOiNN an nowpwflfiom ooflhgamonofl mfiodau .HN ohmeh

moaned: mun o5

 

 

 

o
a _ _ _ _ _ A

 

~-

 

 

51

.o.oe~ he eenoeauem eeeheaaueaea.ueeheazu VNN themed

no use?” dun 06.2.

 

0H NH OH m o w O
a _ _ _I _ q q q «I qI
Q
Q
I 0 I
O
I 0 ll
Tl IL
I J
a — _ _ a _ I_ _ _

 

 

 

Cato d S/JIO d

P ClF3/ P 012

 

 

 

 

 

 

 

30 . I I I I I‘ r I I T I'“”"‘|‘ 7
I" -I
20 r- ._
I- .i
C)
10 - C) ._
q
r'm _._
2 —- -»
1 I | I I I I I i I I I
o L I a 10 12 14

Time in minutes

Fiés'ure 23. Chlorine monofluoride formation at 220°C.

52

 

 

.. \0

WI

-- «I

 

m \0 .-3 (\I H

are d/ggro a

f‘“" vv -
¢ ‘--~a -.a'

“Q.

I

run.
#8

P 0115/? 012

to

20

....e
O

(1‘

 

 

 

I" III I I I I I I
I— ....
L- _
P —
II- ...-I
- -I
.1
_ ...I
L I I I I I I
O” **i '1. 6 e lo

 

Time in minutes
Figure 25. Chlorine monofluoride formation at 220°C.

5h

OH

.nom moanedmmomofi.ouwnoano .wm made

mopscwa cw ofifla

[T4

0

 

 

4
C n A

L

 

 

OH

1

*f‘
t'. t.‘

I

,_./c

IT-En
LI

..fi/
.conNN gm nowmeMom onwhonamocofi mCHLOMno .bu ondMH

mega. . 5 25.9
o d N

 

m
A n _ _ _ i _ _

 

 

 

 

OH

P 0119/? c12

 

éotl IIT I I'WI I I

#0

1

he 5
IrII

I

I

 

IILI

I

LIJI

I

I

 

 

2 I I I I I I %
IF ~ + E T

Time in minutes
Figure 28. Chlorine monofluoride formation at 220‘C.

it

57

 

 

lO

 

 

 

are d/€3IO d

n minutes

'\

'r'I

lune

58

““fiofl
‘A‘d u e

ation at

4.:

for”;

:-1 u _'

\ u,qr\o‘
v _;~‘I-.~/_L

’4‘.
A.

29. Chlori

P ClF3/P C12

 

 

60
__ I I I I I I I I .1
I— .4
1+0 r— .—
20 -— --+
10"' “
8*-' .—
b— —-I
6— 0”,,” —-I
a ....
[- -I
2 I I I I I I
U I f r I o ‘ 4;

 

 

Time in minutes

Figure 30. Chlorine monofluoride formation at 220°C.

59

60

.neONN um SOHpMELom weaponamouofi onwaoano .Hm madman

moaneda a“ mEHH

d N

 

I+

 

~«o

-uo

.-q

_ _ _ _

 

 

 

 

0H

are d/Cdto d

 

 

.I-Jrl )

 

 

0.6-

4

O
cno a E/JIO d

 

61

\-

O

3.- _-
{)“V'C‘. I."".‘ ,
-‘L-‘U‘VOC .1

1‘
.L

oriee

‘1

-.dA-n"; 3. -..-

Yr-1‘.-*5r7

Ere

"F‘ «17-:
U‘fiUAJ—

62

 

.ueomH am noprfihom mowuomdwonon muwhoflno .mn o

moheeee he «see
0: om om
_ _ _ q _

)

named

 

 

 

feta d s/dIo a

63

.903 um sewage.“ 328688. «533”. 1a themed

newsman cw Mafia

 

 

0m 04 om 0N

_ . d _ _ _
T I.
i

Aw
Aw

TI
i.
1

Ib — _ b p _ — _

 

1

d
e
O

@.o

 

 

C£1130 dE/JIO d

61+

 

0m

.oeomH an competes.“ oownooawooofi menwaodau .mm ogmfim

mouscg 5” can.

04 on 0N 0H
_ a _ _ . _ .

‘\

\\

 

 

0.0

No.0

"I
0

0.0

Eats d E/an a

65

 

.meomM m. Gowfinflom othQuHMOQa mqmuogu .wn mnermflm

mood—HHS 5." 03m.
3 on ON 3 0
fl, . ~I q dI _ _ . q! I 0.0

 

 

 

sits a e/an a

66

Concentration values were calculated from pressure values by use of

the ideal 3618 law.

3b) PV nRT

where P - pressure in atmospheres
V =- volune in liters
n - number of moles of gas
R a molar gas constant - .08205 fitiégme
T - temperature in degrees Kelvin.
The results for three different temperatures are summarized in
Tables V, VI and VII.
lemming an Arrhenius equation relationship between specific

reaction rate constants

10) k- .lexpé-efigaa
17) lnk- - %—‘— + 1111

_ ~AE£ 1
35) 108k m *‘ mil-1031

Then

If log k ‘Vs. %. 1: plotted, then

- sta .
m ’1°"°

36) AEa - - slope 2.3033
Average specific reaction rate constants were plotted vs.% in

Figure 3?. From the slope of the experimental curve, AEa was calcu-
lated to be 21.8 kcaL/uole.

‘
“W

I

[I

_ ...—A—

____v

...A‘__‘_._-_

TABLEV

A_‘

+

KDIE‘I'ICS cr cmenme noncrwoeme rename AT 2ho° c.

_‘ -..—

A‘

67

 

Figure P03: .a) o “2 f). o mole/l . milE/l. secf']: (:10’) l .nole'lisec . " ‘
igeoaziiegahi- ._ In
16 217 .0 217 .0 6.78 O 2 .262 0 .3320
17 285.3 1b2.7 - h.h6 0.553 0.2853
18 1h2.7 285.3 - h.h6 0.617 0.3190
19 85.8 3h3.2 - 8.0h 1.681 O.h818
20 3hS.6 86.h - 8.10 1.32h 0.3761
21 111.0 111.0 3.h7 0 3.125 0.9015
22 160.5 160.5 5.02 0 2.679 0.53h0
-- 57.5 57.5 1.80 o b.239 2.379‘

k average O.h61

‘_- A A A ‘— ‘—
.—

V v * mv—v— " "i ‘—

+ See.ippendix II for original data
-* Discarded on the basis of statistical deviation from the noan.

The equilibriun constant for the reaction
01?; '0 613 . 36“
at 2h090. was calculated fron thernochenical values (30) to be

my):

‘ e
KP I P(Cl?3) P(013) " 8.7 X 10 8".

68

TABLE VI
. . a
MISS CF Cm HONGFLUORIDE FORMATION AT 2200 C.

___.‘___A ____.
*7 V 7—i— v — w w
‘_- —-.._- __‘__. ...- u A ‘_ A; __ _
‘— — —— v w. w ' _r__

 

Figure 903115). P(01.). c a-b 539' R
an. an. lag-3g. :30 . sec. (310’) l.nolo’1sec.'1

23 mm 86.0 - 8.39~ 0.5620 0.1510 '
2h 3th.8 86.2 - 8.II1 o.606II 0.1661
25 3113.2 85.8 - 8.375 o.II9SS 0.13611
26 3115.6 86.II _ - 8.1135 0.7826 0.2138
27 3110.0 85.0 - 8.295 0.6578 0.1827
28 303 .8 77 .2 - 7 .532 0.7112 0.2176
29 3h8.0 87.0 - 8.1I85 0.1228 0.3336
30 310.2 85.8 - 8.375 o.h682 0.1288
31 3&8.0 87.0 - 8.1185 0.6522 0.1772
8"]: average 0.190

_ _ _
“- .— - __‘
w fl w _ ‘—

+3ee appenanurer «13111.1 data .
The equilibriun constant for the. reaction
011', + Cl, 7 3le
at 220°C . Ina calculated fron thermochemical values ( 30) to be

2(0111’

6
Kp " P(ClF,) Hal.) '4 8'3 " 1° “"

69

TABLE 711
+
xnmxcs a 011mm: 11017011103108 momma 11' 180° 0.

_A A.“ _-__- _— #A— A _.__ ___._‘ - A
~— “w —— —_

A‘ A —‘ _“_. __._

T— W w vw
j...

p P 011' ) P031 I “b 31 k
igure (-3 0 III2 0 3012/1. Izhe- ”0.092110” 1J°l°-1°'° '4
(310:) (1103)

——-———A _____ ‘- __‘_‘ A——_‘ A

32 208.0 208.0 ‘ 7.36 0.18870 0.02562

0
33 213.5 213.5 7.55 0 0.18055 0.02390
34 215.0 215.0 7.60 0 0.1990? 0.02620
0
0

 

0 .22222 0 .03196
0 5201.08 0 .02866

35 196.5 196.5 6.95
36 201.5 201.5 7.12

1: average 0 .0273

L_‘ h .... - ... “-

w * vv ~—

1- See Appendix II for original data

The equilibriun constant for the reaction
611", + C1, - 3011"
at 180°C. nae calculated frol- thernochenical values (30) to be

3

k, l./mole sec. 1:10‘8

70

 

 

 

 

(‘3 I I I r
I- -—I
1.0 - -I
P‘ -I
‘20 ._ _
'I
10 _ ...
I- q
8 '- u-
I- cenI
. 6 .- ..
I- .0
h h- .—
- -I
2 _l I I J .
1.90 2.00 2.1-3 3 2.20 2.30
(:7 / ‘5' l/T, degree” It 10 '

Figure 37. Arrhenius plot for chlorine monofluoride formation.

71

Using the equations given in Section IV, the entropy of activation
for the fornation of chlorine nonofluoride was calculated.

+
12) AF - -RTln ( fi-I - - (1.986) (h93) (2.303) 108

(1.901 x 10=)(8.622. :10"?
(1.3803 1513'“) (1:93)

M ,'-I

a" - 2h,213 cal./nole

+
19) AH - AEa - Inn 21829 - 2(1.986)(II93)
II
AH - 19.871 cal./nolo

e + t
20) A3 - AH - A! I 12811 - 23212 - ~8.81 0.11.
I .

t
For the calculation, the standard state for as was taken as one nolo

per cubic continoter; consequently, the units of I: were cubic centi-
neters per nele second. For a binoleculer reaction between polyatenic
nolocules 48+, with one nelo per cubic centineter taken as the standard
state, is expected to be negative, because of the decreased probability
of activated couple: fornetion associated with the necessary changing

of rotati6nal degrees of freedon into vibrational degrees of frooden.

Discussion

There were three nain sources of error in this experiment, nanoly:~

1. Uncertainty in the initial tine andpreosure (Po) readings
on expansion of gas into hot chamber.

2. Assaptions necessary in correcting for unreactod gas in the
pressure gauge chamber.

3. Possible errors in neasuring tonporaturo and pressure.

72

The overall error was estimated to be between five and ten per cent.
The activation energy is probany accurate to 3 1 Real , and the
activation entropy to 2 0.5 o.u. -

The bond energ+ of chlorim trifluoride may be calculated from
heat of fornation data (Table 111, Section II) .

 

37) 011', - 3/2 P, + 1/2 01. on, - 37.3 hon/nae

38) 1/2 01, - 01 AH: - 28.9 heal/nole

39) 3/2 1", - 37 on, - 56.7 local/hole

1.0) 01!, - 37 e 01 on - 122.9 ted/non.
hence

D - 122.9 /3 - 111.0 Ell/301°
Assuning D is a fair approximation to the actual A8 of one chlorine-
fluorine bond, the heat of foraation of 01!. nay be estimated.
In) 01!, -cn. of AH 2’0 “0.0 Izod/non

7h“ 41114013.) 2: AHf(cn',) " Aflfa') +1.1.0
AHf(ClF2) -37.3-18.9 0 111.0 s 45.2 local/sole

II

An upper linit for the chlorine-fluorine bond energy could be taken as
the bots! energy in chlorine nonofluoride

 

M) 011' - 1/2 01, + 1/2 1‘, auf- 11.9 kcal/nole
38) 1/2 01. - 01 AI-If- 28.9 Whole
1.3) 1/2 I. - r AHf- 18.9 kcal/nolo
MI) 011' - 01 or All 359.7 ton/.21.

