PERMANGANATE AS A REAGENT FOR THE SEPARATION AND
DETERMINATION OF CESIUM
DISSERTATION
P r e sen te d in P a r t ia l F u lf illm e n t o f t h e Requirem ents
fo r th e Degree Dootor o f P h ilo so p h y i n th e
Graduate S ch o o l o f The Ohio S t a te
U n iv e r s it y
By
WALLACE HENRY DEEBEL, A .B ., Ed.M ., M .So.
******
The Ohio S t a te U n iv e r s it y
1957
Approved bys
A d v iser
Q
Department o f C hem istry
ACKNOWLEDGMENT
The author h ereby e x p r e s s e s h i s s in c e r e a p p r e c ia t io n t o D r. E a rle R.
C aley f o r h i s s u g g e s tin g t h i s i n v e s t i g a t i o n anc, f o r h is a d v io e and
gu idance d u rin g i t s
c o u r se .
ii
TABLE OF CONTENTS
Page
I n tr o d u c tio n .....................................................................................................................
I
M a t e r ia ls ..............................................
5
Experim ents on P r e c i p i t a t i o n o f Cesium Perm anganate....................................11
R e p r e o ip it a t io n o f Cesium P e r m a n g a n a te .............................................................. 20
B ehavior o f Ammonium Permanganate Reagent tow ard
Rubidium C h lo r id e S o lu t io n s .......................................................................
22
B eh avior o f Ammonium Permanganate Reagent toward
P o ta ssiu m C h lo rid e S o lu tio n s
...................................... . . . . . .
25
E xperim ents on P r e c i p i t a t i o n o f Cesium Perm anganate i n t h e
P r e sen ce o f Rubidium...................................................................................
2?
E xperim ents on P r e c i p i t a t i o n o f Cesium Perm anganate i n th e
P r e se n c e o f P o t a s s i u m ...........................
D e te rm in a tio n o f Cesium by a V olum etric Method
SO
...........................53
S t a b i l i t y o f Ammonium Permanganate R e a g e n t .....................................................34
G en eral D is c u s s io n . ............................................... . . . . . . . . . . .
3 7
Recommended P r o c ed u r e ............................................................................................
38
N otes on P r o c e d u r e ....................................
4 0
Summary. . . . . . . . .
.........................
. . . . . . . .
B ib lio g r a p h y .....................................................................................................................
iii
41
4 3
LIST OF TABLES
T a b le
1.
2.
3.
4.
5.
6
.
7.
8
.
9.
10.
11.
12.
13.
Page
S o l u b i l i t y o f th e Perm anganates o f P otassiu m ,
Rubidium , and Cesium a t C e r ta in
Tem peratures . . . .
4
Molar C o n cen tra tio n o f th e A lk a li M etal Io n s in a
Permanganate S o lu tio n a t C e r ta in T em peratures.
. . .
4
A ttem pted R ecovery o f Cesium from C on centrated S o lu tio n s
o f Cesium C h lorid e
..................................................................
12
A ttem pted R ecovery o f Cesium from a S o lu t io n o f Cesium
C h lo r id e i n P r o p io n ic A c i d ...............................................
13
R ecovery o f Cesium from S o lu t io n s o f Cesium C h lorid e
E vaporated t o 1 Drop, D ilu t e d w ith V arious Volumes
o f P ro p io n ic A c id , and P r e c ip it a t e d w ith O ne-anda -H a lf Times th e T h e o r e t ic a l Amount o f Ammonium
P e r m a n g a n a te ...................................................
15
R ecovery o f Cesium from a S o lu t io n o f Cesium C h lorid e
E vaporated t o 1 Drop and T rea ted w ith an E xcess
o f Ammonium Permanganate
........................................................
15
R ecovery o f
17
Cesium P r e c ip it a t e d und er Standard C o n d itio n s
R ecovery o f Cesium from a S o lu t io n o f Cesium C h lo rid e
C o n ta in in g 5 .0 mg. Cesium p e r m l. under Standard
C o n d i t i o n s ..............................................
18
R ecovery o f Cesium from a S o lu t io n o f Cesium C h lo rid e
C o n ta in in g 2 .0 mg. Cesium p er m l. under Standard
C o n d itio n s
. . . . . . . . . . . . . .
19
R eoovery o f Cesium w ith V a rio u s C o n ce n tr a tio n s o f Reagent
under Standard C o n d itio n s ............................................................
20
P r e lim in a r y E xperim ents on B eh a v io r o f Ammonium
Permanganate R eagent tow ard Rubidium . . . . . . . .
23
B eh avior o f R eagents o f Lower C o n c e n tr a tio n toward
R u b id iu m ..................................................................................................
23
P r e lim in a r y Experim ents on B eh avior o f R eagent tow ard
Lower C o n ce n tr a tio n s o f Rubidium
......................................
24
iv
LIST OF TABLES (CON«T)
T able
14.
15.
16.
17.
18.
19.
20.
21 .
22.
Page
B ehavior o f R eagents o f Lower C on cen tration toward
Lower C on cen tration s o f Rubidium.
................... ....
b ehavior o f Ammonium Permanganate Reagent toward
P o ta ssiu m ....................................................................................
.
25
26
B ehavior o f Reagent tow ard Lower C o n cen tration s o f
P o ta ssiu m . . . ................................................... . . . . . . .
Apparent R ecovery o f Cesium from a Standard S o lu t io n
o f Cesium C h lo rid e C on tain in g Rubidium C h lo r id e . .
27
.
28
Apparent R ecovery o f Cesium from a Standard S o lu t io n
o f Cesium C h lo rid e C on taining Sm aller Amounts
o f Rubidium C h lo r id e
. . . . . . . . . .
29
Apparent R ecovery o f Cesium from a Standard S o lu t io n
o f Cesium C h lo r id e C on tain in g Sm aller Amounts
o f Rubidium C h l o r i d e ................................................................. .....
SO
R ecovery o f Cesium from a Standard S o lu t io n o f Cesium
C h lo r id e C o n ta in in g P otassiu m ................................... ............
31
R ecovery o f Cesium from a Standard S o lu t io n o f Cesium
C h lo rid e C o n ta in in g S m aller Amounts o f P o ta ssiu m .
.
32
R ecovery o f Cesium from a C oncentrated S o lu t io n o f
Cesium C h lorid e C on ta in in g Other A lk a li C h lo r id e . .
33
23.
V olu m etric E s tim a tio n o f Cesium
34
24.
S t a b i l i t y o f Ammonium Permanganate S o lu t io n s . . . . . . .
35
25.
Maximum Volumes and M o la r it ie s o f Ammonium Perm anganate
R eagent A llow ed w ith o u t P r e c ip it a t in g One A lk a li
A lon e i n a C h lo rid e S o lu t io n
............................
38
v
. . . . . . . .
PERMANGANATE AS A REAGENT FOR THE SEPARATION AND
DETERMINATION OK CESIUM
INTRODUCTION
B ecause o f th e s i m i l a r i t i e s i n t h e ch em ical b e h a v io r o f t h e i r io n s
and i n th e s o l u b i l i t i e s o f t h e i r s a l t s , th e s e p a r a tio n o f cesium from
rubidium and p otassiu m , or th e d e te r m in a tio n o f cesiu m in th e p resen ce
o f rubidium and p o ta ssiu m , has been found t o be one o f t h e most d i f f i ­
c u l t problem s o f in o r g a n ic ch em ical a n a l y s i s .
I n th e p e r c h lo r a t e , o o b a l t i n i t r i t e , and c h lo r o p la t in a t e methods
f o r p o ta ssiu m , cesium i s p r e c ip it a t e d w ith o u t any s e p a r a tio n ( 7 ) .
Noyes and Bray ( 6 ) have g iv e n d e t a i l s f o r u s in g th e p e r c h lo r a te method
o f group s e p a r a tio n , f o r c o n v e r sio n o f t h e a l k a l i c h lo r id e s t o o o b a l t i n i t r i t e s , and f o r s e p a r a tio n o f cesium and rubidium from p otassiu m
as th e t r i p l e n i t r i t e s .
They s p e c if y t h r e e r e a g e n ts f o r t h e s e p a r a tio n
o f cesiu m from rubidium and f o r i t s d e te r m in a tio n .
F i r s t , antim ony t r i ­
c h lo r id e i s u sed t o p r e c ip i t a t e m ost o f t h e cesiu m , th e n sodium hydro­
t a r t r a t e or sodium 6 -c h lo r o - 5 -n it r o t o lu e n e m e ta s u lf o n a t e t o p r e c ip i t a t e
m ost o f th e rubidium , and f i n a l l y s i l i c o t u n g 3 t i c a c id f o r t h e p r e c ip i ­
t a t i o n o f th e r e l a t i v e l y sm a ll amount o f rem aining c e siu m .
The method
i s tim e-co n su m in g .
O 'Leary and P a p ish ( 7 ) have d e s c r ib e d th e s e p a r a tio n and d eterm in ­
a t io n o f th e th r e e elem en ts by a l s o u s in g t h r e e r e a g e n ts i n s u c c e s s io n .
P r e c i p i t a t i o n w ith 9-phosphom olybdic a c id s e p a r a te s rubidium and cesium
from p o ta s siu m .
S i l i c o t u n g s t i c a c id s e p a r a te s cesium from rubidium .
C h lo r o p la tin ic a c id p r e c ip i t a t e s cesiu m .
A lthough t h e method may be an
improvement o f th e p reced in g m ethod, th e s e p a r a tio n s are not e n t i r e l y
c le a n - c u t ( 3 ) .
A f t e r f in d in g t h a t e x i s t i n g m ethods d id not g iv e s a t i s f a c t o r y r e ­
s u l t s when a p p lie d t o rock s and m in e r a ls , W e lls and S te v e n s (1 0 ) d ev elo p ed
a method f o r th e d e ter m in a tio n o f cesium and th e o th e r a l k a l i e s .
They
noted t h a t la r g e q u a n t it ie s o f r a r e a l k a l i e s had been used by p r e v io u s
i n v e s t i g a t o r s in t h e i r a n a l y t i c a l s t u d i e s , w h ereas t h e s e ele m en ts u s u a lly
occur i n sm a ll q u a n t it ie s in a c tu a l sa m p le s.
The c h lo r o p la t in a t e s o f
p o ta ssiu m , rubidium , and cesium , adiich a r e se p a r a te d from th e o th e r
a l k a l i e s a s a group, are w eigh ed , and c o n v e r te d t o c h lo r id e s .
A fte r
rem oval o f t h e p latin u m by p r e c i p i t a t i o n w ith h o t d i l u t e form ic a c id ,
rubidium and cesium are se p a r a te d from p o ta ssiu m by treatm en t o f t h e s o lu ­
t i o n o f c h lo r id e s w ith g a se o u s hydrogen c h lo r id e and a b s o lu te a lo o h o l
s a tu r a te d w it h th e g a s .
The e x t r a c t o f rubidium and cesium c h lo r id e s
th e n c o n ta in s o n ly 0 .6 mg. o f p o ta ssiu m c h lo r id e .
Rubidium i s p r e o ip it a t e d
a s t h e s u l f a t e from t h i s e x t r a c t b y t h e a d d it io n o f a lc o h o lic ammonium
s u lfa te .
T h is method i s a l s o tim e -c o n su m in g .
H i l l y e r ( 4 ) , i n u s in g t h e method o f W e lls and S te v e n s , has shown
t h a t a s many a s s i x e x t r a c t io n s m y b e n e c e s s a r y , i f t h e sample o o n ta in s
much rubidium or cesium , a s f o r exam ple i n h i s a n a ly s e s o f sam ples o f
p o l l u c i t e ( 9 ) t h a t co n ta in e d over 30 p e r c e n t o f cesiu m o x id e .
th e number o f e x t r a c t io n s , he s u g g e s ts t h r e e p r o c e d u r e s t
a liq u o t p a r t , i f th e r e i s enough p o ta ssiu m t o f u r n is h
c h lo r id e f o r each e x t r a c t io n ,
2
0 .6
1
To reduce
) t o u se an
mg. o f p o ta ssiu m
) i f p o ta ssiu m i s low , t o s u b s t it u t e
f o r t h e a b s o lu te a lo o h o l a m ixture o f c o n c e n tr a te d h y d r o c h lo r io a o id and
a lo o h o l, w hich d i s s o l v e s 3 .1 mg. o f p o ta ssiu m c h lo r id e and about t e n
tim e s as much rubidium c h lo r id e and cesium c h lo r id e as th e a b so lu te
a lc o h o l, or
3) i f p otassiu m i s v ery low , t o omit th e e x t r a c t io n o f
cesium c h lo r id e from th e m ixea c h lo r id e s and t o t r e a t th e c h lo r id e s as
cesium c h lo r id e c o n ta in in g a t r a c e o f p o ta ssiu m c h lo r id e .
A fte r
u s in g any o f th e t h r e e p r o c e d u r e s, rubidium i s se p a r a te d w ith a l c o h o li c
ammonium s u l f a t e , a s d ir e o t e d by W ells and S te v e n s ( 1 0 ) .
H illy e r ’ s
m o d ific a tio n a v o id s an e x o e s s iv e number o f e x t r a c t io n s , but th e method
i s s t i l l tim e-co n su m in g .