A v ues used in this discussion were those at 298.160 K.
Table III shows that this is a good approxination.

73

In this case
AHf(ClFa) - ARI-(0113) - AIR-(F) + 59.7 - 3.5 kcal/Ieole

Consider possible steps leading to a second-order rate law for the
foraation of chlorine nonofluoride . A free ~radica‘l. mechanism such as

15) 011', + c1, .51..) cu + 01 + 01172
1.6) 01 .0115 1L9 20]!

yields the rate law
1.7) - d 011') - 1140115) (01,)

which satisfies the second-order requirement. However, this rate process
would require two radicals to react with each other in preference to
reaction 14th the higher population of chlorine or chlorine trifluoride ,
which seems unlikely. In addition, the emerinsntal activation energy
should be at least equal to the enthalpy change in reaction I45). But
for I15)
AH - -48,(c1r.)- Angst.) + Autumn + Angel) e hermit.)
AH - 37.3 + 0 - 11.9 + 28.9 - 15.2
AB - 39.1 keel/mole
which is substantially larger than the 21.8 kcal/nole activation energy.
If the upper 11w; value for Anger.) is used, the enthalpy change
in MI) is 37.3 . 0 - 11.9 + 28.9 I 3.5? 57.8 teal/mole, which is higher
than the value obtained previously. Finally, suppose the bond energy
of the first chlorine-fluorine rupture in chlorine trifluoride is

7h

arbitrarily taken about equal to 22 local/mole ( AEa) . The total
energy of bonding in chlorine trifluoride is about 123 kcal/uolc , fron
IIO) . This indicates that each renaining bond would have an energy of
about (123-2a/2 - 50.5 kcal/nole or, by IIII) within about 9 local/hole of
the energy of the bond in the nonofluoride,‘ which seens sonowhat unlikely.
It is no doubt possible to approximate both exporiaental activation
energy and order by a free -radical chain mechanis- assigning suitable
steps and stepme activation energies . Hanover , such approxinations
night he considered rather arbitrary, because there is not enough
infornation about the systu to allow selection of stepwise activation
energies, for example , which could be verified for self-consistency
with other vork.

An alternative nchanisn is

I18) 01!, + Cl; —KL> 01? a» Cl; e F;

I19) r, +01a —K—‘> 201:
which again yields the proper rate law. The enthalpy change in 1&8) is

AH - Amen) + Anf(c1,) + Auto.) - A3601.) - 218140115)

Ali-I -11.9 + 0 +0 .0 +37.3-25.IIIIca1/mo1e
The energy requirement is thus reasonably close to that found experi-
Ilentally . However , chlorine trifluoride is known to disproportionate
(rabi- I) in the tenperature range studied. It therefore see-s that
no bimolecular collision between chlorine and chlorine trifluoride
muld be necessary to obtain the products indicated by stop he) .3

A third alternative is to postulate the existence of a complex

intermediate. For example

75

50) 011', e 01, ,_KJ._)C1F,~C13
K3
51) 0173-013 —e 30117

This nechanisn would yield a second-order rate law provided the rate
determining step is aseumd to be 50); a second—order rate law is also
found if ‘50) is written as a reversible reaction, thus implying a tram--

sitionQ-stato-complox, which may be preferable. This process is certainly
energetically possible. Supporting evidence can be obtained from the I
large negative value for the entropy of activation. For a given case

the more negative the value of ASI, the smaller the steric factor
hindering the formation of the activated complex. For the present case

it is possible to postulate a couple: which night be expected to form

with little steric hindrance. Chlorine nay Join the chlorine tri-
fluoride nolecule at either wing of the planar tee , and then break

apart to yield chlorine nonofluoride es schematically show below.

I I I
52) c1-r + 01;:01-1 __501—--r\ ...)3014
‘ I I I )01 : ,01
F 01 In P ,’
\ 01 \01

Fron the planar tee structure for chlorine trifluoride

FI/ci1\ F1
1'2
the r, — r, distance is 2.280 1°. Since the 01 - 01 distance is 1.981. 1°
in the Cl, molecule , the complex pictured in equation 118) is plausible.
A number of possible mechanisms other than second order were tested

with the experimental data, tdthout finding a rate law which adhered

76

to the data. Some mechanisms tested were

A. A first order rate law

B . ' mechanism rate law*
.511
011'; T 01F 4’ F3 Pclrua PC]!
- -"'"-"" '
'1‘ 21”total K P012 * K
r, e 01, 4—; 2011' at
i
C. mechanism rate law
013 .121, 201
x
01 e 011', _'_> 011', + 01! or 7a
total I (P01! )

 

‘ I
011:a + 013 J.» 2011r + 01 dt (Pt m)
0

H061 +Cl—Ki-)613+ M

 

 

(H a wall)
it
D. mechanism rate law
Kl
01F: "—9 CH3 ‘0' F
‘ x
r + 013 —’—> 011' e 01 7113mm ,4
K: d K (Pena) - K'
01 +ClF, ———3 01? + 011'; P _
PC”; ( totInIV2

01!, +013 i920]! +01
M +01 +01 _K_.;)'012 +M

 

-I

dpggtal values obtained graphically from pressure and time data.

mechanism
01: fig. 201
Cl +»01F3 ——Eg> 01!, +-ClF
011? +011?a 31> 01 +013,
011-. + 013 .199 2011' + 01
01 + 2011' .51) 01F; + 01,3

01 +01 33—) 01,

77

rate law

 

 

' PC . P
3! . x 401
dPtotal P011r
T
and
(Pony P01
. . '
dPtotal K 5"!
dt 01?

The first expression applying in
the early stages of reaction,
the second near the end of

reaction.

78

VI. THE CHLORINE TRIFLUORIDE 1ND CEEORINE MONOFLUORIDE SYSTEM
Introduction

Only qualitative data were obtained in the study of chlorine
exchange in the chlorine trifluoride-chlorine system because the reaction
to give chlorine monofluoride interfered. However, this circumstance
was fortuitous in that it indicated the feasibility of production of
chlorine monofluoride for experhhentation purposes . Moreover , tagged
chlorine monotluoride production required only one additional operation
beyond those needed for the chlorinei-chlorine trifluoride exchange 3
namely, the application of the formation reaction studied in the preced-
ing section using tagged chlorine . Furthermore , an exchange study of
the chlorine monofluoride-chlorine trifluoride system was expected to

yield quantitative data since no side reaction was predicted.
Materials

All materials except chlorine monofluoride were produced in the
manner described in Section V. Chlorine monofluoride was produced
according to the reaction

53) 01.?3 + 01: ——> 301’17
in the nickel reaction chamber at a temperature of 2h0° 0. Because of
the low boiling point (—100.8° C .),and consequent high vapor pressure
at room temperature, of chlorine monofluoride , this material was made

in small lots as needed rather than attempt storage of a large amount.

79

Each lot was purified before use by trapping (liquid nitrogen bath),
degassing, then vaporization from an isOpropanol-Dry Ice bath and dis-

card of any residue. Purity of the first one or two lots was estab-

lished by the ultra-violet Spectrum (Figure 38). Since chlorine mono-

fluoride is quantitatively separable from chlorine trifluoride by means
of an isopropanol-Dry Ice bath, the only probable impurity was chlorine;
the fact that nixtures of the monofluoride with the trifluoride under-
went little pressure change with time when emamed into the hot
reaction chamber was subsequently taken as positive evidence of purity.

Exchange Procedure

Tagged chlorine monofluoride was made as described above, then
expanded into the gas-counting chamber and counted at various pressures.

The activity was found to be essentially linear with gas pressure in

the regions investigated (Figure 39). Since initial experiments showed

that exchange did not occur at room temperature , chlorine monofluoride
was mixed in various ratios with chlorine trifluoride in the copper
expansion chamber of the gas-handling system. As in the kinetics experi-
ments , after mixing the reactants were expanded into the pro-evacuated
nickel reaction chamber which was kept at the desired temperature. The
expansion process was exactly the same as described in Section V with
one exception; imediately after reading the initial pressure, the valve
from hot chamber to pressure gauge was closed. This valve was kept
closed until Just before quenching, at which time the valve was opened

and the pressure again recorded. 111 the gas in hot chamber plus gauge

\_. ,

 

..dhnuuww manhomwuouofl. mlrwhoiran .mm mhdbwm
.

I(

83 moo 8mm 8mm 8% . 8mm 88 8mm 8% 85..

c, v. , e _ no

0
N .
a
s; r\
L. can
u
w e
0
a L m2.”
e
a
H Meagan mom 4 no A we ”must no nowmgomwv hem
.
2&8 mm W onsmmohm I O.N
P. _ _ a my _ _ _ .L _ _ _ _ P. .—

 

 

m.~

flousqsosqv

81

 

.msusmmoha oceans» as sewaosawosoe ocwnodno m>wvumowflmh we .mpwbwuoa .mm mhzmwm

.65 5... anemone Manta—On
00m 0mm com 03” b0...” bm

_ 4» L1 _ a n

I tom

18..

l
C
an
H

 

 

mes/91.1mm tr; £1111;qu

82

was removed in the quenching process which consisted of condensing the
gases into a trap surrounded with a liquid nitrogen bath. Quantitative
separation of reactants was effected by distilling chlorine 'nonofluoride
from the mixture of monofluoride and trifluoride at isopropanol-Dry Ice
bath telperature (Figures 110 and 111) . Chlorine monefluoride was expanded
into the gas counting chamber and counted at a known pressure. After
counting, the monofluoride was removed through the soda-lime bottle.
Next, the residue from the distillation was purified by one or more
vaporization-condensation-degassing cycles to remove traces of the mono-
fluoride, then expanded into the counting chamber and counted at a
known pressure. Because the pressure of the gas counted in some in-
stances was low ( < 50 m.) , and because the gauge calibration over a
period of several months fluctuated by as much as three millimeters
(Figures ’42 and 113, and Appendix II) causing a relatively large error
at very low pressures , the chlorine nonoflueride fraction was counted
at the same pressure as the chlorine trifluoride fraction,td.th few
exceptions . In this way, possible error caused by gauge fluctuation
was eliminated, for the fraction of exchange was calculated from the
activities of each gas after reaction. Retention of total activity was ,
in nest cases , ninety per cent or better. Activities of the separated
reactants varied from about one to twenty counts per second above back-
ground; individual background counts were taken before each sample

was counted to eliminate error due to adsorption .

83

.mnwaosamoco4 mcflmomqo gosh J)ps

OONJ

eons

00mm

we
omen ooem

newsmao>ms
. comm.

q

seem vsflaosamwpp mcwhoano mo a

ooom .
_

«4)

~ ff 1
r (\

)43w...»

\1 4
{H012in 904:... r....\.rpl.v, "r.

Down Oowm
_ _ A _

ooqm

 

’l

 

A} _

_

..en

’fi
'D

O

'1
t.

H Nassomma mom

4 OOQA we seen we cowmmSomflU now

.EH om N madmmoam

N

\\

t‘

a
0
’t

.4

3

(D
O

m.o

O.H

flounqsosqy

.. o.m

 

‘44 m.m

 

 

.mvwnoSHHHhu sawhoano scum usumnmnmm seahonfiwonhmvonfiLOMSo mo.a:huuoam .H¢.mpsmwm

comm
q _ d

OQN¢ Door Down

 

ca 8 W £5.01“th

s sfl npmnoao>mm

and 8~m8om 8mm coon
.____.____

O.H

 

 

Kausqaosqv

r.)
o0

.momnmm gauges. new age cowamunflfimu smooth .3 show?“

.ae cw onsmmoua fleshed

 

 

 

 

  
   

8m 02. _ 08 8m 8: 8m 8m 8e . no
_ — _ _ q _ _ v _ _ _ fl .q _ x lo
.103
1
18m
loom
ildtlf84~
1
18m
1.000
L
181.
48m
_ _ h a _ _ _ _ _ _ a p r . _ .

 

 

man u; eanssead eanS proonen

86

com

cow

.uowsew Sosa—Hem you 0:50 dang BMW 0&4 0.5mm

9E: 5 ouswoohm 33
000 00m 00: com com

OOH

 

 

\‘\
r-— “ .9

_ _ _ _ a _ n a In

owsww O

&'

2.4m Au

 

 

 

OOH

CON

OOIIGH

0 s s
5% 1: «x
‘mm at eanssead eBneS p;

53
\0

E3
[x

com

87

Results

Chlorine exchange did not occur between gaseous chlorine trifluoride
and gaseous chlorine monefluerids in the copper vessel at pressures of
about six Insured millimeters of mercury and temperatures up to 165° C.
Exchange did occur when the temperature was maintained at 200° 0. for

one home.

1......”

Quantitative results were obtained frem experiments carried out F
in the nickel chamber. Busing. was studied at about 203° 0., 2.21;" 0.,
and 2160 6., as a function of the concentration of each constituent.

'I‘:*_"" - '*

The rate of exchange, R, was calculated for each individual experiment
by the following method (See Section IV) .

where t - time in minutes and brackets denote concentrations ,
calculated by the ideal gas law. The fraction exchanged, f, at time t,
was calculated from the relationship

(experimental fractional activity in 011‘.)

 

 

55) .r ' (tutor-Rica fractional activity in 011., at equilibri; (r)
where F - fraction of gas in hot chamber (exchanging) - VR
Ts

YR - volume of the reaction chamber - 311.9 mi.
'8 - volume of gauge - 19.6 ml.

'1'}; . temperature of the reaction chamber in °x
T8 3 temperature of the me in .K, I

88

Per emples er this calculatien, consider the cases:

1. Exchange betuoen a lixture for vhich 011' + of? 8 cu, - 2:1
ath‘I}. [where 'rg - 301' K 3 equal amounts of each gas
counted after separation;- activity of 01*F - 6 counts/560.;
activity of oft, - 2.5 counts/sec.

‘ 311.9 9
th°n ’ '“3i575'17i573'Igzgi ' itifv

30].

7736‘s
and f _ . + x

(3) (231.51%)

2. Exchange between a mixture for which 011‘ + 01*? x cm, - 1:2 at

h73° x
where Tg - 301° K 3
equal amounts of each gas counted after separation;
activity of 01‘! - 10 cunts/no.3 activity or 01‘1", - 2.5

counts/sec .

2:2
fr2:+

<§) (3%?)

The rate of exchange , R, at constant temperature was plotted as a
function of the concentration of chlorine trifluoride, with chlorine
mononuoride being held constant, and also as a function of the mono-
fluoride with the trifluoride being held constant (Figures his through
51) . These gaphe indicated the rate o£-exchange night be proportional
to . the square root of the concentration of each constituent. Although
a second possibility ulllbe discussed later, consider first the
functional dependence

89

 

 

 

I T If I T l I I I I ]
(ClF3) - 2.1mm.-3 moles/l.
“F- —4
VI
53
’1
as
d
E.
3
a!
2
l
0 1.311121111111

 

 

0 , 2% 1+ 6 8 10 3 12
Chlorine monofluoride concentration, moles/1.x10

Figure 4h. Chlorine trifluoride-chlorine monofluoride exchange at 203°C.

 

I e

 

I .,-, .\ ' -J H a I
K-JJ-L.) g; {a . I‘x LA) 'll'.) [Jib/.1. e t

5

R, moles/lnninJlO

 

 

 

 

0 i. ii l J L fl L l I I l .
U' ~ ' l? 6 8 10 3 12
Chlorine trifluoride concentration, moles/1.xlO

Figure 1+5. Chlorine trifluoride-Ichlorine monofluoride exchange at 203°C.

91

 

...J
“o
H
5
Q
m
0
'§
Q
a:
d
_

 

 

 

 

0‘ ! 2L“ :4 t be ‘ri
‘ 3

Chlorine monofluoride concentration, moles/1.x10

Figure h6. Chlorine trifluoride-chlorine monofluoride exchange at 203°C.

92

 

 

 

 

 

“O
....
5
F:
.a 3 -4
Q
m
0
....g
8
a?
2 ..
1 ‘ -
0 L I. L J I I l I I . I I
W I ‘ 1+ 6 8 10 12

3
Chlorine trifluoride concentration, moles/1.x10

Figure 47. Chlorine trifluoride-chlorine monofluoride exchange at 203°C.

S

R, moles/l.min.xlO

Fi giro 48. Chlorine trifluorioe-chlorine monofluorice oxcnungc at ‘2;

12

10

CD

0‘

 

 

(cm) - 2.“ 10'3

l I l I
2 h

moles/l.

I
6'

v

I
8

I
10

 

_i1

3

Chlorine monofluoride concentration, moles/1.x10

 

93

9A

 

I I I I I I I I I I I
1h I. .4
~ , -I
12 - _
(ClF) - 2A x 10” moles/l.
lo I.— ....

_
W
O

A _.
E

86%
a?

r:—

A...

I.—

  

.=(ClF3) uncorrected for dimerization

 

 

, . I I I I L ‘ I I I I I .
O .. .. I, 2 t it 6 ' 8 10 3 12
Chlorine trifluoride concentration, moles/1.x10 '

Figure #9. Chlorine trifluoride-chlorine monofluoride exchange at 221+°C.'

95

 

S

R, moles/LazinJlO

 

 

 

0 J i I I - I, L L I L I I
1+ 6 8 10 3 12
Chlorine monofluoride concentration, moles/1110

Figure 50. Chlorine trifluoride-chlorine monofluoride exchange at 215°C.

~§

96

 

 

I I I I I I I I l I (I
JAI— _I
1" (ClF) - 2.h Ith_'3 moles/l. "
lZI- I
I- /-—- — _ — _ *—
/ o
10 - / / d
I-— / O —I
mg /
’5 8 " / '—
.g G)
g r- / A
0
H
3 6 I- / _F
e? G,/
__ / -..—.. (ClF3) uncorrected for aimerization ..
1+ I- --I
— -I
2 I l "I
.4
o I. I . I I, I I I I I I I l I
(I ' 2 6 '3 10

Figure 51. Chlorine trifluoride-chlorine monofluoride exchange at 245°C.

 

 

' 3
Chlorine trifluoride concentration, moles/1.x10

J I .I“

“GM try.“ :9. a. -

‘2‘:

97

56) a - x \W,
where X - sons constant
felt.) . concentration of chlorine trifluoride in
moles/l.

(Cl?) - concentration of chlorine nonoflucride in
. moles/1.

Consequently, R/ W should be constant at constant
taperature if the postulated relationship is correct. That this
relationship is indeed rolloved rather well is shown in Tables VIII, 1:
and x, in vhich valmsfer R/W at 203.II° 0., at 22h.3° 0.,
and at 2hSJI° c. are tabulated along with other pertinent data.

I
I:
I:
ii
I'.
I

 

looming that 56) is followed, then

57) x... - (Ia/mm... I r mm

It is therefore possible to calculate the theoretical value of the rate ,
R calc., at the measured concentration (and temperature) of each experi-
ment , thus

573) Beale. " Kw. Illegal [an]

The values of Rcalc. are given in Tables VIII, II and X. In addition,
Rcalc. values were plotted on the graphs containing the experimentally
determined points for B vs. concentration of one constituent (Figures
III; through 51) , and a smooth curve dram representing the theoretical
curve obtained from Rcalc. Rather good agreement between theoretical
curve and experimental points as found.
Prone plot (Figure 52) of K". versus :15,
for the exchange pas calculated to be 15.9 heal/mole.

the energy of activation

98

HI I. . .I.
. w.
ab 1.3 ”1'. 5.01.4» ....Jo’lii‘. a W EON . In By

.33 133.8 ton HH #8234 com a

 

Red :36 cme. N 8de N43. Henge. 8 mH
0H»; «and mNH. m Home. o R.HH mend. 8 in
2H; 23 me: 83. o and. RH.H on MH
21H mood EQH «on. o 03.». «84 8 NH
3H; 9:.» nNN.H Rem. 0 «SH c3.N 8 HH
30.; N86 2.94 Nmom. o 8: 3a.; 8 OH
emu... can. a. mend 33.0 mm»... «one 8 c
Sun 02. e as. m 89.0 to... to... 8 m
eNnN Nfi. a. cch Ham. 0 a... NR.N 8 a.
mango. come HeH. N 335 and $5. a 8 0
NSA m3. 4 NRJ SNm. o mo.HH SQN 8 m
EQN 3H. m HmH.N mad 2H; Hem. N 8 ..
mun; NMN. c «3; 3.de 8nd 8m.N 8 m
ammN Nch on...“ 2&6 o3...“ cHN; 8 N
and 83 2b.... 386 2QN $.HH 8 H
leeway. on. $37. a. €35... .. :ch $3

oHoa inflows) eHea a ...QoHee . 32. a... on: aches
..Keem . .me 1.3: 43: powered esteem

 

.c cancN .3 Each damage: gagged. ago an. a e853, gear
5» an:

99

has“ an}!!! . ’9 “.,..!l..‘. lid: m r

3% HSHNHB you HH 523% com m

l E '

 

 

mwmé omdugd
HNNA 0Nm.H Roi 800.0 00N.m 0mN.H on 0N
03.0 024 Nam 0000.0 HNH. N find N N
20. N 0m0.H 3N. N 00Nm.o mNm. N NNH. H N 0N
80. N mH0.H 3N. N SR. 0 moN.H 03. N mN mN
NOH.m 4004 NN4.m H43. o $0.: 0%. N mN NN
NHm.m SN.H HNO.m 300. 0 an. N «0%: N HN
N030 NNm.H N00. N gm. 0 RAH «R. N mN 8
443.0 mm: 030 0N0m.o mNm.0 mNN..N mN NH
0 N0 . n 30. H 05. 4 N80. 0 oS. N 03. N mN 0H
N30 N00. H 08.0 0NH0. o fin. N HNH. N mN NH
H030 Hum; 84.0 800. 0 4%. N N0.HH mN 0H
$335... Nod" 7.an $03.5... «2.3 nods . .
. Quoaoa n . (mono.- u . 3H3 . undo: A. 325 02.3. .3955
1&8 E8

.013 m - , m owning—M. H6333

>

.o omiwu ad ”fin—mum Man—”83.320: Egan—HESS“. go 8.3. a #38 macs-um
NH...§H

100

m . . 1.1.153.
Fr)...» Fr: tillntunlllullL'

00% H4538 .3 H 300% mom ¢

«me. u owduobd

I'll ‘

 

000.0 mHH.N $00.0 HmNé m0m.N mH Nm
N93 053 N200 mmmN NNH.H 0H 0H
No.3 .30 0000.0 NNH.H mmmN mH mm
08.0 0N.0H $00.0 m0m.N HNN... 0H 4...
0N.0H NN.0H 020.0 00.HH 0NH.N mH NH
RAH NH.NH 0H00.0 00.HH and 0H Nm
NN.0H 00.0H N0Nm.0 Nm0.N «mm.N mH Hm
30.0 H0n.N 0HNm.0 0N0.N 0N;.N 0H 00
00.HH HH.0H NNde 0Nm.N NNH.N mH 0N
0N.0H 00.0H NHmmd 00.HH 0Nm.N mH 0N
m0.0H 8;: Nfimd HN.0H HNm.m mH NN
$33.52. $03.03 00an $803
..Qnoaoa ..QuoHoB u . uoHoa . 0308 @503 05.3. .8952
602% a Th3 CH0. 0059a 03083

 

? 'r 1“!“
if It! I!