W ells and S te v en s (1 1 ) i n a l s o d is c u s s in g t h e a n a ly s is o f a p o l lu e i t e c o n ta in in g a h ig h p e r c en ta g e o f cesiu m o x id e s u g g e ste d th e sep a ra ­
t i o n o f th e b u lk o f th e o h lo r o p la t in a te o f cesium from t h a t o f p o ta ssiu m
and o f rubidium b y s e v e r a l f r a c t i o n a l c r y s t a l l i z a t i o n s , fo llo w e d by
t h e i r ( 1 0 ) procedure f o r s e p a r a tin g cesium from p otassiu m and rubidium
i n th e s o lu b le o h lo r o p la t in a t e s o lu t i o n w ith a l c o h o li c ammonium s u l f a t e .
A lthough t h i s m o d if ic a t io n may s h o r te n t h e method c o n s id e r a b ly , i t i s
s t i l l not r a p id .
T h is p r e s e n t i n v e s t i g a t i o n was und ertaken w ith
v ie w t o d e v e lo p in g
a more rap id method f o r th e s e p a r a tio n o f cesiu m from p o ta ssiu m and
rubidium and f o r i t s d e te r m in a tio n i n t h e i r p r e s e n c e .
A su rv ey o f th o
s o l u b i l i t i e s o f cesium compounds s u g g e s te d t h a t th e s o l u b i l i t y o f cesium
permanganate was low enough f o r q u a n t it a t iv e p r e c ip i t a t i o n o f t h e e le m e n t,
e s p e c i a l l y a t low te m p e r a tu r e s.
P a tte r s o n ( 8 ) g iv e s th e s o l u b i l i t y o f
cesium permanganate in a s a tu r a te d aqueous s o lu t i o n a t 1°C. and a t 19°C.
He a ls o g i v e s th e s o l u b i l i t y o f rubidium permanganate a t 2°C . and a t
1 9 °C ., and o f potassiu m perm anganate a t 0°C .
These d a ta , t o g e t h e r -with
th e s o l u b i l i t y o f p otassiu m perm anganate a t 1 9 .8 °C . as g iv e n by B a x te r ,
B o y lsto n , and Hubbard ( 1 ) , a r e shown in T able 1.
TABLE 1
SOLUBILITY OF THE PERMANGANATES OF POTASSIUM, RUBIDIUM,
AND CESIUM AT CERTAIN TEMPERATURES
°c.
KMn04
Grams
RbMn04
Grams
CsMn04
Grams
0
2 .8 4
••••
• • *•
••••
#• • •
••••
0 .4 6
1 .0 6
••••
0 .0 9 7
•••»
0 .2 3
• • «•
1
2
19
1 9 .8
5.96*
* T h is f ig u r e i s f o r g . p er 100 g . o f s o lu t i o n .
f ig u r e s a r e f o r g . p e r 1 0 0 c c . o f s o lu t io n *
The oth er
O
At 1 C. th e s o l u b i l i t y p rod u ct f o r cesiu m perm anganate i s 1*5 x 10
and t h e m olar c o n c e n tr a tio n o f th e cesiu m io n i n s o lu t i o n i s 3 .9 x 10“3 .
The d a ta o f Table 1 i n term s o f t h e m olar c o n c e n tr a tio n o f t h e a l k a l i
m eta l io n s are shown i n Table 2 .
TABLE 2
MOLAR CONCENTRATION OF THE ALKALI METAL IONS IN A
PERMANGANATE SOLUTION AT CERTAIN TEMPERATURES
C o n c e n tr a tio n i n M oles p er L it e r
°C.
0
1
2
19
19 .8
Rb*
K+
1 .8 0 x IQ -
1
» • • #
• «« •
• • • •
_
3 .7 7 x lO " 1
••••
....
2 .2 5 x 10 " 2
5 .1 8 x 1 0 - 2
••••
Cs+
« •••
3 .8 5 x 10 ~ 5
....
9 .1 5 x io - 3
••••
For t h e s o l u b i l i t i e s a t th e t h r e e lo w e st te m p e r a tu r e s, t h e r a t i o s t o
cesium a r e :
K : Cb * 47 * l j
Rb * Cs * 5 .8 : 1, and th e r a t i o s
a t th e h ig h e r tem p e r a tu re s a r e ;
K i Cb 8 41 i l j
Rb j Cs = 5 .2 : 1.
A lthough t h e s o l u b i l i t y o f cesium permanganate a t 1°C. i s o n ly 0 .9 7
mg.
p er m l. (T a b le 1 ) , t h e p o s s i b i l i t y appeared t h a t i t might s t i l l be low er
o
a t 0 C.
The above r a t i o s , th ough ap p roxim ate, in d io a te d t h a t p o ta ssiu m
or rubidium perm anganate m igh t be h e ld in s o lu t i o n w h ile p r e c ip i t a t i n g
cesium perm anganate.
MATERIALS
CESIUM CHLORIDE.
Cesium c h lo r id e from a com m ercial so u rce was
examined s p e o tr o g r a p h ic a lly and found t o c o n ta in t h e s e e ig h t im p u r it ie s :
Na, K, Rb, Mg, Ca, A l, Cr, and F e .
Four b o t t l e s ^ c o n ta in in g cesiu m
d io h lo r o io d id e were l ik e w is e examined w ith t h e f o llo w in g r e s u l t s :
B o t t le
No.
I m p u r itie s Found
12
Na,
Mg,
A l,
T l,
S i , Sb, Cr,
F e,
Cu, Ag
13
Na,
Mg, Ca,
A l,
T l,
Sb, Cr,
F e,
Cu
14
Na, Rb,
Mg, Ca, S r , A l, T l,
15
Na, Rb,
Mg, Ca,
A l,
T l,
S n, Cr, Mn,F e , H i, Cu
S i , Sn, Cr, Mn,
F e,
Cu
The copper p r e s e n t a s an im p u r ity was p rob ab ly d e r iv e d from t h e c u t t e r s
used t o sharpen t h e e l e c t r o d e s .
A lthough none o f t h e p r e p a r a tio n s had
few er im p u r it ie s th an t h e com m ercial cesium c h lo r id e , th a t o f b o t t l e 13
was s e le c t e d f o r p u r i f i c a t i o n b ecau se o f th e a b sen ce o f p o ta ssiu m .
T-------------------------------------
These were s tu d e n t p r e p a r a tio n s . They were c o n tr ib u te d by
Dr. K. V. Moyer, Departm ent o f C h em istry, The Ohio S t a te U n iv e r s it y .
6
The s e le c t e d l o t was w eigh ed and th e n h eated a t 200°C. f o r 54 hours
in order t o v o l a t i l i z e th e io d in e m on och lorid e.
To con firm t h e alm ost
com plete removal o f io d in e m on o ch lo rid e, th e w eigh t o f th e r e s id u a l
cesium c h lo r id e was compared wi-fa th e c a lc u la t e d w eig h t o f cesium c h lo r id e
based on th e w eigh t o f th e o e s iu s . d ic h lo r o io d id e ta k e n .
was 0 .0 1 8 5 g . or 0 .0 7 /4 .
The d if f e r e n c e
The c o lo r o f th e reagen t had changed from y e llo w
t o w h ite w ith a f e i n t y e llo w c o lo r under th e s u r fa c e .
F o reig n p a r t i c l e s
o f two k in d s , b la c k and r e d d is h , w ere p r e s e n t, which w ere removed m echanio a l l y w ith a p a ir o f t w e e z e r s .
Two more h e a tin g s a t 200°C. fo llo w e d by
w e ig h in g s showed l o s s e s in w e ig h t o f 1 .9 mg. and 1 .6 mg. r e s p e c t i v e l y .
C on version to th e chloride was t h e n c o n sid er e d t o be com p lete.
T h is cesium c h lo r id e was f u r t h e r t r e a t e d t o e lim in a t e o th e r im p u r it ie s .
I t was d is s o lv e d and f i l t e r e d t o remove a sm a ll amount o f in s o lu b le m a tte r ,
whioh appeared t o be s i l i c a and p i e c e s o f g l a s s .
T h is and a l l subsequent
f i l t r a t i o n s f o r p u r i f i c a t i o n were made through c lo s e - g r a in e d q u a n t it a t iv e
f i l t e r p ap er.
On e v a p o r a tin g t h e p a le y e llo w f i l t r a t e t o d r y n e s s , t h e
r e sid u e was m o stly w h it e , b u t p a r t ly y e llo w .
T h is r e s id u e was d is s o lv e d
i n w a te r , th e s o l u t i o n was h e a t e d , h y d r o c h lo r ic a o id was added, and th e
s o lu t i o n was f i l t e r e d .
Ammonium h y d roxid e was added t o t h e f i l t e r e d
s o lu t i o n , which was a g a in f i l t e r e d .
On ev a p o r a tin g t h i s f i l t r a t e t o
d ryn ess th e r e s id u e was s t i l l n o t c o m p le te ly w h ite .
A ceto n e, i n w hich cesium c h lo r id e i s r e l a t i v e l y i n s o lu b le , was u sed
t o make a number o f r e p r e c i p i t a t i o n s .
The p o r tio n s o f p r e c i p i t a t e were
c o l l e c t e d and d r ie d i n a p la tin u m d is h a t 250c C. and th e n h e a te d t o about
490°C . ( 2 ) .
t o 515°C .
The s a l t was p u lv e r iz e d i n a p o r c e la in m ortar and h e a ted
A fte r d i s s o l v i n g th e s a l t , f i l t e r i n g th e s o lu t i o n , e v a p o r a tin g
th o f i l t r a t e t o d r y n e s s , and r e p e a tin g t h i s s e r i e s o f o p e r a tio n s a number
o f t im e s , t h e d r ie d s a l t was a g a in h e a te d , t h i s tim e t o 5 9 0 °C ., i n a
p latin u m d i s h , and cos l e d .
u n d ern eath .
The s a l t was now w h ite w ith some y e llo w
I t was h e a ted t o 670°C ., where f u s io n occurred ( 2 ) .
The
m elt was c o o le d , and upon d i s s o l v i n g the m ass, th e y e llo w c o lo r o f th e
s o lu t i o n showed t h a t th e p reced in g tr e a tm e n ts had l e f t t h e cesium
c h lo r id e s t i l l c o n ta m in a te d .
C on seq u en tly, t h e s o l u t i o n was t r e a t e d w ith hydrogen s u l f i d e f i r s t
i n a c id medium, then, in b a s ic medium, and t h e p r e c ip it a t e d im p u r it ie s
were removed by f i l t r a t i o n .
A f t e r a n o th er trea tm en t w ith hydrogen s u l f i d e
i n b a s ic medium, th e ev a p o r a te d f i l t r a t e gave a n e a r ly w h ite s a l t .
To
remove ca lciu m t h e s o l u t i o n o f th e s a l t was t r e a t e d t w ic e w ith ammonium
o x a l a t e , a c c o r d in g t o th e p rocedure o f K o lth o ff and S a n d e ll ( 5 ) .
Magnesium was removed w ith
th e same a u th o r s ( 5 ) .
8
-h y d r o x y q u in o lin e by u s in g t h e p rocedure of
A f t e r s e v e r a l tr e a tm e n ts w ith
8
-h y d r o x y q u in o lin e ,
t h e s o l u t i o n was b o i le d on an e l e c t r i c h o t p la t e f o r an hour t o remove
th e o r g a n ic i o n s .
A f t e r t h e s o lu t io n was evap orated t o d ry n ess on th e
steam p l a t e , th e s a l t was g e n e r a lly w h ite .
and c o o le d .
I t was h e a ted t o 5 9 5 °C .,
A fte r d is c a r d in g a minor p o r t io n , y e llo w i n c o l o r , th e w h ite
cesium c h lo r id e was p u lv e r iz e d , b o t t l e d , and w eig h ed .
To co n firm t h e
p u r ity o f th e cesiu m c h l o r i d e , q u a l i t a t iv e sp e c tr o g r a p h ic a n a ly s e s were
made, which showed t h a t t h e f o llo w in g fo u r im p u r it ie s w ere s t i l l p r e sen t*
Na, Mg, Ca, and S i .
S i l i c o n was p r e se n t a s a t r a c e and th e o th e r t h r e e
were v e r y l i k e l y i n i n s i g n i f i c a n t and n o n - in t e r f e r in g am ounts.
s o lu t i o n o f cesiu m c h l o r i d e , c o n ta in in g
f i n a l l y made.
1 0 .0
A stan dard
mg. o f cesiu m p er m l. was
RUBIDIUM CHLORIDE.
Rubidium c h lo r id e , o f two l o t numbers, from th e
Bame comm ercial so u r c e a s th e cesium c h lo r id e , was examined s p e c tr o g r a p h ic a lly .
One l o t number c o n ta in e d s i x , and th e o th e r e i g h t , im pu ri­
tie s *
Lot
im p u r it ie s Found
a
Na, K, Mg, Ca, S i ,
Cr
b
Na, K, Mg, Ca, A l, T l, Cr, Ag
The re a g en t of Lot a , h a v in g th e few er i m p u r it ie s , was s e l e c t e d f o r
p u r ific a tio n .
I t was p u r if ie d in e s s e n t i a l l y t h e same way as th e cesium
c h lo r id e , e x c e p t f o r some o m is s io n s , w hich sh o rten ed th e p r o c e s s .
o m issio n s were*
1
) p r e c i p i t a t i o n s i n a c e to n e were n ot made,
f i l t r a t i o n s o f o b serv ed f o r e ig n m atter were needed,
was n o t r e s o r te d t o , and
(th r e e
3) a p la tin u m d is h
More p r e c ip i t a t i o n s
and magnesium w e r e , how ever, made f o r th e rubidium c h lo r id e
and sev en r e s p e c t i v e l y ) th an f o r th e cesium c h lo r id e (tw o and fo u r
r e s p e c tiv e ly ).
fo r u se.
) few er
4 ) t h e h ig h e s t tem p eratu re o f t h e m u ffle f o r
f i n a l h e a tin g t o c o m p lete w h ite n e s s was 500°C. ( 2 ) .
o f ca lciu m
2
The
The p u r i f i e d rubidium c h lo r id e was w eigh ed and b o t t le d
I t s p u r it y was confirm ed s p e c t r o g r a p h ic a lly .
The s p e c tr o g r a p h ic
a n a ly s is showed t h a t t h e same f i n a l im p u r it ie s w ere s t i l l p r e s e n t a s in th e
cesiu m c h lo r id e and i n t h e same t r a c e or n o n - in t e r f e r in g amounts*
It
d id not show t h a t p o ta ssiu m was p r e s e n t , even th ough no a ttem p t had been
made t o remove t h a t im p u r ity .
POTASSIUM CEI<flRTDB.
The p o ta ssiu m c h lo r id e u sed w as M a llin ck ro d t
rea g en t g r a d e .
AMMONIUM PERMANGANATE SOLUTION.
To p r e c ip i t a t e cesium a s th e p er­
m anganate, a r e a g e n t o f ammonium permanganate was s e l e c t e d , i n p r e fe r e n c e
9
t o an a l k a l i perm anganate, so as t o a v o id th e in tr o d u c t io n o f ex tra n eo u s
a lk a lie s .
Barium perm anganate, " C .P .” , and ammonium s u l f a t e , ”R eagen t-
Grade", were u sed to produce th e rea g en t by t h e f o llo w in g r e a c tio n *
(NH4 ) 2 S 0 4 + Ba(Mn04
) 2
— >
2
NH4 Mn0 4 + 3aS04 .
E q u iv a len t amounts o f t h e rea g en t were ta k en i n such q u a n tity t h a t a
g iv e n volume o f t h e r e s u l t i n g ammonium permanganate s o lu t i o n (0 .0 7 5 M)
would correspond t o th e same volume o f cesium c h lo r id e s o lu t io n c o n ta in in g
1 0 .0
mg. o f cesiu m per m l.
However, th e r e s u lt in g s o lu t i o n was somewhat
more d i l u t e ( 0 .0 6 5 M), a p p a r e n tly b ecau se o f a d s o r p tio n o f th e ammonium
permanganate on t h e barium s u l f a t e .
The w eighed ammonium s u l f a t e was
d is s o lv e d and t r a n s f e r r e d q u a n t i t a t i v e l y t o a s e p a r a to r y f u n n e l.
The
w eighed barium perm anganate was d is s o lv e d i n a l i t e r b e a k e r , f i t t e d w ith
a p r o p e lle r - t y p e g l a s s s t i r r e r a tta c h e d t o an e l e c t r i c m otor.
The ammonium
s u l f a t e s o lu t i o n was in tr o d u c e d dropw ise i n t o t h e barium permanganate
s o lu t io n w it h s t i r r i n g ,
T h is r e q u ire d s e v e r a l h o u r s .
A f t e r th o r o u g h ly
r in s in g t h e s e p a r a to r y fu n n e l and g la s s s t i r r e r , t h e r e s u l t i n g ammonium
permanganate s o l u t i o n c o n ta in in g t h e p r e c ip it a t e d barium s u l f a t e was
h ea ted on t h e s te a m p la te f o r more th an
th rou gh a
p o r o s it y .
2 0 0
8
h ou rs.
The s o l u t i o n was f i l t e r e d
-m l. g l a s s c r u c ib le w ith s in t e r e d g l a s s bottom o f medium
A f t e r h e a t in g on th e ste a m p la te f o r about 24 hours more t o
reduce th e volum e, t h e s o lu t i o n was t r a n s f e r r e d t o a
f l a s k , and d i lu t e d t c th e mark.
1 0 0 0
-m l. v o lu m e tr ic
The ammonium perm anganate s o lu t i o n was
sta n d a r d iz e d a g a in s t sodium o x a la te and found t o have a m o la r ity o f 0 .0 6 5 .
T h erefore 1 .1 6 m l. o f t h i s s o lu t i o n was e q u iv a le n t t o 1 .0 0 m l. o f a cesium
c h lo r id e s o lu t i o n c o n ta in in g 1 0 .0 mg. o f cesiu m per m l.
Subsequent
10
s o lu t i o n s o f ammonium permanganate o f h ig h e r m o la r i t i e s were made.
These s o lu t i o n s were d ilu t e d t o prepare s o lu t i o n s o f low er m o la r i t i e s .
A l l t h e s e s o lu t i o n s o f t h e r e a g en t were s to r e d in brown b o t t l e s and
kept i n t h e la b o r a to r y lo c k e r when n ot i n u s e .
PROPIONIC ACID.
The p r o p io n ic a c id used was r e a g e n t g r a d e .
BURETS AND PIPETS.
A 5 -m l. b u ret was " n alooted " by a p p ly in g a
w a t e r - r e p e lle n t c o a tin g o f N a lc o te
th e o u t s id e o f th e stem .
2
t o t h e i n s i d e o f th e b u ret and t o
The b u ret was th en c a li b r a t e d .
L a te r , when
i t was d is c o v e r e d t h a t t h e ammonium perm anganate s o l u t i o n i n th e b u ret
r e a c te d w ith t h e c o a t in g , th e N a lc o te was rem oved.
The c a lib r a t io n s
were th e re u p o n ig n o r e d , s in c e h ig h ly a c c u r a te volum es o f th a t s o lu t i o n
were n ot n e e d e d .
not n a lo o te d .
and 25 m l.
Two more b u r e t s , 25 m l. and 50 m l., were c le a n e d , but
F iv e p ip e t s were n a lo o te d i 1 m l., 2 m l., 5 m l., 10 m l.,
The t h r e e s m a lle s t were c a lib r a t e d .
FILTER MFDT>.
F i l t e r paper c o u ld not be u se d f o r f i l t r a t i o n s ,
s in c e i t r e a c t s w ith perm anganate.
G la ss f i l t e r c r u c ib le s were u sed
i n t h e e a r l i e r e x p e r im e n ts, and g l a s s f i b e r f i l t e r m ats i n Gooch c r u c i­
b l e s w ere u sed t h e r e a f t e r .
2
Trade name f o r a w a ter r e p e lle n t b y The N&lge C o ., R o c h e s te r , N.Y.
EXPERIMENTS ON PRECIPITATION OF CESIUM PERMANGANATE
In th e b e g in n in g , sm a ll volum es o f cesiu m c h lo r id e s o lu t i o n , having
a c o n c e n tr a t io n o f 1 0 .0 mg. o f cesium per m l.,w e r e p la c e d in a f l a s k c o o le d
b,
an i c e b a th , and t i t r a t e d w ith 0 .0 6 b M ammonium permanganate in n e u tr a l
medium, in h y d r o c h lo r ic acid medium, and i n ammonium h y d roxid e medium.
Wo p r e c i p i t a t e o f cesium permanganate was o b ta in e d in any o f t h e s e
e x p e r im e n ts .
Cesium c h lo r id e s o lu t io n s o f h ig h e r c o n c e n tr a t io n were th e n t i t r a t e d
by ad d in g s l i g h t l y more th an th e s t o i c h i m e t r i c volume o f 0 .0 6 5 M ammonium
perm anganate t o t h e s o lu t io n s c o n ta in e d in a f l a s k c o o le d by a s a lt e d i c e
3
b a th . One su ch s o lu t i o n had a volume o f 1 .0 0 m l. and c o n ta in e d 5 0 .0 mg.
o f c e siu m , and a n o th e r had th e same volume and c o n ta in e d 1 0 0 .0 mg.
Though
some cesiu m perm anganate was p r e c ip i t a t e d , th e su p e r n a ta n t l iq u id r e ta in e d
a p u rp le c o lo r up t o and beyond th e e n d - p o in t.
The two m ix tu r e s were
f i l t e r e d th ro u g h w eighed g la s s c r u c ib l e s , and th e p r e c i p i t a t e s were washed
w ith i c e - c o l d w a t e r .
A fte r h e a tin g f o r an hour a t 1 1 5 °C ., t h e c r u c ib le s
c o n ta in in g t h e p r e c i p i t a t e s were c o o le d and w eig h ed .
r e s u lts .
T ab le 3 shows th e
O b v io u sly th e re co v e r y was f a r from q u a n t i t a t i v e .
S in c e p r e c i p i t a t i o n was so in c o m p le te i n w a te r s o l u t i o n s , i t was
d e c id ed t o t r y s o lu t i o n s c o n s is t in g o f m ix tu r e s o f w a te r and o r g a n ic
s o lv e n t s so a s t o reduce th e s o l u b i l i t y o f cesiu m perm anganate.
One
req u irem en t of such s o lv e n t s was t h a t t h e y be m is c ib le w ith w a te r .
A nother was t h a t t h e y not r e a c t w ith perm anganate.
O b v io u sly m ethyl o r
® The tem p eratu re o f th e s o lu t i o n was - 2 .1 ° C ., a s in d ic a t e d by th e
tem p eratu re o f a f l a s k o f w ater i n th e s a lt e d i c e b a th .
11
12
e t h y l a lc o h o l cou ld not be used b eca u se o f th e e a s e w it h which th e y are
o x id iz e d .
Acetone and d ioxan e were t r i e d , but were found t o be u n s u it a b le
f o r th e same r e a so n .
A c e t ic a d d was d e c id e d ly b e t t e r , but u n fo r tu n a te ly
cesium permanganate i s a p p r e c ia b ly s o lu b le in t h i s s o lv e n t .
Of a l l th e
s o lv e n t s t r i e d , p r o p io n ic a c id appeared t o o f f e r th e b e s t p o s s i b i l i t i e s
as a medium fo r p r e c i p i t a t i o n o f cesiu m permanganate and a s a wash l i q u i d .
TABLE 3
ATTEMPTED RECOVERY OF CESIUM FROM CONCENTRATED
SOLUTIONS OF CESIUM CHLORIDE
Cesium
Taken
mg.
CsMn0 4
T h e o r e t ic a l
mg.
CsMn04
Reoovered
mg.
95
50
189
1 0 0
2 1
79
To examine th e s u i t a b i l i t y o f p r o p io n ic a c id a s a medium f o r p r e c i ­
p i t a t i o n , two s o lu t io n s o f cesium c h lo r id e h avin g volum es o f
2 .0 0
m l ., and c o n ta in in g
d ryn ess.
1 0 .0
1 .0 0
m l. and
mg. o f cesiu m p er m l. were evap orated t o
P ro p io n ic a c id , 1 m l. and 2 m l. r e s p e c t i v e l y , was added t o
th e r e s id u e s i and t o th e r e s u l t i n g s o l u t i o n s , c o o le d i n a s a lt e d i c e
b a th , s l i g h t l y more th a n t h e e q u iv a le n t volum es o f 0 .0 6 5 M ammonium
perm anganate were added.
The p r e o ip it a t e s were f i l t e r e d i n t o w eighed
g l a s s f i l t e r c r u c ib l e s , washed w ith p r o p io n ic a c id , d r ie d f o r an hour
a t 1 1 5 °C ., c o o le d , and w e ig h e d .
The r e c o v e r ie s a s shown i n T ab le 4
are an improvement over t h o s e g iv e n i n T able 3 , d e s p it e t h e s m a lle r
amounts ta k e n , but th e y are s t i l l n o t q u a n t i t a t i v e .
13
TABLE 4
ATTUFT ED RECOVERY OF CESI TJK FROM A SOLUTION OF
CES.aiF CHLORIDE 1 14 PROPIONIC ACID
Cesium
Taken
mg.
CsMnO^
CsMn04
T h e o r e tic a l
mg.
Recovered
mg.
Per Cent
Recovered
1 0 .0
1 8 .9
11.0
58
2 0 .0
3 7 .9
2 2 .7
60
The e f f e c t o f v a ry in g th e volume o f p r o p io n ic a c id , w ith r e s p e c t t o
th e volume of cesium c h lo r id e s o lu t i o n ta k e n , was t e s t e d .
Seven d e t e r ­
m in a tio n s on stan dard s o lu t io n s ( 1 0 .0 mg. cesium per m l.) o f cesium
c h lo r id e , v a ry in g in volume from 1 .0 0 m l. t o 5 .0 0 m l., were made, i n
w h ich th e volume o f added p r o p io n ic a c id v a r ie d from a h a l f t o tv /ic e
t h a t o f cesium c h lo r id e s o lu t io n .
To ea ch s o lu t i o n s l i g h t l y more th a n
th e e q u iv a le n t or t h e o r e t i c a l volume o f ammonium permanganate re a g en t
was added.
The p r e c ip it a t e d cesium perm anganate was f i l t e r e d i n t o
4
w eigh ed Gooch c r u c ib le s f i t t e d w ith g l a s s f i b e r f i l t e r mats , washed w ith
p r o p io n ic a c id , d r ied f o r an hour a t 1 1 5 °C ., c o o le d , and w eig h ed .