.o 0:. mam 94. 52mg magbggz gmoéunmamogs gage mun. 2H two—imam moon—385m

N ands

 

 

 

 

60
' l | I
L— .—
h0*- '-
r— —--4
20- -"
n
O
H
X
° -— -1
8 10
{ *" "
"" 3.. .4
3
, b .- --
“no
6- ....
n— .d
15" --I
F'" 4-—
2 I I I
$.10 1.90 2.00 3 2.10 2...0

l/T, degree" x 10

Figure 52. Arrhenius plot. for chlorine monofluoride- chlorine tri-
fluoride exchange: homogeneoue mechanism.

101

'15 _ fizz-in? unit-g“ .I J: ”.3. .

102

'The activation entropy for the exchange was calculated to be 446.0
e.u., assuming the order of the reaction (21) is one.

There is a second_poss£b1e functional_dependence of R.on the con-
centration of constituents. Recall the Langmir adsorption isother-
(equation 6, Section IV) . If B were preportional to the fraction or

surface covered by both chlorine trifluoride and chlorine nonofluoride ,
then

58) R U Kgcnagcl? - Kibc]: bCHICH'] [01?]
[1 + 1361,4013] + bcuEGI-‘Fl 18

 

where K; - specific reaction rate constant in moles/Lesa.

1361?, ' be]! - b, some constant (assumed equal for
both reactants because of the similarity of
rate dependence on each constituent.)

or
59) a - x. 0' [01151 {031_
t 1‘+b ((611.1 + tom) 1'

60) VW] . -\/I MW

[1 +b ((65.1 + town"

61)er .W.W1
_ ' W113“ VIC; m

Equation 61) is a linear equation; experimental data were plotted and

 

 

 

a line drawn by the method of least squares, from which K‘ and b were

obtained by the relationships

62) 81°” 3 all“-

W?

63) y-intercept -‘ 1

h \[K‘

 

 

103

The values of [A and b at the temperatures of the experiments are given
in Table 11. These K; and b values, as well as equation 59) were used
to calculate the theoretical rate, as , for various experimental values
or reactant concentration. The a, values obtaimd are listed in Tables.
III and XIII; these same values were used to paph the theoretical
curves, assuming heterogeneous catalysis, in Figures U4 through 51.

Iron a plot (Figure 53) of [1 versus l/i‘ , the energyv of activation
for the exchange was calculated to be 11;.3 huh/mole . The activation
entropy in this case was calculated to be -67 .9 e.u., arbitrarily taking
the order of the reaction (n) to be one.

Discussion

The main sources or error in the exchange experiments were
1. Possible errors in scanning tsnperature and pressm'e.

2 . Possible incomplete separation of reactants , because of ,
for example, snriace adsorption.

3 . Statistical errors inherent in radioactive counting.

In scene instances, the net counts per second were only one count
per second above baclqround activity; it is therefore of interest to
exemplify the magnitude or the statistical error. Consider the case
of a background count of 600 counts in 15 ninutes, and, with a sample
in place, a total counting rate at 1000 counts in 10 minutes. II'hen (33)

MW' snipe; -.ho_- 1. 6 counts/min - 0.66 I 0.021
counts/sec.

.WOO -1oo 3.2counta/n1n.-1.66-o.053
Rtotal counts /sec .

%et-1m-h0- -V'I'.'B"""T!", -60-3.6counts/nin. -l-0.06

counts/sec .

 

 

 

10h

TABLE II

CONSTANTS ARISING FRO! THE APPLICATION OF THE IANQIUIR
LDSORPIION ISOI‘HERH

A‘ _._ ‘

 

‘ M

m

_.___‘ “—

 

 

_ -+
x
'1‘ raturs b 1
£8. l./nole mole/l. ”1113103 F]
203.1: 103.6 0.6238 :l I. 2
2214.27 110.6 1.361 5
2145.38 165.3 1.627 Li

 

f Equation 5 8

 

 

TABLE HI

mmocnmous 1110317701: 117 THE owns TRIFLUORIDE-crmoams
nmarmoams. stern: 11' 203.179- 0. . .

 

 

Reaction [011,] [011) 31
Number moles/1.x 103 moles/1.x 10’ moles/l. min.

1 2 .378 11 .89 3 .080 Ema

2 2.1706 7.219 2.915 1
3 2.389 2.389 1.709 g;

b 7.113 2.381 2.881. '
5 11.85 2.370 3.073 ,1

6 2.383 8.767 2.550

7 17.7104 2.372 2.1496

8 h.677 17.677 3 .776

9 .17.755 9.509 17.930
10 9.2789 11.7171; 17.921

11 1.203 2.1706 1.026

12 2.1.06 1.203 1.026

11. 11.97 2.395 3.098

15 7.1h2 2.381 2.88h

 

106

TABLE XIII

HEIEBOOEIEOUS Emcnxncs Ix'was<cnnonxlnzraxrzuaaxnshanonINE:unuarLuaarnE
5131104 11' 228.3° 0. m0 285° c.

 

[013.] [01!] a.

 

 

8.731

Rm? rmgttm Idea/1 .310: ”108/1 31°. ”1°’/1 ”.1105
16 228 .3 2 .3717 11 . 87 7 .063
17 2214 .3 2 .378 7 .121 6 .691
18 228 .3 2 .830 2 .830 h .170
20 228.3 11.90 2.379 7.079
22 228.3 8.639 2.320 5.717
23 228.3 1.203 2.806 2.860
28 228.3 2.378 1.189 2.819
25 228.3 7.121 2.378 6.691
28 285.11 11.88 2.376 11.11:
29 285 .h 2 .376 7 .127 11 .39
30 285.8 2.870 2.870 8.217
31 285.1; 7.059 2.353 11.30
32 285.8 11.90 2.381 11.15
38 285.8 2.365 8.731 10.53
35 285.8 1.177 2.355 8.913
37 2115 .17 2 .365 10 .53

 

 

60
808-
20-

t

9.

I

g.—

7-1 .—

€88-

.2 _
6 n-
h.—
2
130

 

 

I

l
2.00

8.118

11L!

1

 

 

 

1.90

3
l/T, degree" It 10

Figure 53. Arrhenius plot for chlorine monofluoride-chlorine tri—

fluoride exchange: hetqueneous mechanism.
0

107

 

 

 

108

Because the example chosen is essentially the lower linit in not count-
ing rate above beckground, and is much less than the total counting
tine used in these experiments, the error shown should be the 709.3de
error caused by low sctivities. Overall error 13s eetinted to be
within ten to fifteen per cent. The ectivation energy is probably
accurate to 3 1 keno/nae and the activation entropy to t 1 e.u.

The behavior of the rate of exchange, R, with the change in con-
centration of constituents can be interpreted in terns of either e
haeogeneous mechanism, or heterogeneous catalysis. Both arguments will
be presented.

The case for a Mneous mechanism. 1 homogeneous neclnniss for
exchange would here to predict the dependence of R on the square root
of the product of reactant concentrations . The calculations deter-ining
the dependence of 3 upon reactant concentration for a particular
nechanisn are difficult in exchange reactions because sons resctants
and internedietes are tugged, and hence different (nlthough chemically
equivalent) from the corresponding untagged species . Ior simple
nechanisns, it is possible to express the rate, %, (cf. equation 22)
of increase of tagged atom in species 11, in terms of the rate con-
stants end constituent concentrations appropriate for the equations of
the proposed nechanisI, equate this 5% to the equivalent g?" used in
deriving equation 22), and find a in terns of reactant concentrations
and rate constants of the nechenisn. Ln emple of this treatment is
(1) in the 11st of mechanisms (see pegs 109). Somewhat more complex
mechanisms can be treated by the nethod of Karma (38), which is

 

 

 

 

109

related to the process outlined above but involves simplifying
asmmptiens. Thus Marcus lots 31* be the concentration of those
BX-type molecules which are tagged at time t, and defines the Label"
such that it vanishes when the specified atom enters a position in an
AI-type molecule, but not when the specified atom enters a position

in one of the intermediates. Bx* decreases steadily aith time from its
value at t - o to zero at t - o0 . Lemming no reaction between two
tagged molecules , Marcus derives

j
a» My?! )-(e-:-:-'->
where b - total concentration of BI-type molecules
in atone/unit value.
in example of Marcus' method is (B) in the list of Mechanisms tested.
Selle mechanism“ tested were the following:
(A) Standard method, reproduced in detail.
' ' on. 15+ on + r,
C15. ll; 01*! e r,
01? fl, 13—) 011',

I
01*? 9 r, 4") (31.13

94-31-932 - gt: - :3 (C15?) (r3) - x1(01*r,) - K,y(F3)-K1 3:
car.) - o - xl[(cn,)+(01*r,)] - x.[(c1r)+(c1*r)](r3)- K‘s-biwz)

(F).x‘
= fir ,
3% -K1§§-xlx .x1(§§t.’£) IR? (by equation 22)
R -K1"

or the rate is proportional to (CH3) total.

 

f The notation of equation 22) is frequently used for simplification.

Jobs-r e .....n (I “W‘- q‘
:. ._...I‘“ r- ‘ 7

W
Y
I

 

110

(B) Maren? method,reproduced in‘detail.
l
+ :3 2011",z where it -FC].FzClF complex

K-1

01:, 4 01'? la; Cl’fira + 611'"
c1*r, e 01F. _x_,_> 011‘. + 011-",

- (1531;?) . x. (cu-3) (01*?)

1 d 01"?)
.. . K
01'? dt 3 (0132)
d 011'" )

dt " 0 8 2K1( 1‘) "' K.1(C1F a) z-K3(CIF3) (Cl-*1?) +K3(CI*F2) (CH 3)

subtract flag-ll - o - x4013.) (01*?) - K4015.) (c1F3)

2x10) - 1g,1 ((3113)a
(cure) .\/ 1::— \l’ ( '1')

W - ......- as???
Ii
I
I

l dCl*F)
~75? 43;— - Kat/r“: V??? - .g.

R' 1‘2 V4??- hm—

or the rate is proportional to (cuntotal / concentration

 

of
complex

(C) Reaction sequence Final elqlression

ex) 01*? + emf—9 01*}?2 + 01?; assuming
$015“. + 01Fa ——+ 01*F + 01?,

d(Cl*F3) . o . d ClF )
c1*F,, + 0115—9 cm + 01Fa

dt

2;) 01%. + 01?, —> 01Fa + 01F,
R ' K (01F)t0t31(01F3)

a K I: (a-x)

5) our. + 01*? :3 01F + 01*};

 

 

111

(D) If for 04) in (C) above

ClF 4» CH3: ZCle is substituted,

the final expression is essentially the same.

(E) If a), X), and g) are used, in conjunction with
011,: (3le 4-?

assuming
4* {-
Cl r + F ——>c1 F2 d(ClI-‘3) do?) _ dgcf‘Faz
* T‘t 3? dt 0
01 F3 + F —-) CH3

 

a

R - K (ClFs)(CIF)tom 1- K(ClF2)
(01F)2*(01F3)1

No method of eliminating the

Very complex mechanisms can be treated by the equilibrium method
of Sternberg (39). This method is based upon the fact that exchange

reactions are assumed to occur in a system at dynamic equilibrium, in

which R is constant throughout a given emeriment. This condition ‘

necessarily inplies the presence of equilibrium concentrations (independent
of labelling) of reactive intermediates as well as of stable reactants.
Equilibrium concentrations can be evaluated with the usurption that

the concentrations of reactive intermediates are negligible relative

to the concentrations of stable species . With the additional assumption

that the concentrations of tagged and untagged intermediates at time t
are those obtained by the instantaneous equilibration of a mixture of
the tagged and untagged reactants having the composition existing at

time t, the individual concentrations of each of the tagged and untagged

intermediates can be calculated. Using the concentrations of

 

112

intermediates thus found, an expression for the rate of increase of
bagged atoms (—-) in molecular Species II, or the equivalent rate of
decrease of tagged atoms (71%) in molecular species BI, is written for
the postulated mechanism. This expression can be reduced to the

Torn

65) %--§{-u%-n%x

where % a rate of increase of tagged atoms in species 11.

N - function of the concentration of the molecular
species IX and BI, and of the rate constants for
the individual steps of the postulated mechanism

a, b, x, a have the same meaning as in 22), Section IV.

however, this dx/dt is the same dx/dt used in the original derivation
of the exchange rate, R, where (of. Section IV)

22) er RE (ht-R: (12,31) .mel-EF—bx)

01‘

66) 3.1;

s _ a+b
dt R

B '75 x
By equating coefficients of either z/b or éab/agx in equations 65) and

66), R is foum in terms of _a., ‘3 and the rate constants for the steps
of the postulated mechanism.

For a possible mechanism in the chlorine trifluoride-chlorine

monofluoride exchange, consider the following application of Sternberg's
method.

If pertinent equilibria in the system are taken to be
K1
67) on —-‘ c1 + r
b

T_——"

K3 C d

L. . V '

 

 

113

 

68) CH, ; CH2 4- F
a X, f d
K.\
69) CH 4' F (.....- CH3
b d K6 1’
K1
70) r + r -—-‘ F,
d d K. g

where a b c d f g are equilibrium concentrations, then on the
basis of the equations
Kxb-Kacd Kgbd-Kgf
xaa-x,rd [Coda-Keg
explicit solutions for c, d, g, and f may be obtained in terms of a,
b , and the rate constants. If, now, the molar contributions of
equations 67) 68) 69) and 70) are considered to be 1, m, n, and p
respectively, that is, equation 67) contributes 1 moles of Cl and 1
moles of F, et cetera, then the total moles of each constituent are
01 a c - 1
F a d - l + m - n - 2p
01!, - f 2 m + n
1"a ' 8 " P
Since c, d, f and g are known, 1, m, n and p may now be related to
a, b, and the rate constants. For example, 71) m - g + W .

m M, a 1 W722: 21V???-
KTux‘Ka b +2 K;63

72) d - “1.9.... and so forth.
K‘KQC

 

 

1114

A particular mechanism leading to exchange may now be selected.
Consider the following steps
73) cu. —K—’—> our. + r
71;) 61F; + 01*!“ 19—) 01.173 + Cl? and 79) F + 01*1‘ -—KL) 01‘”!a
75) c1'r. e 011' 13) 01?, + C15 hr 80) 015', is 01*}? + r
76) 01*}?a e 011'. 559—) 01*r, e on,
77) on, + c1‘r, l{33> c1]?a + c1573
78) 011’; e F 53—) 01?,
For this mechanism
alloy? - K.(c11v.)(cmr)-x,(c1*r.)(01r) + x.(r)(c1*r) - Item’s.)

82) -d c1‘r . x,(cu.)(c1‘r)-r.(01*r.)(Cl!) x.(c1*r)(cua)eq—x.(01*r.)

99
by equation 69)

but
(01F) out
a (Mam mm m f ‘ ¥
, (01*?) (015' )
81:) (01.15) (mm 1 en e (write .1. :- ¥ + 9.3.“.

85) (r)-l+n-n-2P~d

86) (01F) - b

87) (of!) - z - 1
hence '

88) -é$%%l)__ - K.: [a - x] -x,[ny ab?) +Ke(2§l£-Ke[3§ .35]
neglecting products of those constituents present in small quantity,

for example, :7. Making use of the relationship f - m + n,
39) “Lav—”15h Kembg-Kemb%x “o"E'Koméfix

 

 

115'

Therefore,

R - K, I b from equations 71;), 75) and/or Kgm from equations 79)
and 80) .

Using 71), terns resulting from 7h) and 75) are

x. x.x.x, a

90) a _ m + gay/If. ab ..xxx.‘ r ‘L b, aleab‘

w e

a e
Terms resulting from 79) and 80) which say be added, used alone or

discarded, depending on apparent validity, are

91,11,317 1.... m Law/cw, 53

xe‘exeb 2 ‘a‘sb 2Ks ‘axe‘ 2 xe‘e

Although it might seen that some rationale could be advanced for the
contributive importance of those terms involving the square root of

the cencentration product, examination reveals that the important terse

are not those which are desired. Each tern involving the square root

of the concentration preduct also involves

’55:
‘e‘s

which is found to be about x 10" at 203.1;o c. by using the thermo-

dynamic data in Table III, Section II, in conjunction with the relation-
ships

xaxe [01'1"] [7 l 6
92) m W from 68) and 9)

and

wu-m‘ —7“-I'F——'

 

93) Ar-o- AP°+RTan

P

where nr" - Al'flClF) + 2 nt,-(1r) - Arf(c1r,)
x

- pressure quotient (at deviations from
p the standard state of l ats.)

. Kaxe
We .
Sililarly ,

_ is
i: 1.2 x 10

The values given above have been converted to concentration unite to

facilitate comparison with experimental data (calculated in terms of
concentratiens) . Pres tines facts, it is seen that the terms in 90)

and 91) involving the square root of the concentration product are
ceapletely overwhelmed by the first terns . There is no possibility

that I, in term two ef equatien 90), for example, is large enough to

overcene the ‘q/xa ratio in term one of 90) This follows because I,
is calculable . Censider the case of term two in 90) alone being

important . Then

9“) “WEVT “humid?

e
and experimentally

56) n-x V'IB’

which indicates

95) fit: _:.\/76:lo

 

? See Table VIII.

"by"!

W ‘n Hm".
‘: i

 

117
O
or at 203.h c

.s

x, '4 2“.” x lo ) - 0.502

V7.6 1 I5"

Although other reaction mechanine were considered , no combination was

found which escaped the above dilemma.

There have been few homogeneous exchange reactions reported in

which R was not proportional to the first power of reactant concentra-
tions .

However, Gryder and Dodson (ho) found the rate of exchange of
Co 111 to Co Iv in aqueous nedia varied as (c. Iml (Ce Iv)“, where
n varied from O to 1 depending on the nodiun. Also, Boggs and Brockooy
0‘1) found that the rate of chlorine exchange between gaseous 03,01
andml at 360' c. to MS0 0. was proportional to the square root of
each constituent concentration. Unfortunately, no mechanisn, or

explanation, for this behavior was offered , but it was shown that the
reaction was homogeneous.

 

The case for a heterogeneous nechanisn. Unless a large snout of
infornation about the system has been obtained and correlated, nechan-
ias for heterogeneous reactions are seldom offered. Usually a low
activation energy and a large negative activation entropy, along Idth
difficulty in predicting the rate dependence on constituent concentra-
tion by a homogeneous mechanism are taken as good evidence of hetero-
geneity. Differences in rate with variation in surface area are
usually indicative , but in the very analogous chlorine trifluoride and
fluorine system, Ada-s, Bernstein and Kata (16) were not able to find

any such correlation, even though the exchange reaction appeared to be
heterogeneous .

 

“m1: .-. ar’qu- fl

118

Farrar and such (h2) have shown that chlorine trifluoride is
adsorbed strongly by nickel fluoride; the adsorption is Langmuir-type
adsorption. Chlorine sonofluoride night he expected to adsorb on
nickel fluoride strongly because of its relation to the trifluoride;
it has been shown (183), however, that chlorine, which is also somewhat

sinilar to chlorine nonoflueride , does not adsorb strongly on nickel
fluoride .

Final considerations . Although the data do not uniquely deternine

the dependence of R on reactant concentration , they do strongly suggest

that R is proportional to the square root of the product of reactant

concentrations. It scene inportant that those experimntal points in

Figures Us through 51 which indicate that the adsorption curves are
obeyed are, in general, points which were obtained without correcting
the pro -reaction-chlorine trifluoride concentrations for diserio ation .
If the chlorine trifluoride portions were corrected for dinerination
using the data in Table IV, the rate, R, increased sonowhat, and showed
approximately square-root dependence on the reactant concentrations
(see Figures 115 and $1, for example ). It also seems isportant that
in Tables 1m, 11 and x, the coltun listing R/W values
(in reality the specific reaction rate constant, K, asstming square-
root dependence as in equation 56)) shows rather good constancy. This
criterion is perhaps sore reliable than Figures M: through 51, since

in the tables, all data obtained at a given temperature nay be
represented, whereas the yaphs in Figures M: ttrough 51, by their

very nature, are linited to eons port of the data at one taperature.

4' w in

119

If R is dependent on the square-root of reactant concentration,
then it seems reasonable to suppose that exchange is tahng place by

a homogeneous nechanion. There are other supporting factors. First,

if the nechanisn were not hosogeneous, then results should be dependent

on the history of the reaction chamber. The data were obtained fron

experiments between which, in nest cases , the chamber history varied.
For emple , only a few data were obtained with any one lot of chlorine !
nonofluoride . Each new lot of the nonofluoride was node in the same 1r
chamber used for rate neasurenente; this would be expected to alter
the chamber surface . Then again, all experiments at one temperature i
were not done consecutively, nor were the concentrations altered by

periodic dilutions; rather , variations were sonewhat at randen .

A second factor is that the system under discussion, chlorine trifluoride-

chlorine nonofluoride is very sinilar to the systen discussed in

Section V, chlorine trifluoride-chlorine . Initial pressures of reactants

were conparable, and the sons tesperature range was covered, all in the

identical reaction chanber. These facts, although not absolute evi-

dence , do indicate a high probability of similar nechanisns in the two

systens, and it is difficult to explain the data of Section V in terms

of awthing but a homogeneous nechanisn. lttenpts to explain the

second order rate dependence of chlorine lonofluoride fornation fres

chlorine trifluoride and chlorine in terns of a heterogeneous nechanisn

neet with a contradiction. The observed rate dependence would be

expected to arise through a heterogeneous nechanism only if both re-
actante were weakly adsorbed (equation 7), but it is known (lo) that

chlorine io adsorbed such loss strongly than chlorine tri fluoride .

 

All considerations, then, seem to indicate that chlorine exchange
between chlorine trifluoride and chlorine nonofluoride occurs by a
henegeneous mechanism, with the rate of exchange proportional to the
square root of reactant concentrations. No mechanics consistent with
such a dependence was found.

 

 

121

VII. THE CHIDRINE HONOFHICBIDE-CIEORINE SYSTEM

Introduction

In the previous sections , chlorine atom exchange between chlorine

trifluoride and chlorine as well as between chlorine trifluoride and

chlorine monofluoride was studied . In order to include all pes sible

combinations , exchange between chlorine moneflueride and chlorine was
studied .

Materials

All materials used in this investigation were produced and purified
in the manner discussed in Sections V and VI.

Exchange Procedure

Initial amounts of reactant were measured in the gas-handling

system and condensed into separate traps by means of liquid nitrogen

baths. Care was taken to prevent contact of the gases in this measuring

stage. Because of the high vapor pressure of chlorine monofluoride at

room tauperature , special techniques were necessary. The monofluoride

could not be warmed to room temperature in the measuring trap; conse-
quently this material was expanded into the volume enclosed by tin
nickel reaction chamber, Helicoid gauge, measuring trap, and gas-

handling line involved, all being at room temperature . The chlorine ,

which as measured and condensed into a second trap before measurement

‘III-w- are”
’i “L

 

122
of the mnofluoride, was heated to room temperature in the closed trap

which was then cponed to the gas-handling system, and the chlorine

allowed to expand into the system containing moncfluoride. The assump-
tion was made that mixing was instantaneous .