The
r e c o v e r ie s from th e s e seven d e te r m in a tio n s v a r ie d from 70/i t o 88^6, b ein g
h ig h e r th a n t h o s e o f Table 4, but s t i l l n ot q u a n t it a t iv e .
To stu d y t h e e f f e c t o f th e p r e sen ce o f p r o p io n ic a c id i n an
unevap orated cesium c h lo r id e s o lu t i o n , t h r e e d e te r m in a tio n s were made
u s in g 1 m l., 1 m l., and 2 m l. o f stan dard s o lu t i o n s cesium c h lo r id e , t o
w h ich were added 1 m l., 2 m l., and 2 m l., r e s p e c t i v e l y , o f p r o p io n ic
^
From t h i s p o in t on, a l l permanganate f i l t r a t i o n s were th u s made.
14
a c id , and a a lig h t e x c e s s o f ammonium permanganate r e a g e n t.
e r i e s ranged from 38,4 t o 47/o.
The r e c o v ­
A ls o , f i v e standard cesium c h lo r id e s o lu ­
t i o n s v a r y in g from 1 m l. t o 5 m l. were evap orated t o 1 drop; 0 .5 m l. t o
2 ml. o f p r o p io n ic a c id and a s l i g h t e x c e s s o f ammonium permanganate
were added, and the r e c o v e r ie s ranged from 74$ t o 87$.
None o f t h e s e
r e c o v e r ie s were q u a n t i t a t i v e , but a s sm a lle r volum es o f p r o p io n ic a c id
were u se d , h ig h e r r e c o v e r ie s were u s u a lly o b ta in e d .
S in c e e v a p o r a tio n
t o one drop and a volume o f r e a g en t am ounting t o o n e -a n d -a -h a lf tim e s
t h e t h e o r e t i c a l were found t o g iv e n e a r ly q u a n t it a t iv e r e s u l t s , th e se
two c o n d itio n s were m ain tain ed i n s i x d e te r m in a tio n s .
S m a ller amounts
o f p r o p io n ic a c id th an used b e fo r e were added t o t h e ev a p o ra ted volume
o f standard cesium c h lo r id e s o l u t i o n .
The cesium permanganate p r e c i p i ­
t a t e was washed w ith p r o p io n ic a c id , and d r ie d f o r an hour a t 115°C.
r e s u l t s are g iv e n i n T ab le 5 .
The
I t i s seen t h a t r e c o v e r ie s ( t h e l a s t t h r e e )
a r e h ig h e r f o r sm a lle r volum es o f p r o p io n ic a c id th a n ( t h e f i r s t t h r e e )
f o r la r g e r volu m es.
T h is confirm ed th e p r e c ed in g o b s e r v a tio n and a l s o
in d ic a t e d t h a t p o s s ib ly no p r o p io n ic a c id sh ou ld be added t o t h e s o lu t i o n .
Other exp erim en ts showed t h a t i t s a d d it io n had no a d v a n ta g e.
From t h i s
p o in t on, th e a c id was u sed o n ly a s a wash l i q u i d .
The e f f e c t o f a la r g e r e x c e s s o f ammonium permanganate r e a g e n t was
t e s t e d by u s in g volum es up t o t h r e e tim e s t h e t h e o r e t i c a l .
In t h e s e
exp erim en ts th e stan dard cesiu m c h lo r id e s o lu t io n was e v a p o ra ted t o 1
drop and no p r o p io n ic a c id was added.
The p r e c ip i t a t i o n was c a r r ie d o u t
i n a v e s s e l c o o le d by a s a lt e d i c e b a th .
The cesium permanganate
p r e c ip i t a t e was f i l t e r e d o f f , washed w ith p r o p io n ic a c id , d r ie d f o r
an hour a t 115°C ., c o o le d , and w eig h ed .
The r e c o v e r ie s were n e a r ly
q u a n t it a t iv e a s shown by th e d a ta o f T ab le 6.
15
TABLE b
RECOVERY OB' CESIUM FROL; SOLUTIONS OF CESIUM CHLORIDE EVAPORATED TO 1 DROP,
DILUTED Vi IT I; VARIOUS VOLUMES OF PROPIONIC ACID , AND PR E C IPI1A TE D V .I2 : CNEAND-A-HALF TIMES THE THEORETICAL AMOUNT OF AMMONIUM PERMANGANATE
Cesium
P resen t
mg.
10.0
20.0
5 0 .0
10.0
20.0
5 0 .0
C2ItbCOOH
Added
m l.
0 .5
1.0
2 .5
0.02
0 .0 3
0 .0 3
CsMnOd
Csl'r.04
R
ecovered
T h e o r e t ic a l
mg.
mg.
1 8 .9
3 7 .9
9 4 .7
1 8 .9
3 7 .9
9 4 .7
1 7 .8
3 5 .1
8 9 .4
1 8 .4
3 5 .8
9 1 .3
Per Cent
Recovered
94
93
94
97
95
96
TABLE 6
RECOVERY OF CESIUM FROM A SOLUTION OF CESIUM CHLORIDE EVAPORATED TO
1 DROP AND TREATED WITH AN EXCESS OF AMMONIUM PERMANGANATE
Cesium
P r e sen t
mg.
E q u iv a le n t
Volumes o f
0 .0 6 5 M
NH4i:n04
T h e o r e t ic a l
mg.
10.0
10.0
10.0
20.0
20.0
20.0
50 .0
5 0 .0
5 0 .0
1 .5
2
3
1 .5
2
3
1.2
2
3
1 8 .9
1 8 .9
1 8 .9
3 7 .9
3 7 .9
3 7 .9
9 4 .7
9 4 .7
9 4 .7
CsMn04
CsMn04
R ecovered
mg.
1 8 .9
1 8 .4
1 8 .8
3 6 .3
3 6 .4
3 7 .9
9 0 .6
9 2 .8
9 3 .2
P er Cent
R ecovered
100.0
9 7 .4
9 9 .5
9 5 .3
9 6 .0
100.0
9 5 .6
9 8 .0
9 8 .4
16
Three o th e r d e te r m in a tio n s , i n which the cesium c h lo r id e s o lu t i o n was
evap orated t o d ry n ess b e fo r e th e a d d itio n o f o n e -a n d -a -h a lf tim e s th e
e q u iv a le n t volume o f th e r e a g e n t, gave r e c o v e r ie s o f 96/,= , 36%, and 9?%.
In view o f th e p o s s i b i l i t y th a t c o o lin g o f th e p r o p io n ic a c id wash
l iq u id m ight g iv e s t i l l iiig h e r r e s u l t s , seven d e te r m in a tio n s , w ith th e
p r o p io n ic a c id c o o le d in an i c e b a th , were made.
Four o f t h e s e
d e te r m in a tio n s w ith a volume o f rea g en t o n e -a n d -a -h a lf tim e s th e t h e o r e t i ­
c a l gave r e c o v e r ie s o f 35;■<>, 98%, 97%, and 99/o, and th e o th e r t h r e e w ith
reagen t volum es o f sev en and o n e -h a lf tim e s th e t h e o r e t i c a l gave 96%,
95%, and 98/o.
Inasmuch a s t h e c o o lin g o f th e wash l iq u id appeared t o
improve r e s u l t s , th e f i l t e r c r u c ib le s were a l s o c o o le d over dry i c e i n
a l l subsequent d e te r m in a tio n s .
As a fu r th e r means o f im proving th e r e s u l t s by re d u c in g t h e volume o f
r e a g e n t, a more c o n c e n tr a te d s o lu t i o n o f 0 .3 2 4 M ammonium perm anganate was
p rep ared .
A s e t o f t h r e e d e te r m in a tio n s was made w ith t h i s more concen­
t r a t e d r e a g e n t, and w it h t h e f i l t e r o r u o ib le s and wash l i q u i d o o o le d .
The apparent r e c o v e r ie s amounted t o 110%, 130%, and 151%.
T hese v ery
h ig h r e s u l t s w ere p ro b a b ly due t o c r y s t a l l i z a t i o n o f some o f th e re a g en t
a t th e low tem p eratu re o f p r e c ip i t a t i o n and f i l t r a t i o n .
STANDARD CONDITION'S.
The c o n d itio n s fo r q u a n t it a t iv e p r e c i p i t a t i o n
o f cesiu m , e s t a b lis h e d by t h e p r e c ed in g exp erim en ts may be c a l l e d th e
stan dard c o n d it io n s .
They w ere used in a l l subsequent d e te r m in a tio n s .
These c o n d itio n s a r e j
1.
The cesium c h lo r id e s o lu t i o n was not e v a p o r a te d .
2.
No p r o p io n ic a c id was added t o t h e cesium c h lo r id e s o l u t i o n .
17
3.
The p r e c i p i t a t i o n was done in a v e s s e l c o o le d by a s a lt e d
i c e b a th .
4.
The f i l t e r c r u c ib le s were c o o le d over dry i c e .
5.
The cesium permanganate p r e c ip it a t e wan washed w ith 6 m l.-9 ml.
o f p r o p io n ic a c id , p r e v io u s ly c o o le d in an i c e b a th .
6.
The p r e c ip i t a t e was d r ie d f o r 1 hour a t 1 1 0 °-120°C .
A s e r i e s o f d e te r m in a tio n s on standard cesium c h lo r id e s o lu t io n s
c o n ta in in g 1 0 .0 mg. o f cesium per m l. were made under t h e s e c o n d it io n s .
The r e s u l t s are shown in Table 7.
TABLE 7
RECOVERY OF CESIUM PRECIPITATED UNDER
STANDARD CONDITIONS
E q u iv a le n t
Volumes o f
0 .3 2 4 M
NH4Mn04
1 .5
2
3
5
7
7 .5
9
10
Per Cent Cesium R ecovered From A
G iven Volume Taken
1 .0 0 m l.
2 .0 0 m l.
5 .0 0 m l.
9 8 .4
9 9 .5
, 9 8 .5 ,
f 100.01
I 9 8 .4 J
1 0 0.0
9 8 .9
1 0 1 .6
1 0 5 .3
9 9 .2
9 9 .5
1 0 0 .0
1 0 2 .9
1 0 1 .1
1 0 0 .3
1 0 1 .1
1 0 1 .6
As w i l l be s e e n , th e r e c o v e r y was v ery s a t i s f a c t o r y .
9 9 .3
9 9 .8
9 9 .9
1 0 0 .7
1 0 1 .1
1 0 1 .1
1 0 0 .8
1 0 0 .3
Even th e h ig h e s t
r e s u lt (105 • 3>o) i s o n ly 0 . 5 mg. d i f f e r e n t from t h e 1 0 .0 mg. cesium ta k e n .
A s e t o f d e te r m in a tio n s on cesium c h lo r id e s o lu t i o n s c o n ta in in g
5 .0
mg. cesiu m p er m l. were th en made, w ith th e volum es o f reagen t s im ila r
18
t o t h o s e used in th e p reced in g s e t o f e x p e r im e n ts .
As shown in Table 8,
th e r e s u l t s were e s s e n t i a l l y q u a n t i t a t i v e .
TABLE 8
RECOVERY OF CESIUM FROM A SOLUTION OF CESIUM CHLORIDE CONTAINING
5 .0 mg. CESIUM PER m l. UNDER STANDARD CONDITIONS
E q u ivalen t
Volumes o f
0 .3 2 4 M
NH4Mn04
2
3
5
7
9
10
pg,j* Cent ,£esium R ecovered From A
G iven Volume Taken
1 .0 0 m l.
2 .0 0 m l.
5 .0 0 m l.
9 1 .6
9 6 .8
9 6 .8
1 0 1 .1
9 8 .9
1 0 1 .1
9 8 .9
9 7 .9
9 5 .8
1 0 2 .1
1 0 0 .0
1 0 0 .5
9 8 .5
9 8 .9
9 7 .9
100.8
9 9 .8
9 9 .6
To a s c e r t a in th e low er l im it o f c o n c e n tr a t io n o f cesium f o r q u a n ti­
t a t i v e p r e c i p i t a t i o n , d e te r m in a tio n s were made on s o lu t io n s c o n ta in in g
o n ly 2 .0 mg. cesium p er m l. w ith volum es o f r e a g e n t a s in Table 8 and
w ith some la r g e r volum es.
The r e s u l t s are shown i n Table 9 .
I t w i l l be
se e n t h a t th e r e c o v e r ie s were not q u a n t i t a t i v e .
I t w i l l be se en from T ab les 6 , 7,
8 , and 9 t h a t cesiu m can be
p r e c ip i t a t e d q u a n t it a t iv e ly from cesiu m c h lo r id e s o lu t io n s having concen­
t r a t i o n s o f 10 mg. o f cesium per m l. and 5 mg. cesium per m l., but not
from s o lu t i o n s having a c o n c e n tr a tio n as low a s 2 mg. cesium per m l.
The lo w er l i m i t i s t h e r e f o r e somewhere betw een t h e l a s t two c o n c e n tr a t io n s .
However, by e v a p o r a tin g s o lu t io n s o f low er c o n c e n tr a tio n th a n 5 mg. o f
cesiu m per m l., q u a n tita t iv e p r e c i p i t a t i o n s can be o b ta in e d .
19
TABLE 9
RECOVERY OF CESIUM FROM A SOLUTION OF CESIUM CHLORIDE
CONTAINING 2 .0 my. CESIUM PER m l. UNDER
STANDARD CONDITIONS
E q u iv a len t
Volumes o f
0 .3 2 4 M
2«4Mn04
Per Cent Cesium Recovered from A
Given Volume Taken
1 .0 0 m l.