After suitable time, the gas mixture was condensed into the

chlorine measuring trap by a liquid nitrogen bath.

Both chlorine tri—
fluoride and chlorine have a substantial vapor pressure at isopropanol-

Dry Ice bath temperatures; therefore, separation was effected in the
following manner.

1 copper bar one inch in diameter and ten inches
long was bored, with a drill just slightly larger than the chlorine
trap diameter, to a depth of about six inches.
heat conductor.

 

This bar was used as a

It was placed around the trap; the temperature of the
trap was controlled by the depth of immersion of the copper bar in a
liquid nitrogen bath. By suitable adjustment, a slow distillation was

effected. Only a small fraction of the total gas involved was needed

to obtain the activity, so that only the initial material distilled

was considered to be chlorine monofluoride and cotmted . For the same

reason, only the last fraction was counted as chlorine.

That this
procedure resulted in reasonable separation was shown by the results

of the first experiment.

Emhange Results

Chlorine exchange between chlorine monofluoride and elemental
chlorine occurred at room temperature. The first experiment consisted

of airing the reactants in equal amounts in the system at room

123

temperature, or about 29° C. Separation and counting of the reactants

was done after three different contact times. The same material was

used throughout. For example , after the first quenching, separation,

and counting, the reactants were expanded back into the original part

of the system involved in the exchange. This procedure, of necessity,

made some uncertainty in the exact reaction times, as well as some

deviation from the original temperature .

 
   

However, the results show
that exchange does take place at room temperature, as well as showing

that separation of chlorine and chlorine monofluoride was attained by

the distillation procedure used, since the fraction exchanged varied

we. _-.s. ..r. . ‘m-a myfi.u.zae
‘ ‘ ‘ . I. ‘
e 1,,

from 0.655 to 0.81;? to 1.0 for reaction times of 60, 160, and 1080

minutes, respectively. The second experinent was performed carefully
and was considered to be quantitatively correct.

Calculations were made in a namer similar to that noted in

Section '1, taking into account that elemental chlorine has two atoms

of the species tagged. Since exchange occurred at room temperature,

no correction for unreacted gas in the pressure gauge was necessary.
Thus

2 0 Cl? 261 1
96’3'12'2 W11“ ‘1":7
and for the case

a 1:1 mixture of Cl, 4 01:30]! at room temperature; equal

amounts of each gas counted after separation; activity of Cl"? -

'I’
22.10 counts/sec.; activity of Cl, - 85.73 counts/sec.
then the fraction exchanged

22 .10

+

f-2

Results of both experiments are smarised in Table II? . '

12).;

TABLE XIV
EXCHANGE"r IN THE CHLORINE HONOFLUORIDE—CEEORINE SISTEI

#—

 

 

 

Tenperature Exchange '[011'] [01,] R t 1/2
°K Tins bin.) noles . moles . f moles/1. a
(:10: (non m1n.(x10‘) m. r “A
_ - A __A __ 5: .
~29 ~ so 6.21: 6.21; 0.655 7.38 39.1
~29 ~160 6.21: 6.21: 0.31.9 h.91 58.7 i "
~ 29 ~1080 6.21; 6.21: 1.0 -- ..
27 150 1:57 1:57 0 .61149 1.938 109

‘u — u
‘— w“

1* See Appendix II for original data

 

125

Discussion

The main source of error in the experiments was the possible
incomplete separation of reactants, although errors inherent in radio-
active counting as well as errors in neasm'ing temperature and pressure

were possible. The overall maximum error was estimted to be ten per

cent.
The results of some exchange experiments involving interhalogens

or other compounds of interest are shown in Table IV, as reported by

various authors. It is pertinent to note that many of those emchanges

taking place readily at room temperature have been postulated to occur

through molecular complexes.
In the present case, it seems reasonable to expect exchange between

chlorine and chlorine monoflueride to occur through a molecular complex.
It is m (Table I) that chlorine trifluoride dissociates at elevated
temperatures to form A chlorine monofluoride and fluorine; as the
temperature is dropped, the rte-formation of the trifluoride is favored .
This means that the bonding orbitals in the central atom, chlorine,
change in a way to accomodate the extra fluorine atoms. memental
chlorine has essentially the same outer electronic configuration as
elemental fluorine , but each atom of the chlorine molecule has unfilled
3d orbitals , and therefore more potentialities for hybridisation than
fluorine . In a mixture of chlorine monofluoride and chlorine , it might
be expected that some intermediate complex could form, then break down,
in the process shifting the fluorine atom to another chlorine atom, or ,

in effect, causing chlorine atom exchange. It would be most interesting

:- ”13mm .

TABLE IV

SCHE EXCHANGE RESILTS

126

V‘—
H

 

w-‘nx ...-Lia... «In; ”‘91-? ‘11
. ~ r r
i

 

"‘

Reactsnts Phase Tupgrature Exchange. Probable Mechanism Reference
1 and 2 1 a3 2 4

HF 011‘, g g Room o + Intermediate 114
complexes

1! Brl'. g g Room + + Intermediate 111
complexes

5‘ 1!, g g Room o + Intermediate 1).;
complexes

IF BrF. g g Room + + Intermediate 114
complexes

I? 011' g g Roe: + + Intermediate lb
complexes

m! 9'. g g Room -- -- 11:

W 001;. g 8 RC” -' "' 1’4

H? F. g g Room -- -- 1h

arr, on, g g Room + + Intermediate 1h
. complexes

P, 01?, g g Roo- -- -- 1h

8! BrF. l 1 Room + + Ionic equilibria 1h

H! 011'. l 1 Room + + Ionic equilibria 1h

HF Brl‘. l 1 Room + + Ionic oquilibria 1h

is It. 1 1 Room + + Ionic equilibria 11.

as SbF. 1 1 Room + + Ionic equilibria 114

cu, sir, I 1 not: + + Ionic equilibria In

H? Na? g s Room + + -- 1h

01?. N“; g 8 R”. 4‘ -- 1’4

01!, Ba! g s Room + -- 1h

Brl'. New, g s Room o -- 1h

 

a ++ represents F“ exchange; + represents slow exchange; .. represents
no (or slight exchange. ’

(Contimed next page)

 

TLBLE XV - Continued
W
Reactants Phase Temperature Exchangeilr Probable Mechanism Reference

 

Land 2 1 and 2 °C .
F, Na! g 3 Room -- - 111
F. 01!, g g 181-257 + Heterogeneous 16
1’. IF, g g 181-257 + Heterogeneous l6
F. M. g g 181-257 + Heterogeneous 16
F, H! g g l9h-2S? o Heterogeneous 18
11:1 01. g g Room + Heterogeneous 19
m:- Br, g 3 Room + 7 20
HI I. g g Room 4» ? 21
01?. 01. g g 180-255 «9 Probably homo- present
geneous work
01!. 011‘ g g 200-215 + Probably buo- present
genes? work
n-t(c1r,) (cum
0].! Cl. g g Boon + Intermediate present
complexes work
1' cH.c1 m1 3 s 375-hzo + n-x(ca,01 bl
fiterogeneous
? cum m1 g g 1:20.510 + n-x(cn.rci) la
Heterogeneous
icmpi m1 3 s 360-h65 + 12.1:(09301) 72mm; hl
Ho-ogeneous
* cn,c1 m1 g g hoo -- -- m
03.? W e s too-500 -- -- h?
(more “F 8 8 hOO-SOO -- -- h?
01’s H? 8 8 1100-500 -- -- 117
C94 3 6 8 boo-500 -- -- h?
01",013 H! 8 8 boo-500 -- -- h?

L. A

f Pyrex system used.

..—

 

 

 

to study fluorine atom exchange between chlorine monofluoride and

elemental fluorine, in view of the results found in the system
studied.

128

._"- — o . , o -"L
‘5‘ 7- 777" .- _. .-
. . f
I’.

 

129

LITEUTURE CITED

1. H. B. Thompson, An Investigation of Certain Physical Properties of
the Halogen Fluorides, Ph. D. Thesis, Michigan State College (1953).

2. a. G. Sharpe, Quart. Rev., 5 115 (1950).
3. n. 11. Greenwood, Revs. Pure and ipp1ied Chem., Australia, 1 8t (1951).

h. J. H. Simone, Ed., Fluorine Chemistry, Academic Press, Inc.,
New Iork, 1950.

H. s. Booth and J. 'r. Pinkston, Jr., The Halogen Fluorides, Chap. h.

s. a. s. Booth and J. 'r. Pinkston, Jr., cm. Revs. 9; ha (19147).
6. 14. B. Panish, Studies of Certain P

hysical Properties of the Halogen
Fluorides and Their Hydrogen fluoride Solutions, Ph. D. Thesis,
Hichigan State College (195,4) .

7. R. D. Pruett, An Investigation of the Electric Moments of Some
Compounds of Fluorine , Ph. D. Thesis, Michigan State College (195k) .

8. O. Ruff, J. Fischer, P. Luft E. lscher, I". Lease, and H. Volkmer,
Z.angsw. Chem., .131. 1289 (1926) .

9. o. Ruff and s. lscher, Z.anorg. allgem. Chem., _1_7_§ 258 (1928).

10. 1.. Damage and J. Neudorffer, Cempt. rend., gag 920 (19118).

11. H. Schmits and H. J. Schmcher, LNaturforsch" g3 362-3 (19M).
12. 0. Ruff and H. K1113 , Z. anorg. allgem. Chem., 129 270 (1930).

13. C. r. Swinehart, Private comunication, Reference number 11.2

it. n. r. Rogers and J. J. Kate, J. In. Chem. Soc., 11; 1375 (1952);
Argonne National Laboratory, ARI-11711, (1951 .

15. R. a. Bernstein and J. J. Into, J. Chem. 9113s., §_6 885 (1952).

16. 11.14. Adams, R. B. Bernstein, and J. J. Kate, J. Chem. Phys., 22
13 (1951:).

17. mt. Dodgen and w. r. Libby, J. Chem. Phys~., 11 951 (1910).

l

.....ao-WJ—‘r‘mo’

_

 

130

18. R. M. Adams, R. B. Bernstein, and J. J. Kata, J. Chem. Phys., 23
1622 (1955).

19. W. H. Johnson and W. F. Libby, 118th National Meeting of the Am.
Chem. Soc., Chicago, Sept., 1950.

20. L. C. Liberatore and B. 0. Wiig, J. Chem. Phys” _8_ 165 (19140).
21. w. r. Libby, J. Chem. Phys., g 31.8 (191.0).
22. L. c. Liberatore and E. 0. wiig, J. Chem. Phys., g 31:9 (1910).

23. n. 1. Gilbert, 1. Roberts, and 2. 1. Griswold, Phys. Rev., 15;
1723 (19b9).

i
'3

21.. n. w. Magnuson , J. Chem. Phys., 23 229 (1952).

25. D. F. anith, The Microwave Spectrum and Structure of Chlorine
Triflmride , Carbide and Carbon Chemical C

empany, New York (1952);
Rue. Sci. Abstracts, 1 65 (1953); J. Chem. Phys., 21 609 (1953).

$
I

“ma; ~. ‘1. imam-“pat‘lfif' ... -'.7
e. If"

26. E. W. washburn, Editor, International Critical Tables, I 102 ,
McGraw-Hill Book Company, Inc. , New York, 1926.

27. E. W. Washburn, Editor, ibid., I 1011.

28. E. w. Washburn, Editor, ibid., !_I_ 75.

29. Linus Pauling, The Nature of the Chemical Bond, Cornell University
Press, New York, 19148.

30. National Bureau of Standards, Selected Values of Chemical Thermo-
dynamic Properties, Series III,195h.

31. Samuel Glasstone, Textbook of Physical Chemistry, 2nd Edition,
D. Van Nostrand Company, Inc., New York, 19146 , Chapter XIII.