2 .0 0 m l.
5 .0 0 ml.
1 3 .2
2 1 .1
5 2 .6
7 6 .3
9 2 .1
9 2 .1
7 1 .1
8 9 .5
1 5 .8
2 3 .7
8 6 .8
7 2 .4
9 3 .4
9 2 .1
6 0 .5
8 6 .8
3 4 .9
5 7 .7
8 2 .5
9 2 .1
9 4 .2
8 8 .4
9 2 .1
9 7 .4
2
5
7
9
10
10
14
16
V arious c o n c e n tr a tio n s o f ammonium perm anganate rea g en t were used
i n making a d d it io n a l d e te r m in a tio n s on 1 .0 0 m l. volum es o f stan dard cesium
c h lo r id e s o lu t i o n c o n ta in in g 1 0 .0 mg. o f cesiu m .
d e te r m in a tio n s are assem b led i n T able 1 0 .
The r e s u l t s o f t h e s e
The two h ig h e s t r e s u l t s i n
Table 1 0 , 1 0 .5 mg. and 1 0 .5 m g., o c c u r r in g a t t h r e e tim e s t h e e q u iv a le n t
volume and a t m o la r it ie s o f 0 .3 2 7 and 0 .2 7 1 are p rob ab ly due t o t h e f a c t
th a t th e y were o b ta in ed i n t h e two ex p erim en ts i n w hich a re a g en t o f h ig h
c o n c e n tr a tio n was r e f r ig e r a t e d .
At t h e s e h ig h
c o ld re a g en t may have c r y s t a l l i z e d w ith cesium
c o n c e n tr a tio n s some o f
th e
perm anganate. That t h i s
i s th e c o r r e c t e x p la n a tio n i s in d ic a t e d by th e f a c t t h a t p a r t i c l e s o f
s o l i d remained on th e s id e s o f t h e r e a g e n t b o t t l e a f t e r f i l t r a t i o n o f
th e rea g en t o f 0 .2 7 1 m o la r ity .
was r in s e d .
These p a r t i c l e s d is s o lv e d when t h e b o t t l e
Except f o r th e h ig h e s t r e s u l t and
th e r e c o v e r ie s were s a t i s f a c t o r y .
th e fou r low r e s u l t s ,
20
TABLE 10
RECOVERY OF CESIUM WITH VARIOUS CONCENTRATIONS
OF REAGENT UNDER STANDARD CONDITIONS
NH4 Ma0 4
M olarity
0 .1 8 1
0 .1 5 9
0 .0 7 S
0 .5 1 7
0 .1 5 9
0 .0 7 6
0 .0 7 3
0 .0 5 4
0 .3 2 7
0 .2 7 1
0 .1 6 3
0 .1 6 3
0 .0 7 3
0 .0 5 4
0 .0 5 4
0 .1 6 3
0 .0 7 3
0 .0 6 9
0 .0 5 4
0 .1 6 3
0 .0 7 3
0 .0 5 4
0 .1 6 3
0 .0 7 3
0 .0 5 4
NH^MnO^
E q u iv a le n ts
1 .5
1 .5
1 .5
2 . 1
2
2
2
2
3
3
3
3
3
3
3
5
5
5
5
7
7
7
9
9
9
Cesium
Recovered
mg.
9 .8
9 .8
9 .6
9 .8
9 .8
9 .4
9 .7
9 .5
1 0 .5
1 0 .3
1 0 . 2
1 0 . 1
9 .7
9 .8
9 .9
1 0 . 2
1 0 . 0
9 .9
9 .7
1 0 . 2
9 .9
9 .5
1 0 . 1
9 .8
9 .5
REPRECIPITATI05 OF CESIUM PERMANGANATE
The p o s s i b i l i t y o f r e p r e c i p it a t in g th e oesium permanganate was
in v e s t i g a t e d .
Water a t room tem p era tu re was t r i e d and found t o d i s s o l v e
v e r y l i t t l e o f th e p r e c i p i t a t e .
Even h o t w a ter had l i t t l e e f f e c t .
S in c e
e a r l i e r exp erim en ts had shown t h a t a c e to n e d is s o lv e d oesium perm anganate
21
t o some e x t e n t , t h a t s o lv e n t was t r i e d on a r eco v ered p r e o ip it a t e .
The
a c e to n e di s s c lv e d some o f th e p r e c i p i t a t e , as was shown by th e d e v e lo p ­
ment o f a deep perm anganate c o lo r , but most o f th e p r e c ip i t a t e remained
u n d is s o lv e d .
A cetone t h e r e f o r e d id not appear t o be s u i t a b l e .
On
t r y in g o x a l ic a c id , i t was found th a t th e permanganate could be r e a d ily
reduced and brought i n t o s o l u t i o n .
However, b ecau se o f th e exten d ed tim e
o f h e a tin g r e q u ir e d f o r t h e d e s t r u c t io n o f e x c e s s o x a la te io n i n th e
s o lu t io n and b e c a u se i t s d e s t r u c t io n by hydrogen p e r o x id e was in c o m p le te ,
th e u se o f o x a l ic a c id f o r r e d u c tio n was abandoned.
S in c e h y d r o c h lo r ic
a c id d i s s o l v e s cesiu m perm anganate and red u ces th e permanganate t o Mn
,
t h a t re a g en t was t r i e d q u a l i t a t i v e l y on a p r e c ip i t a t e o f cesium perman­
g a n a te .
Some h y d r o c h lo r ic a c id and a few drops o f w a ter were added t o
th e p r e c ip i t a t e and t h e r e s u l t i n g s o lu t io n was ev a p o ra ted t o d r y n e s s .
The d r ie d r e s id u e c o n t a in in g manganous io n was d is s o lv e d in a few drops
o f w a te r .
To o x id iz e t h e d iv a le n t manganese io n t o t h e q u a d r iv a le n t
s t a t e and t o remove i t by p r e c i p i t a t i o n , ammonium perm anganate s o lu t io n
was added.
Enough r e a g e n t was added t o g iv e a p e r c e p t ib le permanganate
c o lo r t o t h e su p e r n a ta n t l i q u i d , i n d ic a t in g t h a t
io n had been o x id iz e d .
w a te r .
a ll
th e manganous
The p r e c ip i t a t e was f i l t e r e d o f f , and washed w ith
The w ash in g was c o n tin u e d u n t i l th e w a ter i n t h e stem o f th e
f i l t e r fu n n e l was c o l o r l e s s .
Ammonium permanganate r e a g e n t was added
t o th e f i l t r a t e , and t h e p r e c ip i t a t e d cesium perm anganate was f i l t e r e d
o f f and washed w it h p r o p io n ic a c id .
S e v e r a l q u a n t it a t iv e d e te r m in a tio n s were s im i la r ly made on cesium
c h lo r in e s o l u t i o n s , and on cesium c h lo r id e s o lu t io n s c o n t a in in g rubidium
c h lo r id e .
The r e s u l t s were v a r ia b le .
Some d i f f i c u l t y was e x p e r ie n c e d i n
22
making a q u a n t i t a t i v e t r a n s f e r o f th e r e p r e c i p i t a t e t o t h e f i l t e r , s in c e
a brown p r e c i p i t a t e p e r s i s t e n t l y clung t o t h e w a l l s o f t h e p r e c i p i t a t i n g
v e sse l.
Because o f th e v a r i a b l e r e s u l t s , t h e l e n g t h o f tim e in v o lv e d ,
and t h e d i f f i c u l t y o f t r a n s f e r r i n g th e r e p r e o i p i t a t e , t h e p o s s i b i l i t y of
r e p r e o i p i t a t i o n was not i n v e s t i g a t e d f u r t h e r .
BEHAVIOR OF AMMONIUM PERMANGANATE REAGENT
TOWARD RUBIDIUM CHLORIDE SOLUTIONS
To le a r n t h e b e h a v io r o f ammonium perm anganate tow ard rubidium
c h lo r id e s o l u t i o n s , exp erim en ts were t r i e d w ith v a r io u s volum es o f th e
re a g en t u nd er t h e stan d ard c o n d itio n s s t a t e d p r e v io u s l y .
A s e r ie s of
ex p e r im en ts w ere f i r s t made on 5 .0 mg. o f rubidium a s i t s c h lo r id e i n
1 .0 0 m l. o f w a t e r .
The r e s u l t s are shown i n T ab le 1 1 .
The d a ta i n
t h e t a b l e i n d i c a t e t h a t a l l e x c ep t th e f i r s t volume o f th e 0 .3 2 4 M
r e a g e n t, t w ic e t h e t h e o r e t i c a l , p r e c i p i t a t e s t o o much ru bidium f o r
d e te r m in a tio n s o f cesiu m i n th e p r e sen ce o f ru b id iu m .
A d d it io n a l e x p erim en ts w ith 5 .0 mg. o f rubidium a s i t s c h lo r id e
were made w it h v a r io u s low er c o n c e n tr a tio n s o f r e a g e n t.
t h e s e e x p e r im e n ts a r e shown i n T able 12.
The r e s u l t s o f
I t w i l l b e se en t h a t a p p r e c ia b le
amounts o f rubidium w ere p r e c ip it a t e d under t h e c o n d it io n s o f t h r e e o f
th e e x p e r im e n ts .
23
TABLE 11
PRELIMINARY EXPERIMENTS ON BEHAVIOR OF AMMONIUM
PERMANGANATE REAGENT TOWARD RUBIDIUM
E q u iv a le n t Volumes o f RbMn04
0 .3 2 4 M HH4 Mn04
T h e o r e tic a l
mg.
RbMnO*
R e s u lts C al­
P r e c ip it a t e d c u la te d a s Rb
mg.
mg.
1 2 . 0
0 .7
1 2 . 0
1 . 6
1 2 . 0
1 2 . 0
4 .8
7 .2
7 .7
15
1 2 . 0
8 . 6
2 0
1 2 . 0
9 .1
2
3
5
7
1 2 . 0
1 0
0 .3
0 .7
2 . 0
3 .0
3 .2
3*6
3 .8
TABLE 12
BEHAVIOR OF REAGENTS OF LOWER CONCENTRATION
TOWARD RUBIDIUM
NE4 Xn0 4
M o la r ity
NH4 Mn04
E q u iv a len t
Volumes
0 .0 7 2
0*163
0 .0 7 2
0 .0 7 2
0 .1 6 3
0 .0 7 2
0 .0 7 2
0 .3 2 4
0 .1 6 3
0.072
n
€*
0 . 1
2 . 6
0 . 1
0 .0 4
0 .0 4
2 . 6
0 . 0
0 . 0
0 . 0
0 . 0
3 .8
6 .4
6 .4
7 .8
10
1 1 .5
1 1 .5
RbMn04
P r e c ip it a t e d
mg.
R e s u lts
C a lc u la te d a s Rb
mg.
4 .3
1 . 8
0 . 0
0 . 0
0 . 2
0 . 1
7 .7
8 .7
3 .2
3 .3
0 . 2
0 . 1
24
I f a s m a lle r amount o f rubidium ( 3 .0 m g.) i s u se d , a la r g e r volume
o f re a g en t or a reagen t o f h ig h e r c o n c e n tr a t io n may be u se d .
T able 13
shows t h a t a t l e a s t n in e tim e s th e e q u iv a le n t volume ca u ses no s i g n i f i ­
can t p r e c i p i t a t i o n , and some o f th e r e s u l t s o b ta in ed w ith h ig h e r propor­
t i o n s o f r e a g e n t are s t i l l s a t i s f a c t o r y .
TABLE 13
PRELIMINARY EXPERIMENTS ON BEHAVIOR OF REAGENT TOWARD
LOWER CONCENTRATIONS OF RUBIDIUM
E q u iv a le n t Volumes o f
RbMn0 4
T h e o r e tic a l
0 .3 2 4 M NH4 Mn04
mg.
2
3
5
7
9
1 0
10
15
2 0
2 0
7 .3
7 .3
7 .3
7 .3
7 .3
7 .3
7 .3
7 .3
7 .3
7 .3
RbMn04
P r e o ip it a t e d
mg.
0 . 2
0 . 1
0 .3
0 .3
0 .3
3 .9
0 . 0
0 .5
3 .1
1 . 2
R e s u lts
C a lc u la te d a s Rb
mg.
0 .0 8
0 .0 4
0 . 1
0 . 1
0 . 1
1 . 6
0 . 0
0 . 2
1 .3
0 .5
A d d itio n a l exp erim en ts on 3 .0 mg. o f rubidium as i t s c h lo r id e were
made w ith v a r io u s low er c o n c e n tr a tio n s o f r e a g e n t.
ex p erim en ts are assem b led i n T ab le 1 4 .
The r e s u l t s o f t h e s e
I t w i l l be s e e n t h a t i n s i x o f
t h e exp erim en ts t o o much rubidium i s p r e c i p i t a t e d .