32. 1. 1. Frost and R. G. Pearson, Kinetics and Mechanism , John Wiley
and Sons, Inc., New York, 1953.

33. G. Friedlander and J. W. Kennedy, Nuclear and Radiochemistry,

John Wiley and Sons, Inc., New York, 1955; Introduction to Radio-
chemistry, John Wiley and Sons, Inc., New York, 19h9.

31;. N. V. Sidgwick, The Chemical Elements and Their Compounds,
Oxford University Press, London, 1950.

35. G. M. Harris, Trans. Faraday 800.,91 716 (1951).

36. W. J. Moore, Physical Chemistry, Prentice-Hall, Inc ., New York 1955.

 

37.

38.
39.
110.
111.
’42.
’43.
Mi.
1:5.
146.
14?.

118.
1:9 .

131

R. Abegg and Fr. Auerbach, Handbuch der Anorganischen Chemie,
Leipzig, 1913, IV 2 p. 81.

R. 1. Marcus, J. Chem. Phys., .22 1107 (1955) .

J. C. Sternberg, unpublished work.

J. W. Gryder and R. W. Dodson, J. Am. Chem. Soc., 13 2890 (1951).
J. E. Boggs and L. 0. Brockway, J. Am. Chem. Soc., 213111115 (1955).
a. L. Farrar and H. 1. Smith, J. Am. Chem. Soc., 11 11502 (1955).
R. L. Farrar and H. A. Smith, J. Phys. Chem., 2 763 (1955).

H. Fredenhagen and 0. T. Krefft, z. physik. Chem., £131 221 (1929).
O. Ruff and F. Laass, Z. anorg. allgem. Chem., 122 270 (1930).

F. B. Dutton, Private communication.

J. E. Bo gs, E. R. lrtsdalen, and l. R. Brosi, J. Am. Chem. Soc.
_7_'_(_ 6505 (1955) .

1. A. Woolf, J. Chem. Soc. 19514 1.113.

M. Schmeisser and r. L. Ehenhoch, z. angew. Chem. 99. 230 (1951;).

 

-.P

L

 

,. - .7".
1,.

 

 

 

.IL. "
._ r: . ..
a” flu: g
a of“. . . I... o. r ..vd
L|Iz .l..?\ ..lulhl‘

MESS

132

JPPENDIX I

SGPE CQ‘IMENTS ON AN UNKNOWN MATERIAL ENCGJNTERED DURING THE
C(IJ'RSE OF THE PREIJEDING WORK

Introduction

The history of interhalogen and fluorine chemistry is dotted with
examples of unidentified colored materials. Ruff and isoher (9) re-
ported that when hydrogen chloride gas came in contact with fluorine

gas above liquid fluorine, a greenish light was seen and a white floc
settled in the liquid fluorine. Fractionation yielded an orange
colored liquid which boiled between -100° c. and -80° 0., but quantity
limitations prevented identification of the material .

Ruff and Ascher (9) passed a 2:1 mixture of fluorine to chlorine
at h00° C . through a quartz tube containing a fluorite boat filled with
rhodium catalyst. The condensate of this process contained an orange-
red liquid which etched the quarts, accompanied by the formation of
silicon tetrafluoride. The liquid use not identified.

Fredenhagen and Krefft (uh) sparked a mixture of fluorine and
chlorine at room temperature and observed that a yellow flame spread
throughout the mixture accompanied by either a detonation or a 'puff" ,
depending on reacting mixture. In the absence of water, there was no
explosion. .

Ruff and Laass (1:5) reported that in fused quartz, gaseous

chlorine trifluoride (normally colorless) exhibits an orange cast ,

 

 

 

133 '

possibly due to traces of chlorine oxide from a reaction with silicon
dioxide .
While maidng successive purification distillations of hydrogen

fluoride , Button (116) noticed that the first condensate from the shipping

cylinder occasionally was a brick red solid.

In the present case, during the separation of chlorine and chlorine
trifluoride by distillation, samples of gas were analysed by determining
their ultra-violet spectrum. In this investigation, a green color was
occasionally noted in the chlorine trifluoride fraction. This gas had
an absorption maldmtm in the region of 3700 i, a slightly higher wave-
length than the reglon of the maximum in the chlorine spectrum. Little
importame was initially attached to the green material, because it was
necessary to uncouple and recouple the spectral cell to the gas-
handling system for each sample. Although a metal cap was placed on
the system take-off connection, and a cork inserted in the flared tubing
of the cell, traces of water undoubtedly reached the inside of the

tubing. Water would be ezqaected to react with chlorine trifluoride to

form traces of one of the fluorine or chlorine oxides. Chlorine dioxide,

which has about the same visible color properties , has no ultra-violet
absorption peaks at 3600 2, 3700 fl) or 3800 X, the region of maximum
absorption found (Figure 5b) . Woolf (It?) has recently reported the
formation of chloryl fluoride by the reaction 20 BrF, + 12KC10, -
IZCIOCF + 603 + hBrz + 12 KBrF‘. No visible or ultra-violet spectrlnn
is reported, although Woolf notes that chloryl fluoride may have been

produced by Ruff and Krug (12) by tin hydrolysis of chlorine trifluoride.

 

 

 

 

131+

 

.Howmopma excess: Ho admpoonm .am enemam

M :e mammoao>m3

8mm fin g clown 8mm 8mm BR 8mm Bmm Bush ,
. o.o

Koueqdosqv

 

 

 

 

135

However , Schmeisser and Ehenhoch (118) have reported chloryl fluoride
to be colorless in the gaseous state.

Occurrence

Production of the unknown material was not predictable . Small

bits of silver solder, silver solder and flux, nickel screening, and

pieces of copper had no observable effect on the gas production.

It seemed possible that chlorine trifluoride contaminated with
chlorine (or amounting to the same thing, a catalytic effect from sur-

faces resulting from exposure to such a mixture) was responsible for

the phonoasnon. Consequently, a pair of 10 cm. viewing cells (Figure 55)

were made and evacuated for 2h hours without contact with chlorine tri-

fluoride or chlorine. The cells were then treated with chlorine tri—

fluoride (about 100 m. gas pressure) and re-evacuated. Next, 100 m.
of chlorine trifluoride was placed in one cell, and 100 n. of chlorine
in the other. No visible green gas formed in either of these cells
over a two week period. The cells were then evacuated after which 100

III. of chlorine trifluoride was placed in each cell without visible
green material formation.

Generally, exposure of the opened coupling between cell and take-
off to moist air , then recoupling and treatment 14th chlorine trifluoride

produced the material. However, there were instances when this pro-

cedure failed to produce any coloration . Under conditions favorable

for formation, the recoupled cell we treated with 50 m. to 200 m. of

chlorine trifluoride . The green gas was visibly fenced at a rapid rate ,

136

 

HHoo mafinmflm3.oconp0ho:am .mn thMwh

00

 

 

 

 

    

_. Igggg

.mmo use deflfidam
A
4

maouzflaho Hoxofis

   

mfiefia enema 811

«0 3509.33 mflmfipgoufinm em
"Hamo mcwkmfi> .mm mASMHm

137

turning quite intensely green in a matter of ten or fifteen seconds.
This gas could be pumped out, the cell evacuated, then more chlorine
trifluoride expamed into the cell accompanied by more green material
formation. This cycle could be repeated several times; after a number
of cycles, formation was slower, sometimes alloung time for rapid,
semi-quantitative scanning of the absorption spectrum. ls green
material formed, chlorine trifluoride disappeared. For the most
intensely green samples, chlorine trifluoride was absent.

Purity and Physical Properties

Purity of the green gas was in doubt because the gas was either
umtable or very reactive with some constituent of the system. The
process of successively condensing and distilling to purify was not
feasible because the amount of green material decreased uth each dis-
tillation. Furthermore , a sample was condensed once, and amended into
the system consisting of cell, line , and Helicoid gauge. Valves were
then closed isolating the cell and the Helicoid gauge. Spectral curves
of the material in the cell after time t, along with notations of
pressure in the Helicoid gauge at time t are show in Figure 57.

i fluorothene weighing vessel (total weight about 55 We, see
Figure 516) was made for vapor -density molecular weight measurements ,
but use of the apparatus was not warranted because sufficiently pure
material could not be obtained.

In appearance, the material was an intensely green gas which
condensed to a dark chorry-red liquid and solidified as a brick-red solid.

.. n; ..ma 1w s-‘nafl‘. . 9“;
. ~ _ . ‘V
0
ll

‘3"

138

! Y... 131‘: .1; . . I Jamal

.ofia» mo soaponsm o no Howuouoe crosses no aeupooam .um madman

5 sameness:
Bus 68.» 8mm “ms—mm pawn fimn 8mm pmfi Rmm 8H .
_ a _ T a 0.6

\i./
J a
r ...
\a
/

 

J n.0,

 

\\

1| 5 . .. l1 non—H

’/ ‘
Ii o.~

r1 .5

 

..oafia omen» no ousoooam flagshm _
____L_..____..____._oN

 

 

fousqaoeqv

139

Usually the red condensed material was mottled with a slightly yellowish
colored solid, which, by comparison with pure chlorine trifluoride, was
taken to be the trifluoride. This was reasonable because the condensed
material came from the spectral cell, plus system connections, plus
weighing cell itself; the total volulle was thus several times the volmae
of the spectral cell. By asetning this yellowish colored mterial to

be chlorine trifluoride , and by qualitative comparison, the melting
point of the red solid was estimted to be between -100' c. and -80’ c.

Similarly, the boiling point was estimated to be between -2o°c and +5' 0.

Other Work

Using the infrared cell described’in Section IV, and a Perkin-
Elmer Model 21 Spectrophotometer, nmborous attempts. were made to obtain
the infrared spectrum of the material. No evidence of the presence of
materials other than chlorine trifluoride or chlorine monofluoride was
obtained.

‘9‘ 2"”

.... ....--- .. ...

‘e‘

1140

APPENDIX II

ORIGINAL DATA

Chlorine nonoftuorids fonnation data
Chlorine trifluoride and chlorine exchange data

Chlorine trifluoride-chlorine‘monofluoride exchange
data

Chlorine monofluoride-chlorine exchange data
Helicoid gauge calibration data

.9 r"

-‘u".. 111: L. A.

CHLORIDE HONOFLUORIDE FWTICN DATA

 

Pressure Observed on I'0" Gauge (mm.) at 180° 0.

 

Tine
Him. Ffie No. 55 55 573' 53: 567
o hoe We 1:16 hos hlh
l hl6 h3h
2 h18 has hll h19
3 h20 h36
h h21.5 h39 hls h22
5 ha? h23 hhl
6 hh3 h26
7 hzs h21
8 Lb? h30
9 h30
10 L21 h51 h25
ll bah h36
12 hSh
13 1137 1430
In hhl
ls h3l hS9
l7 hhz h37
18 bk?
l9 hhs
20 the h68
22 nus
23 h72 h53
2h h53
25 hb9 h75
27 hSI
28 h65 h59
29 L61 h68
30
33 h58 héh
3h h67.5
37 h79
38
39 h73
hl bah
h3 h67 h7h
hh heo
us use
he L91
So - h85.5 h93
52 h75
5h h89 L9?
57 h99
59 1493 1:80
60 502
66 has
71- 506

 

 

v ressuro obsorvod on KL 5h70 gauge.

\C HLORINE HONOFLUORIDE FORMATION DATA

1b2

 

Time

Pressure Observed on '0" Gauge (mm.) at 220° C.

Min. Figure No. 23 55' ' 5; 25 27 28 29 55 5]

 

O

O‘U‘lt'w

6.5

7.5

10
12
15
18
22

hlé bl? hls hl9

u25 h21 h29
h32 h33 h27 h38
u37 h33 bhh

hhz hh3 h37.5 h52

hh? hh9.5 hh2 b5?

h51.5 hh6 h63

th

h56 h67
h70

h60.5

héh

h67.5

h73

h79

h83

h86

h12
hl9
h26
b32

hh9

h56

37S h21

381 1438

38?

39h h57

boo

huh.5 h72
b78
has

his
L21
h26

b3?

hhS

hSh

h21

h37

hél

h68

CHLORINE HWOFIBORIDE FORQTION DATA

_____ A

I
k

.Pressure Observed on "0" Gauge (mm) at 2’40" 0.

1143

 

 

Time ____ _

Min. Flu—igure NT. leg” 1 ""9. 1 20 21 22
o hzo i428 1111; ms 1:19 205 307
.5 h3h hzh 1.25 1.27 213 318
1 hhz MO 1432 1:31: 1:31: 221 326
1.5 151 um ma hhl tho 227.5 333
2 h61 1:53 M9 M8 M6 232 3140
2.5 1:69 1:59 1:56 1455 h52.5 238 31:?
3 1:77 1:65 1:62 1:605 1:58 2h2 353
3.5 1:83 1:71 h65 L63 2h6 358
h [:90 ms 1:75 1:70 h67 250 36b
h.5 h96 Ml; M2 253 369
5 502 1:81: MS 1177 1:75 256 37h
6 513 1:93 1:95 1182.5 1:82 261 383
7 523 500 503 1487 1:86 267 391
8 531 505 510 M? 1:91 271 398
9 539 515 516 275 hot;
10 SM 52h 522 h92 3196 278 Mo
11 551

12 557 531 283 In?
13 1:93 1:99

lb 566 530 536

15 290 126
16 571 Shl

17 539

18 h9h 500

19 Sh3

20 Shh 295 1:35
22 586

25 551 sus

27 S93

30 55h um
32 300 1.1.2
35 5146

38 555 M3
ho

M 601

1:5

So 556

52 106.5

 

CHLOBINEINONOFLUQRINE FORMATION nullf'

 

I
L

 

 

lhh

 

Pressure (Riserved in ”0" Gauge (1mm)

 

 

:11: Femperature, °C. _ 2&0 - . 213 V A 203
w 0 96 365 322
.5 103 330
1 107 392 333
1.5 110
2 113 1408 338
2.5 116
3 119 t22_ 3&3
3.5 121
h h3h 3h8
5 126 M5 352
6 129 h53
7 h61.5 359
8 135 1:70
9 h76 366
10 139 1:82
12 1:91 375
lb 500
18 1h?
20 513 395
25 519 h06
30 522

* Data at 21.00 c. were not included in rate constant determination
on the basis of statistics; data at 2t5° c. and 203° c. were not
included because of deviation from 2h0° C , and 200° C .

lbs

 

 

an.“ mm no.mm new ~\H M\H , . mmm
me. we me.os nuH a\H n\H . cum
ma. nNH m.sm on ;\H «HxH emu
«H. as ~e.mnH eHN H a mnH
mm. HmN an.ea oHH H «\H meH
NN. com o~.seH emu H N omH
mm. oHN s~.o~H aeH H ~\H oNH
«H. mm nm.mmH 4mm H n ma
6H. «Hm em.ee as H «\H ma
3an
40. «mm H.eo~ «Hm H H as» .o«
sedan
Hm. men e~.eH~ eon H “\H eassHH .om-
. ooa\o . as l . ooo4\o w .541: 11 11 11 it
eaHo eaHo neseeseso eHo eHe sensessso eaHo ensue essence .oe

3.3.304 .ohfinonm gage 33.33. 3.92.95 $59980 \«3 no e59 synagogue

magnum maoag Baggage 2H mega man «a

1116

 

 

Re; 3.8 ad» RH S 86 S 8 eHm QH 8
exam 3.8 88 an on man 8 8 N8 QH 8
89m 3.8 8.8 mm; on 3;. 8 8 e8 QH 8H
88.8 8.8 8.8 EH 3 3m 3 8 SH «\H 8
Ram 28H GE 2. 8 nm 8.8 em 8 fit. «\H 8
3o; 13.8 0.8 mm. 8 SK 8 om m3 m\H 8
03.: 6.3 flee mm.m on 86 on 8 m.3H H mH
38.8 8.8 38 mo.~ 8 8.: 8 8 HHH N 8
H5.m 25H H8 3.». Hm $.m HH 8 98 8 H8
880 86H was 2.: on and on mm «8 m 5H
3.3 8.3 fine HQ; em 2..» 8 mm on; m 3
- Helen. 28: 1
.st.H .st .eee\e eaHo. .eee\e ..HHo .8 .5
>83 «\H s 83.2.38 emHo 8368.80 aHo 838.58 .88. 838880 JG .8482
eoH u m .3833 .3833. 888.5 .3533. .eeeeesn e936 .2888 \ng 8388
as seen misses gasses H38.

I r? r I}
‘Jll K1 1"

‘ 1"! ‘11 ‘III l I! ‘ 1 ‘ ‘1 l1

. o onfim .2 E56 manganese 23388th8 28.5... as. an 558m 8» :3

1147

lb- ’

"1. ..r'. . In, .

.33.? van was owgm and .3230 83.3398 £003on 05..» 23 035009 63» a.“ no»: :02 n.

 

.oom.H o8.mH 8.88 a8.H 8m 8m.0H 8m om 8m8 m\H
848.:H 88.8H 00H 00.0 08 08.88 88 cm gm: H
.88H.8 88.8H 8.88 48.: H8 8o.m8 88 88 om8 H
80mm.o OH.H8 8.48 88.m o: 48.8H o: Hm cm: 8
88.8H 88.8 8.88 8H.H om 88.8 cm 88 88: 8\H mm
8H.8H 0m.HH 8.88 o8.H 84 Ho.8 on om 8m; m\H 8m
88.0H 88.8H n.m8 H8.H no 80.8H e8 0m 88; 8\H 88
mo.aH m8.mH 0.88 mm.8 8o oo.8H 8o om 8m; m\H 88
08.0H mo.HH 8.88 88.8 88 04.8H 8m om Hom m\H Hm
mHH.8 88.HH +OOH 44.8 mm mm.8 om om 888 8\H 8m
048.8 8H.8 8.H8 88.H mm 84.8 mm om mHH 8\H cm
Hom.8 mo.HH 8.88 08.; o; mm.8H o; om 8mH H cm
43% 8.3 Q88 8m.8 88 H84. 88 on MHH 8 mm
o8.0H 88.oH 8.88 H8.m H: 48.8 H: om 888 8 Hm
HH.0H 88.8H +ooH H8.H om o.HH om om Hom m 88
‘88HewH .aHe 888ml .52
\oHoE .oon\o 08:0 .oon\o .56 .aa
cognmvmm «820 39098.80 .50 “83098.30 . 00 03.08.80
OH x m 8\H p haHpHpoH. 8pH>Hpo< .88288888 haH>HpoH .88988888 .8588 .ouaungum ”8H0 888352
0 £30qu mg.“ .8560 m5 98.60 09.56 dance \hHo compommm

“VII

4

.o oa.m:~ .5. Eamwm Managua—6: HEQEEQHMOBEB mun—”moan. 8.3. 2H eczema wow 42

88.8

 

.0 88H.m 88.08 8.88 H8.0 0m 0m 88 484 m\H 4H
M 888.8 84.80 8.88 0m.H 04 88.8 04 on 084 m\H m
880.8 88.04 8.88 80.8 08 m8.HH 0m 0m H88 m\H 8H
HmH. 8 80.88 m. 88 40. 8 04 04. HH 04 08 H8 m\H 4
844.H 88.8m 0.08 mm.H 04 H8.8 04 0m 00H 8\H mH
88m.H 8m.04 8.88 00.8 H4 44.0 H4 88 8.00H 8\H 8H
880.4 08.04 H.m8 08.m 00 4m.mH 00 88 084 8\H 0H
08m.8 88.84 8.88 H8.8 08 48.8 08 88 0H8 8\H 8
884.H H0.mm 4.88 84.m 0m 80.HH 0m 0m H4H H m
0H0.m 88.mm 8.88 80.8 08 08.8H 08 m8 088 H 8
m88.H 84.84 +00H 88.8 Hm 88.m Hm 88 8.00H 8 HH
80m.m 84.H4 +00H 80.0 08 88.8H 0m 88 H84 8 8
H8H.8 88.08 m.88 88.8 88 H0.0 88 08 HH8 8 0
8H8.8. -80.04 .00H. 88.m 88 84.8 88 88 488 m 8
08m.m 04.8m 8.88 04.4 _ 88 88.8 88 88 H84 8 H
.888, a ., ;» 14‘0unw8e. .aa -
.53..." . 000\0 08:0 . 000\0 ..Hno . 00 . as
\0H05 . 8803:0008 0.5.0 0300.300 820 009008.800 . 980a. . 0300.300 -
00H2 8 8\H p mpapHpoH. 88H>HpoH .08880088 haHpngH .88088088 88:00 .08088088 «8H0 . 880242
38.88 33:80 850550 H308 ES 83888

It

It

 

‘1‘111

’
111‘

‘4‘] l‘

o - .

. o 0.... now 91 Eamwm mamonuqhozom maméonmamoamga gmoqmo 8.5. 2H @638 mom <93

‘1‘ 1

lh9

 

888.H 0.80H 8.88 88.88 08 0H.88 08 88 H8H H
-- u. 8.88 0H.40 08 40. 88 08 88 888 H
8H8. 4 8. 88 0. H8 H. 88 08 88.88 08 88 888 H
888.8 0H.88 00H 88.88 08 88.48 08 88 888 H
cam-Hal 5 |! ‘ * Ala! | Us |
.n83 .H .ooj\0 «Ho .001\0 mac .80 .II
\oHoe 830308 H..Ho 0308.80 .88 0308.80 .958 038.800
00H x 8 8\H 0. 880.33 0:584 .23888 38:03 .93888 08.80 .3588 «Hots
20808 85.8500 H308

‘ll‘ 1!! { ‘1' 1'11

85.8080

111'

‘

. 8808188008 8008 .84 888888 8088058080: 88888088988880.8880 888 28 80848088 80.8 «.83

ISO

 

008 888 088
888 088 .848 808 8.808
888 808 4H8 808 8.808
080 880 H80 880 880
888 408 808 488 408 488 088 888
888 8H8 888 888 H08 8H8 H84 484
880 880 840 004 844 084 H88 8.888
888 888 088 888 088 888 0H8 w 888
888 808 088 H88 888 808 088 8.888
888 888 8.488 488 888 448 808 8H8
H8H 88H 8. 88H 88H 48H 08H 08H 88H
88 80 88 0HH 88 00H 08 08
88 8 88 88 8 88 0.0 8H
48. 0 8.8 8 0 8 0 H
$8088 I; L Wacaomr w I I 1 -
0825 8580.008 . a... 085.00 8880008 .3: 8580.008 .85

0800880: 08.03 . . 80.300988 08008808 08:00 . . 80.800088. 088.00 .. . 80.300098
8 o , 183888 . . . -_

 
  

 

 

 

 

 

20H Ramada @023 30 058:

7224761888425

(129331.114? 3 1 ’52?

 

 

 

 

‘ CHEMISTRY LIBRARY
Thesis

c.2 Phelps, J.P.
Study of the kinetics of some
formation and isotope exchange

reactions involving the chlorine
flourides.

 

—-._.___ _____T_..._.4._

. :2 _. - -..—... __ ..- _m_ 183;?R" i‘:':.:?.1.‘=1=' :31".‘: Z '_'.T_‘ 1' '3‘...” .‘41.”‘:.‘ Z" '.

Thesis

c.2 Phelps. J-P.

StuCy of the kinetics of some form—

ation and isotope exchange reactions

inyolving the chlorine flourides.
Ph.D. 1956

 

IIIHMWIH

174 494

I

293 03

31