25
TABLE 14
BEHAVIOR OF REAGENTS OF LOWER CONCENTRATION TOWARD
LOWER CONCENTRATIONS OF RUBIDIUM
NH4 ttn04
NH4 Mn0
M o la rity
0 .5 1 7
0 .3 0 3
0 .2 3 5
0 .1 8 1
0 .1 5 9
0 .0 7 6
0 .1 5 9
0 .0 7 3
0 .5 1 7
0 .2 7 1
0 .0 7 3
0 .3 3 5
0 .1 4 8
0 .0 9 5
0 .0 7 3
0 .1 6 3
0 .0 9 6
0 .0 7 3
0 .1 6 3
0 .0 7 3
4
E q u iv a le n t Volumes
3
3 .2
3 .2
3 .2
3 .2
3 .2
4 .2
4 .2
4 .3
6 .3
6 .3
1 0 .5
1 0 .5
1 0 .5
1 0 .5
1 4 .8
1 4 .8
1 4 .8
1 8 .9
1 8 .9
RbMn0 4
P r e c ip ita t e d
mg.
R e s u lts
C a lc u la te d a s Rb
mg.
4 .3
2 .7
1 .5
0 . 6
0 . 2
0 .0 8
1 . 8
1 . 1
0 . 0
0 . 0
0 . 0
0 . 0
0 . 1
0 .0 4
0 . 0
0 . 0
5 .0
1 .4
0 . 6
0 . 0
0 . 0
2 . 1
7 .9
3 .2
0 . 0
0 . 0
0 . 0
0 . 0
0 . 2
0 .0 8
0 . 0
0 . 0
0 . 0
0 . 0
0 . 0
0 . 0
0 . 0
0 . 0
0 . 2
0 .0 8
BEHAVIOR OF AMMONIUM PERMANGANATE REAGENT TOWARD
POTASSIUM CHLORIDE SOLUTIONS
To le a r n th e b e h a v io r o f ammonium permanganate r e a g en t tow ard p o ta ssiu m ,
e x o e rim e n ts were made on c h lo r id e s o l u t i o n s c o n ta in in g 5 0 .0 mg. and 1 0 .0 mg.
o f p o ta ssiu m w ith v a r io u s volum es and c o n c e n tr a tio n s o f r e a g e n t.
r e s u l t s f o r 5 0 .0 mg. o f p o ta ssiu m a r e g iv e n i n Table 1 5 .
The
I t w i l l be s e e n
t h a t p r e c ip i t a t i o n occurred o n ly under th e c o n d itio n s o f th e l a s t t h r e e
e x p e r im e n ts .
26
TABLE 15
BEHAVIOR OP AMMONIUM PERMANGANATE REAGENT
TOWARD POTASSIUM
NH4 Mn0 4
NH4 Mn04
KMn04
M o la r ity
E q u iv a le n t Volumes
P r e c ip it a t e d
mg.
0 .1 6 3
0 .0 5 4
0 .0 5 4
0 .1 6 3
0 .0 5 4
0 .1 6 3
0 .0 5 4
0 .3 2 4
0 .3 2 4
0 .3 2 4
R e s u lts
C a lc u la te d as
P otassiu m
mg*
0 . 1 2
0 . 0
0 . 0
0 . 1 2
0 . 0
0 . 0
0 . 0
0 . 0
0 .1 8
0 .2 9
0 .2 9
0 .5 3
0 .5 3
0 . 0
0 . 0
0 . 0
0 . 0
0 . 0
0 . 0
0 . 0
0 . 0
2
1 9 .0
2 .7
4 .7
0 .7
3
1 . 0
0 . 2
1
I t i s i n t e r e s t i n g t o n o te t h a t th e w e ig h ts o f th e t h r e e p r e c i p i t a t e s
d e c r e a se a s t h e volum es o f t h e 0 .3 2 4 M r e a g e n t in c r e a s e , u n d oubtedly
due t o th e in c r e a s e i n t o t a l volume o f s o lu t i o n .
I f a s m a lle r amount o f p o ta ssiu m i s p r e s e n t, a la r g e r volum e o f
rea g en t or a r e a g e n t o f h ig h e r c o n c e n tr a tio n may be u s e d .
exp erim en ts on 1 0 .0 mg. o f p o ta ssiu m a r e shown i n T able 1 6 .
The r e s u l t s o f
The t a b le
shows t h a t an a p p r e c ia b le amount o f p o ta ssiu m was p r e c ip i t a t e d i n o n ly
one ex p erim en t.
27
TABLE 16
BEHAVIOR OF REAGEKT TCWARD LOT/ER CONCENTRATIONS
OF POTASSIUM
NH4Mn04
NH4Mn04
M o la r ity
KMn04
E q u iv a le n t Volumes
P recip ita ted
mg.
0 .5 9
0 .5 9
0 .8 8
1
1.42
1 .4 7
1 .4 7
1 .4 7
1 .4 7
1 .4 7
1 .4 7
2 .0 5
2 .6
2 .9
5
0 .0
0 .0
0 .1
0 .1
0 .0
0 .1
0 .0
0 .0
0 .2
0 .1
0 .1
0 .0
0 .0
0 .3
2 .4
0 .1 6 3
o.oai
0 .0 8 1
0 .3 2 4
0 .0 7 8
0 .3 3 5
0 .1 4 8
0 .0 9 5
0 .0 8 1
0 .0 7 8
0 .0 7 7
0 .0 9 6
0 .1 6 5
0 .3 2 4
0.3 2 4
R esu lts
C a lc u la te d as
Potassium
m6- \
0 .0
0 .0
0 .0 2
0 .0 2
0 .0
0 .0 2
0 .0
0 .0
0 .0 4
0 .0 2
0 .0 2
0 .0
0 .0
0 .0 7
0 .6
EXPERIMENTS OH PRECIPITATION OF CESIUM PERMANGANATE
IN THE PRESENCE OF RUBIDIUM
W ith a n ew ly-p rep ared r e a g e n t, d ilu t e d t o v a r ic u s c o n c e n tr a t io n s ,
d e te r m in a tio n s on stan d ard s o lu t io n s o f cesiu m c h lo r id e c o n ta in in g rubidium
c h lo r id e w ere made.
Table 17 shows th e apparent r e c o v e r y o f cesium and th e
co rresp o n d in g p r e c i p i t a t i o n o f rubidium from
1 . 0 0
m l. o f a stan dard s o lu t io n
o f cesium c h l o r i d e , c o n ta in in g 5 .0 mg. o f rubidium a s xhe c h lo r id e .
O b viou sly rubidium was p r e c ip it a t e d a lo n g w ith t h e cesiu m i n a l l t h e s e
e x p e r im e n ts, though i n t h r e e o f them th e amount o f c c —p r e c i p i t a t i o n was
a p p a r e n tly very' s m a ll.
28
TABLE 17
APPARENT RECOVERY OF CESIUM FROM A STANDARD SOLUTION
OF CESIUM CHLORIDE CONTAINING RUBIDIUM CHLORIDE
NH^MnO^
M o la r ity
NH4 Mn04
E q u iv a len t
Volumes
f o r Cesium
NH4 Mn0 4
E q u iv a len t
Volumes
f o r Rubidium
Apparent
Cesium
R ecovered
mg.
RbMn0 4
P robably
P r e c ip it a t e d
mg.
RbMn0 4
C a lc u la te d
a s Rubidium
mg.
0 .0 7 2
1 .5
1 .9
1 0 . 2
0 .4
0 . 2
0 .0 7 2
0 .0 5 4
2
2 . 6
1 0 .9
2 . 6
1 0 . 2
1 .7
0 .4
0 .7
2
0 .0 7 2
0 .0 5 4
3
3
WWW
1 1 .5
2 .9
1 . 2
3 .9
1 0 . 6
1 . 2
0 .5
0 .0 7 2
0 .0 7 0
0 .0 5 4
5
5
5
6 .4
6 .4
6 .4
1 0 .9
1 1 .3
1 0 .7
1 .7
2 .4
1 .4
0 . 6
0 .0 7 2
0 .0 5 4
7
7
9 .0
9 .0
1 1 . 0
1 . 8
0 . 8
1 0 .5
1 . 0
0 .4
0 .0 7 2
0 .0 5 4
9
9
Q
1 1 . 6
1 1 .3
1 1 . 6
1 0 . 2
2 .5
0 .4
0 . 2
0 .7
1 . 0
1 . 0
0 . 2
T a b le s 18 and 19 show t h e ap p aren t r e c o v e r y o f cesium and th e oorre^
spending p r e c ip i t a t i o n o f rubidium from
1 . 0 0
m l. o f a stan d ard s o lu t i o n o f
cesium c h lo r id e , c o n ta in in g 3 .0 mg. o f rubidium as t h e c h lo r id e .
It w ill
be s e e n t h a t more rubidium i s p r e c ip i t a t e d w ith r e a g e n ts o f h ig h e r
m o la r i t i e s th a n w ith t h o s e o f low er m o l a r i t i e s .
I n most o f t h e d eterm in a­
t i o n s a t t h e h ig h e r m o la r i t i e s t h e amount o f rubidium p r e c ip i t a t e d i s more
th a n 0 .4 m g.; i n most o f t h o s e a t low er m o la r i t i e s i t i s l e s s th an 0 .4 mg.
29
TABLE 18
APPARENT RECOVERY OF CESIUM FROM A STANDARD SOLUTION OF CESIUM
CHLORIDE CONTAINING SMALLER AMOUNTS OF RUBIDIUM CHLORIDE
NH4 Mn04
M o la r ity
NH4 Mn0
4
E q u ivalen t
Volumes
f o r Cesium
NH4 Mn0
4
E q u iv a len t
Volumes
f o r Rubidium
RbMn04
RbMn04
Probably C a lc u la te d
P r e c ip it a t e d as Rubidium
mg.
mg.
0 .1 5 9
0 .1 5 9
1 .5
1 .5
0 .1 6 3
0 .1 5 9
2
4 .2
4 .2
0 .3 2 7
0 .2 7 1
0 .0 9 5
3
3
3
6 .3
6 .3
6 .3
0 .1 6 3
0 .0 9 5
5
5
1 0 .5
1 0 .5
1 2 . 6
5 .0
2 . 1
1 0 .9
1 . 6
0 .7
0 .0 9 5
7
1 4 .7
1 1 . 0
1 . 8
0 .7
0 .1 6 3
0 .0 9 5
9
9
19
19
1 2 .9
5 .4
2 . 2
1 0 . 6
1 . 2
0 .4
2
3 .2
3 .2
Apparent
Cesium
R ecovered
me.
1 0 . 6
1 . 2
1 0 .5
0 .9
0 .4
0 .4
1 1 . 2
2 . 2
0 .9
1 1 .5
2 .9
1 . 2
1 3 .1
1 3 .2
6 . 1
2 .4
2 .5
1 0 . 8
1 .5
0 . 6
5 .9
30
TABLE 19
APPARENT RECOVERY OF CESIUM FROM A STANDARD SOLUTION OF CESIUM
CHLORIDE CONTAINING SMALLER AMOUNTS OF RUBIDIUM CHLORIDE
NE4 Mn04
Molarity
NH4 Mn04
E q u ivalen t
Volumes
fo r Cesium
NH4 Mn04
E q u iv a len t
Volumes
f o r Rubidium
Apparent
Cesium
R ecovered
mg.
3 .2
0 .0 7 6
1 .5
0 .0 7 3
0 .0 5 4
2
4 .2
4 .2
0 .0 7 3
0 .0 6 9
0 .0 5 4
3
3
3
0 .0 7 3
0 .0 7 0
0 .0 6 9
0 .0 6 9
0 .0 5 4
RbMn04
Probably
P r e c ip ita t e d
mg.
RbMnC' 4
C a lc u la te d
as Rubidium
mg.
0 .3
0 . 1
1 0 . 0
0 . 0
0 . 0
9 .9
0 . 0
0 . 0
6 .3
6 .3
6 .3
1 0 .4
1 0 .4
0 .7
0 . 8
0 .3
0 .3
1 0 . 0
0 . 0
0 . 0
5
5
5
5
5
1 0 .5
1 0 .5
1 0 .5
1 0 .5
1 0 .5
1 0 .3
1 0 .3
1 0 .4
1 0 .5
1 0 .4
0 .5
0 .5
0 .7
0 .9
0 .0 7 3
0 .0 6 9
0 .0 5 4
7
7
7
1 4 .7
1 4 .7
1 4 .7
1 0 . 6
1 . 2
0 .4
1 0 . 2
0 .3
0 . 1
1 0 . 0
0 . 0
0 . 0
0 .0 7 3
0 .0 6 9
0 .0 5 4
9
9
9
19
19
19
1 0 .3
0 .5
0 . 2
1 0 . 1
0 . 2
0 .0 8
1 0 . 2
0 .3
0 . 1
2
1 0 . 2
0 . 2
0 . 2
0 .3
0 ,4
0 .3
0 . 8
EXPERIMENTS ON PRECIPITATION OF CESIUM PERMANGANATE
IN THE PRESENCE OF POTASSIUM
Experim ents w ith v a r io u s volum es o f th e r e a g e n t were made on 1 .0 0 m l.
o f standard cesium c h lo r id e s o lu t i o n c o n ta in in g p otassiu m c h lo r id e .
T ab le
20 shows th e r e co v e r y o f cesiu m in t h e p r e sen ce o f 5 0 .0 mg. o f p o ta ssiu m
as i t s c h lo r id e .
I t i s se en t h a t th e r e i s no apparent c o - p r e c ip it a t i o n
o f p o ta ssiu m , though th e re co v e r y o f th e cesiu m i s not very good, p o s s i b ly
b ecau se th e high io n c o n c e n tr a tio n in th e s o lu t io n in c r e a s e s th e s o l u b i ­
lity
o f cesium perm anganate.
TABLE 20
RECOVERY OF CESIUM FROM A STANDARD SOLUTION OF CESIUM
CHLORIDE COSTASKING POTASSIUM
NH4 Mn0 4
NH4 Mn0 4
NH4 Mn04
M o la r ity
E q u ivalen t
Volumes
f o r Cesium
E q u iv a len t
Volumes fo r
P otassium
Cesium
R ecovered
mg.
KMCO4
KMn0 4
C a lc u la te d
P r e c ip it a t e d as P o ta ssiu m
mg.
mg.
0 .0 5 4
2
0 . 1 2
9 .5
0 .0
0 . 0
0 .0 5 4
5
0 .2 9
9 .6
0 . 0
0 . 0
0 .0 5 4
9
0 .5 3
9 .5
0 .0
0 . 0
Table
2 1
shows r e co v e r y o f cesium i n th e p r e sen ce o f
p o ta ssiu m a s t h e c h lo r id e .
1 0 . 0
mg. o f
I t i s s e e n t h a t th e r e i s l i t t l e or no ap p aren t
o o - p r e o ip it a t io n o f p o ta ssiu m , and t h a t th e r e c o v e r y o f cesium i s s a t i s f a c ­
to ry .
E v id e n tly th e io n c o n c e n tr a tio n i s not to o high i n t h i s s o l u t i o n .
32
TABLE 21
RECOVERY 01 CES'UM FROM A STANDARD SOLUTION OF CESIUM
CHLORIDE CC.'fTAINING SMALLER AMOUNTS OF POTASSIUM
NH4Mn04
M o la r ity
NB4Mn04
E q uivalen t
V0 1UlTaO3
f o r Cesium
lvE4Mn04
E q u iv a le n t
Yclumes
f o r Potassium
Cesium
Recovered
mg.
KMnCi
KMn04
C a lc u la te d
P r e c i p i t a t e d as Pot as s i un
mg.
ag.
0 .1 6 3
0 .0 5 4
2
2
0 .5 9
0 .5 9
10.0
9 .5
0 .0
0 .0
0 .0
0 .1 6 3
0 .0 5 4
5
5
1 .4 6
1 .4 6
1 0.2
9 .5
0 .4
0 .0
0 .1
•''n
0 .1 6 3
0 .0 5 4
9
9
2 .6 4
2 .6 4
1 0 .3
9 .7
0 .6
0 .0
0 .1
0 .0
0 .0
F iv e d a te r m io a tio n s f o r 5 0 .0 mg. o f cesium i n 1 m l. o f w a te r w ith a
re a g en t o f 0 .1 0 m o la r ity w ere made.
Two o f th e cesium s o lu t i o n s c o n ta in e d
rubidium , one c o n ta in e d p o ta ssiu m , and one c o n ta in e d b o th rubidium and
p o ta ssiu m .
The r e s u l t s a r e shown i n Table 2 2 .
r e co v e r y o f th e cesium w as s a t i s f a c t o r y .
I t w i l l be se en t h a t th e
33
TABLE 2 2
RECOVERY OF CESIUM FROM A CONCENTRATED SOLUTION DI­
CES TUM CHLORIDE CONTAINING OTHER ALKALI CHLORIDE
NH4 Mn04
NH4 Mn04
M o la rity
E q u iv a len t
Volumes
f o r Cesium
0 .1 0 3
0 .1 0 3
0 . 1 0 1
1 .5
1 .5
1 .5
1 .5
0 .1 0 3
1 .5
0 . 1 0 1
NH4 Mn04
E q u iv a le n t
O ther A lk a li
Volumes
Taken
f o r Rubidium
or K
1 5 .8
9 .6
0 .4 4
( 9 .6
{ 0 .4 4
3 .0 mg. Rb
5 .0 mg. Rb.
5 0 .0 mg. K
5 .0 mg. Rb.'l
5 0 .0 mg. K /
Apparent Cesium
Recove red
mg.
4 9 .3
5 0 .2
5 0 .3
4 9 .2
5 0 .0
DETERMINATION OF CESIUM BY A VOLUMETRIC METHOD
Four d e te r m in a tio n s w ere made on 1 .0 0 m l. o f stan dard c e siu m c h lo r id e
s o lu t i o n .
2 . 0 0
a c id .
I n s te a d o f t h e cesiu m permanganate p r e c ip i t a t e b e in g w e ig h e d ,
m l. o f stan dard o x a l ic a c id was added t o i t , t o g e t h e r w ith, s u l f u r i c
The e x c e s s o x a l ic a o id was t i t r a t e d w ith stan dard ammonium perman­
gan ate re a g en t co n ta in e d i n a m icro b u r e t , and th e cesiu m was c a lc u la t e d
from th e volume o f o x a lic a c id needed t o r e a c t w ith t h e cesium perm anganate.
The r e s u l t s , w h ich are shown i n T able 2 3 , were found t o be s a t i s f a c t o r y .
34
TABLE 23
VOLUMETRIC ESTIMATION OF CESIUM
H2 C2°4
M o la r ity
0 .1 5 5
0 .1 5 5
0 .1 5 5
0 .1 5 5
2
iH4 Mn0 4
M o la r ity
H2 c2°4
Volume
m l.
0 .0 5 7 0
0 .0 5 7 0
0 .1 0 0 6
0 .1 0 0 6
NH4 MNO4
Volume
m l.
1 .3 0
1 .3 0
0 .7 5
0 .7 5
2 . 0 0
2 . 0 0
2 . 0 0
2 . 0 0
Cesium
Cesium
Taken R ecovered
mg.
mg.
1 0 . 0
1 0 . 0
9 .9
1 0 . 2
1 0 . 0
1 0 . 0
1 0 . 0
1 0 . 0
STABILITY OF AMMONIUM PERMANGANATE REAGENT
At one p o in t du rin g th e e x p e r im e n ts, a check d e te r m in a tio n on th e
0 .3 2 4 M ammonium permanganate s o lu t io n b e in g u sed a s r e a g e n t gave a cesium
r e c o v e r y o f o n ly 32 p er c e n t.
p a r t i a l l y decom posed.
I t was su sp e c te d t h a t t h i s s o lu t i o n was
A nother check d e te r m in a tio n w ith t h e 0 .3 2 4 M
ammonium perm anganate s o lu t io n ta k en d i r e c t l y from t h e r e s e r v e d s to c k
b o t t l e gave a r e c o v e r y o f 82 p e r c e n t.
T h is n o t o n ly showed t h a t th e
sto c k s o l u t i o n was t h e b e t t e r o f th e tw o, b u t t h a t ammonium permanganate
s o lu t io n may decom pose e x t e n s i v e ly .
T h e r e a fte r , th e r e a g e n ts t h a t were
b e in g u sed w ere sta n d a r d is e d r a th e r f r e q u e n t ly .
In T ab le 24 are l i s t e d
th e r e s u l t s o f su ch ch eck s ta n d a r d is a tio n s f o r n in e d i f f e r e n t r e a g e n ts o f
v a r io u s m o l a r i t i e s t r e a t e d i n v a r io u s w ays.
were a g a in s t pure sodium o x a la te .
A l l t h e s e s ta n d a r d is a t io n s
35
TABLE 24
STABILITY Of AMMONIUM PERMANGANATE SOLUTIONS
E lapsed
Time
Days
M o la rity
Treatment
Reagent 1
0
4
0 .3 0 3
0 .2 9 9
R eagent at
room tem p era tu re.
R eagent 2
0
1 1
18
0 .0 7 6 1
0 .0 7 3 0
0 .0 7 2 1
Reagent
a t room
tem p e r a tu re .
R eagent 3
0
1
5
8
0 .2 6 8
0 .2 7 1
0 .2 6 4
0 .2 6 4
Reagent
r e f r ig e r a t e d .
F i l t e r e d b e fo r e
s ta n d a r d iz in g .
R eagent 4
0
9
0 .1 6 7
0 .1 6 7
Reagent r e f r i g e r a t e d . F i lt e r e d
b e fo r e s ta n d a r d iz in g .
Reagent 5
0
9
0 .1 6 3
0 .1 6 3
Reagent r e f r ig e r a t e d . F i l t e r e d
b e fo r e s ta n d a r d iz in g .
R eagent
0
2
3
0 .0 9 4 8
0 .0 9 5 7
0 .0 9 4 9
6
Reagent r e f r ig e r a t e d .
F i l t e r e d b e fo r e
s ta n d a r d !z in g .
R eagent 7
0
1
0 .0 6 9 6
0 .0 6 9 3
R eagent r e f r i g e r a t e d . F i l t e r e d
b e fo r e s ta n d a r d iz in g .
TABLE 24 (CONTINUED)
E lapsed
Time
Days
M o la r ity
Treatm ent
R eagent
0
3
8
19
0 .0 5 7 5
0 .0 5 7 0
0 .0 5 7 0
0 .0 5 6 5
8
R eagent
r e f r ig e r a t e d .
F i lt e r e d b e fo r e
s ta n d a r d iz in g .
R eagent 9
0
3
4
6
1 0
0 .0 5 4 3
0 .0 5 4 1
0 .0 5 4 4
0 .0 5 4 1
0 .0 5 3 9
R eagent
r e f r ig e r a t e d .
F i lt e r e d
b e fo r e
s ta n d a r d iz in g .
37
I t w i l l be se e n t h a t th e r e a g e n ts k e p t a t room tem peratu re were
l e s s s t a b le th an t h o s e kept aba low te m p e r a tu r e .
For the purpose o f
p r e c i p i t a t i n g cesium th e changes i n th e m o la r i t i e s o f th o s e o f t h i s
secon d group are i n s i g n i f i c a n t over th e p e r io d s l i s t e d .
However,
ammonium permanganate s o lu t io n s cannot be r e l i e d upon t o remain unchanged
o v e r p e r io d s o f many w eek s, ev en when k e p t a t a low tem p eratu re.
F il­
t r a t i o n t o remove any s o li d d e c o m p o sitio n p ro d u cts i s a n e c e ssa r y s te p
f o r s a t i s f a c t o r y r e s u l t s e i t h e r i n s ta n d a r d iz in g t h e s e s o lu t io n s or i n
u s in g them fo r th e d e te r m in a tio n o f cesiu m .
.
GENERAL DISCUSSION
Cesium may be p r e c ip it a t e d q u a n t i t a t i v e l y from a c h lo r id e s o lu t io n
c o n t a in in g 5 mg. t o 50 mg. o f cesium p er m l. by ammonium permanganate
r e a g e n t o f any m o la r ity from about 0 .0 5 t o about 0 .3 2 , p rovid ed t h i s i s
done n ear 0°C .
The volume o f rea g en t may b e a s sm a ll a s 1 .5 tim e s or
a s la r g e a s 9 tim e s t h e t h e o r e t i c a l l y e q u iv a le n t volum e, as dem onstrated
b y t h e d a ta o f T a b le s 7 ,
8
, and 1 0 .
Rubidium a lo n e i n amounts up t o 5 mg. was n ot p r e c ip it a t e d when th e
c o n c e n tr a tio n o f t h e ammonium perm anganate was n ot to o h ig h (T a b le s 11 and
1 2 ).
Rubidium i n amounts up t o 3 mg. was n o t p r e c i p i t a t e d , even w ith a
r a th e r c o n c e n tr a te d r e a g en t (T a b le s 13 and 1 4 ) .
The maximum a llo w a b le
volum es and m o la r it ie s are g iv e n i n T ab le 2 5 .
P otassiu m a lo n e i n amounts up t o 50 mg. was not p r e c ip it a t e d a t any,
bur th e h i g h e s t , c o n c e n tr a tio n o f r e a g en t (T a b le 1 5 ) .
1 0
In amounts up t o
m g ., p o ta ssiu m was not p r e c ip it a t e d a t a n y , in c lu d in g even th e h i g h e s t ,
38
c o n c e n tr a tio n o f th e r e a g e n t, e x c e p t w it h a la r g e volume o f t h e most
c o n c e n tr a te d reagen t (T able 1 6 ).
The maximum a llo w a b le volum es and
m o l a r i t i e s are g iv e n in Table 2 5 .
TABLE 25
MAXIMUM VOLUMES AM) KOLAPJTIES OF AMMONIUM PERMANGANATE
REAGENT ALLOWED WITHOUT PRECIPITATING ONE
ALKALI ALONE IN A CHLORIDE SOLUTION
Maximum
Amount o f
A lk a li
NH4 Mn0 4
M o la r ity
5 mg. Rb.
5 mg. Rb.
0 .1 6
0 .0 7
3 mg. Rb
3 mg. Rb
NH4 Mn0 4
E q u iv a le n t Volumes
f o r 1 0 mg.
Cesium
NH4 Mn04
E q u iv a len t Volumes
For Rubidium or K
2
2 . 6
9
1 1 .5
0 .1 6
0 .3 2
9
4 .3
1 8 .9
9
50 mg. K
0 .1 6
9
0 .5 3
mg. K
0 .3 2
9 .9
2 .9
1 0
Cesium i n amounts betw een 5 mg. and 50 mg. can be p r e c ip it a t e d q u a n ti­
t a t i v e l y by ammonium permanganate r e a g e n t i n th e p r e sen ce o f not more th a n
3 mg. o f rubidium and o f not more th a n 50 mg. o f p o ta ssiu m , p r o v id e d t h a t
t h e c o n c e n tr a tio n o f t h e r e a g en t i s k ep t a s sm a ll as about 0 .1 0 M and th e
volume i s 1 .5 tim e s t h e e q u iv a le n t (T a b le s 1 7 , 18, 1 9 ,2 0 , 2 1 , and 2 2 ) .
RECOMPILED PROCEDURE
On t h e b a s is o f th e r e s u l t s o f a l l th e exp erim en ts th e f o llo w in g
p roced u re may be recommended f o r th e d e te r m in a tio n o f oesium .
Evaporate
39
t o dryne 3 3 i n a 5 0 -m l. Erlenm eyer f l a s k th e s o lu t io n o f c h lo r id e s con­
t a in in g between 5 mg. and 50 mg. o f cesiu m , not more th an e.a eq u al
amount o f p o ta ssiu m , and not more th an 3 mg. o f rubidium .
D is s o lv e t h e
r e sid u e in 1 ml.
o f w a te r .
P la c e th e f la s k c o n ta in in g th e s o lu t i o n o f
a l k a l i c h lo r id e s
in a s a lt e d i c e b a th , and s lo w ly add from a b u ret
6
m l.
o f co ld f r e s h l y f i l t e r e d 0 .1 0 M ammonium permanganate r e a g en t w h ile
s w ir lin g th e s o lu t io n i n th e f l a s k .
bath f o r 10 m in u te s.
A llow th e f la s k t o rem ain i n th e i c e
During t h i s tim e c o o l a w eighed Gooch c r u o ib le ,
p rovid ed w ith a g l a s s f i l t e r mat, o v e r dry i c e , and c o o l some p r o p io n ic
a c id v d th an i c e b a th .
A f t e r th e f l a s k , c r u o ib le , and v e s s e l c o n ta in in g
th e p r o p io n ic a oid have b een c o o le d , f i l t e r t h e p r e c ip it a t e w ith s u c tio n
in t o th e c o ld c r u c ib le f i t t e d t o a fu n n e l i n a f i l t e r f l a s k .
f l a s k and wash th e p r e c i p i t a t e w it h
a o id .
dry.
6
R in se t h e
m l. t o 9 m l. o f t h e co ld p r o p io n io
A llow th e s u c t io n t o c o n tin u e u n t i l th e p r e c ip i t a t e ap pears t o be
Remove th e e x c e s s o f p r o p io n ic a o id ad h erin g t o th e bottom o f th e
c r u o ib le by p r e s s in g t h e c r u c ib le on an ab so rb in g medium w hich le a v e s no
l i n t , such as a paper t o w e l.
an hour a t 110° - 120°C.
Heat t h e c r u o ib le w ith th e p r e c ip i t a t e f o r
A f t e r c o o lin g t h e c r u o ib le i n a d e s ic c a t o r f o r
a t l e a s t 40 m in u te s, vwigh th e c r u c ib le w ith th e p r e c i p i t a t e .
From th e
w eigh t o f th e p r e c i p i t a t e c a lc u l a t e t h e w e ig h t o f cesiu m , cesium c h lo r id e ,
or cesium o x id e .
The f a c t o r s a r e ;
f o r cesium , 0 .5 2 7 8 ; f o r cesium
c h lo r id e , 0 .6 6 8 S ;
f o r cesium o x id e , 0 .5 5 9 3 .
To u se th e v o lu m e tr ic m ethod, in s t e a d o f w eigh in g th e p r e c i p i t a t e ,
d i s s o l v e i t w ith sm a ll p o r t io n s o f h o t w a te r , and t r a n s f e r each s u c c e s s iv e
s o lu t io n t o a 150 m l. b e a k e r , c o n ta in in g a hot (8 0 ° - 9 0 °C .) s o lu t i o n o f
40
5 .0 0 ml. o f 0 .2 5 M o x a l ic a c id and 2 m l. o f c o n cen tra ted s u l f u r i c a o id .
Then w ith a scoop u la t r a n s f e r th e mat w ith rem aining p r e c i p i t a t e .
A fte r
a l l the permanganate i s red u ced , t i t r a t e th e e x c e s s o f o x a la te i n th e
hot
s o lu t io n w ith 0.1CD0M anmonium permanganate s o lu t io n .
S im ila r ly
add
2 m l. o f c o n c e n tr a te d s u l f u r i c a o id t o 5 .0 0 m l. o f th e
0 .2 5 M o x a lic
a c id s o lu t i o n , h e a t th e s o lu t i o n to 80° - 9 0 °C ., and t i t r a t e .
U sing
t o r e p r e s e n t th e volume o f ammonium permanganate i n t h e f i r s t t i t r a t i o n
and V2 "to r e p r e se n t th e volume o f ammonium permanganate i n t h e secon d
t i t r a t i o n , c a lc u la t e cesiu m , cesium c h lo r id e , or cesium o x id e by one o f
t h e f o llo w in g eq u a tio n s*
mg. Cs
* (V 2 - Vx) X 0 .1 0 0 0 X 132 .9 1
mg. CsCl = (V 2 - Vx) X 0 .1 0 0 0 X 1 6 8 .3 7
mg. Cs20 = (V 2 - Yx) X 0 .1 0 0 0 X -2- ~ V 7?
NOTES ON PROCEDURE
1.
I f i t i s known t h a t th e s o lu t i o n o f c h lo r id e s c o n ta in s more th a n
50 mg. o f cesiu m , th e s o l u t i o n may be evap orated i f n e c e s s a r y , t r a n s f e r r e d
t o a v o lu m e tr ic f l a s k , d ilu t e d t o t h e mark, and an a liq u o t u sed f o r th e
d e ter m in a tio n of cesiu m .
2.
The d i l u t e ( 0 .1 0 M) r e a g e n t sh ou ld be f i l t e r e d once each day
t h a t i t i s u se d , im m ed ia tely p r io r t o s ta n d a r d iz a tio n and p r io r t o any
d e te r m in a tio n s .
An unweighed Gooch c r u c ib le f i t t e d w ith 2 g l a s s f i b e r
f i l t e r mats has been found t o remove th e p r e c ip it a t e d manganese d io x id e .
A second f i l t r a t i o n th rou gh a n o th e r c r u c ib le i s made.
I f , a f t e r th e
manganese p r e c ip i t a t e s a r e washed w ith w a te r , an yth in g more th a n a y e llo w
41
d is c o lo r a tio n i s
recommended.
3.
present on th e
3©cond m at, a t h ir d f i l t r a t i o n
is
U s u a lly two are s u f f i c i a n t .
I n order
c o o l t h e f i l t e r c r u c ib le s over dry i c e , a h a l f ­
g a llo n Dewar f la s k was f i t t e d w ith a t h in aluminum p la t e w ith l e g s ,
so t h a t th e p l a t e r e s t e d about 4 .5 cm. from t h e to p o f th e f l a s k .
The
p la t e c o n ta in e d 4 h o le s o f such s i z e as to supp ort a c r u o ib le in each .
Crushed d ry i c e was in tr o d u ce d through th e s e h o le s t o w it h in about 3 cm.
o f th e p l a t e , and th e Dewar was covered w ith a
4.
The p r o p io n ic a c id
lid .
wash liq u id may be c o n v e n ie n tly c o o le d
in a
sm a ll grad u ated c y lin d e r p la c e d i n an 800 m l. b eak er f i l l e d w ith crushed
ic e .
No s a l t i s added t o t h i s i c e b a th .
5.
I t i s w e l l t o w ear
a rubber g lo v e t o h an d le t h e f l a s k and th e
graduated c y lin d e r a s a p r o t e c t io n a g a in s t th e c o r r o s iv e
p r o p io n ic a c id .
a o t io n o f th e
P la c e a sm a ll g l a s s oup or b eaker over th e c y lin d e r o f
p r o p io n ic a o id t o p r e v e n t v o l a t i l i z a t i o n o f th e a c id .
6
.
I f th e v o lu m e tr ic method i s u se d , t h e ammonium permanganate
re a g en t sh ou ld be a t room tem peratu re during i t s
s ta n d a r d iz a t io n and
d u rin g th e t i t r a t i o n o f th e o x a l ic a c id .
SUMMARY
By r e a c t in g aximonium s u l f a t e w ith barium perm anganate, and f i l t e r i n g
o f f th e p r e c ip i t a t e d barium e u l f a t e , a s o lu t i o n o f ammonium permanganate
i s o b ta in e d .
A f t e r t h e s o lu t io n i s d ilu t e d and r e f r ig e r a t e d , th e ammonium
permanganate i s a s a t i s f a c t o r y rea g en t f o r th e s e p a r a tio n o f m oderate
amounts o f cesiu m from sm a ll amounts o f rubidium and from la r g e amounts
o f p o ta ssiu m and f o r th e g r a v im e tr ic d e ter m in a tio n o f cesium i n t h e
p r esen ce o f such amounts o f rubidium and p o ta ssiu m .
The re a g en t g iv e s
q u a n t it a t iv e r e s u l t s , i f i t i s not t o o c o n c e n tr a te d , and i f th e p r e c i o
p i t a t i o n i s made near 0 C.
The g r a v im e tr ic d e te r m in a tio n o f cesium a s
t h e perm anganate by t h i s r e a g en t i s more r a p id th a n t-y any p r e v io u s ly
p u b lish e d m eth od s.
The v o lu m e tr ic d e te r m in a tio n o f cesiu m , by d is s o l v i n g
t h e cesium perm anganate p r e c ip i t a t e w ith an e x c e s s o f o x a l ic a c id and
t i t r a t i n g th e e x c e s s o f a c id w ith standard perm anganate, i s even more
r a p id , inasm uch a s t h e tim e r e q u ired f o r t h e s e o p e r a tio n s i s l e s s th an
t h a t needed f o r d r y in g , c o o lin g , and w eigh in g th e cesiu m permanganate
p r e c ip ita te .
BIBLIOGRAPHY
1.
B a x te r , G. P ., B o y ls to n , A . C ., and Hubbard, R. A .,
o f P otassium Perm anganate," 2 8 , 1336 ( 1 9 0 6 ).
"The S o l u b i l i t y
'W vv
2.
D uval, Clement, " In organ ic T herm ogravim etric A n a ly s is ,"
P u b lis h in g C o., New York, 1953, pp. 3 0 5 , 3 9 1 .
E ls e v ie r
3.
H ille b r a n d , W. F ., L u n d e ll, G. E. F . , B r ig h t, H. A ., and Hoffman,
J . I . , "A pplied In o r g a n ic A n a ly s is ," John W iley & S o n s, I n c . ,
New York, 1953, p . 646.
4.
H il ly e r , J . C ., "D eterm in ation o f th e Common and Rare A l k a l ie s ,"
In d . Eng. Chem. , A n a l. E d ., 9j 236 ( 1 9 3 7 ).
5.
K o lth o ff, I . M., and S a n d e ll, E. B ., "Textbook o f Q u a n tita tiv e
In o r g a n io A n a ly s is ," The M acm illan C o ., New York, 1949, p p . 35 8 , 3 7 3 .
6.
N oyes, A. N ., and Bray, W. C ., "A System o f Q u a lit a t iv e A n a ly s is
f o r th e Rare E lem en ts," The M aom illan C o., New York, 1927, p . 245.
7.
O 'Leary, W. J . and P a p is h , J . ,
" A n a ly tic a l R e a c tio n s o f Rubidium
and Caesium ," In d . Eng. Chem. , A n a l. E d ., J6, 107 ( 1 9 3 4 ) .
8.
P a tte r s o n , A. M., " S o l u b i l i t i e s o f Perm anganates o f t h e A lk a li
M e ta ls," J . Am. Chem. S oo. , 2 8 ,1734(1906).
9.
S c h o e lle r , W. R ., and P o w e ll, A. R ., "The A n a ly s is o f M in era ls and
Ores o f th e Rarer E lem en ts," 2d e d . , C h a rles G r if f in & C o., London,
1940, p . 4 1 .
10.
W e lls , R. C ., and S te v e n s , R. E ., "D eterm in ation o f t h e Common and
Rare A lk a lie s in M in eral A n a ly s is ," I n d . Eng. Chem. , A n a l. Ed. ,
j6 , 439 ( 1 9 3 4 ).
11.
W e lls , R. C ., and S te v e n s , R. E ., "The A in alysis o f P o l l u c i t e ,"
I n d . Eng. Chem. , A n al. E d ., 9 , 236 ( 1 9 3 7 ) .
43
AUTOBIOGRAPHY
I , W allace E. Beebe 1, was born in Ringtown, P e n n sy lv a n ia ,
September 18, 1904.
I r e c e iv e d my secon dary s c h o o l e d u c a tio n in th e
p u b lic s c h o o ls o f R ingtow n.
I n 1923 I was graduated from K eystone S ta te
Normal S c h o o l, now c a ll e d T eachers C o lle g e , K utztown, P e n n sy lv a n ia .
A fte r fu r th e r und ergraduate work a t Muhlenberg C o lle g e I r e c e iv e d th e
B ach elor o f A r ts d egree i n 1929.
I r e c e iv e d th e M aster o f E d u cation
d egree from R u tgers U n iv e r s it y i n 1933, and th e M aster o f S c ie n c e
d egree from The Ohio S t a te U n iv e r s it y i n 1952.
I se r v e d a s an a s s i s t a n t
i n th e Departm ent o f C hem istry a t Ohio S ta te w h ile I was c o m p le tin g th e
req u irem en ts f o r th e d eg ree D octor o f P h ilo so p h y .
44