6j2
E D G A R F. SMITH :\SI)H i I R R Y 1 % . H h R R I S .
,.
1.AHi.E
THE
1-1.
l'(Ifl#i,- Tt,t/siuns sf .7/i.l-tcit.r.r i!f f j c > / z t , t / ti z n d Ch/cJr-u/b?+ill of . ~ + . ~ q l i l / i o ~5P~'vsioti iy- C t . i c = r . r / c , of .?+..'' i.i l.ij../) / / ) I / . i ! f .l[ci.crit:l,. 1 izflor-- Tt'tisiotz (g.Chlo~.oifo?-irrr z f .~,I..T' i s 289.2 7 i / t u . of A7/ci.ciLq,. hlolecules CHCI, in 1 0 0 Illole-
3loleciilcs CEiCI, i l l 100
illole-
ciiles of
'r c i i ~
ciiles of liquid mixtiire.
yaseoiis mixture.
16.97 j0.53 59.47
24.30
0.32.13
63.74 73.2j
1.1j1j
Grams CHCI:,
iii
(>r:ittis
w m of
C,ti, in
CHCl,
vapor.
vapor.
1.4770
iu
iniii.
0.660; 30.6 0.4187 13i".7 o.\ij31 162.2
'i't.11 sioii of
C..li,.
iii
iiiiii.
123.j
\'ulof
iiiii?
mr iii c c .
1032
74.3
IO~CI
50.2
ro,;o
1i:irviii-
1iltt.r-
etcr iii iiiiii
iinl
pressure 111 i i i i i i .
;jg 756 7.49
25
25
[TO 131; C O S T l S ~ ~ E l > . ] .- . - .-.
.
.
. . ....
[ C O S T K I D U T I O X IZKOlI T l I h Jotix I 1 1 I ( K I S O S 1,.1iiOK.\TOKJ' c l f l ~ : \ I I S T K Y , YO. 2.1
OF
T H E ELECTROLYTIC DETESiqINATION OF RUTHENIUil.
F
ROM tiiiie to time efforts liar-e lieeii iiixle i n tliis laboratory to gather iiiforiiiatioii upon tlitt tieportiiietit of the inctals of the platiiiuiii group torvartl tlie electric currelit. Pallncliuiii, platiiiuiii, aiid rhodiuiri Iia\.e I)ecii ~lt.teriniiietl qiiai;titativt.l!., and also separated electrolytically troiii other iiietals of the groul)? g.,plladiuiii from iridiuiii. 'I'lic 1iirrpose of this coiiiiiiiiiiication is to prcseiit data relntiii:,. t o tlic elcctrol!.sis of riitlieiiiiiiii salt solutions. Tlie literature of electrol!-sis cloes iiot coiitaiii an!iiiforiiiatioii upoii this point. Tlie salt upoii which the esperiiiients \\-ereinatlc rvas the double chloride of potassiuiii aiid rutlieiiiriiii. It \ v : i ~prepared b y fusing the finely divided nietnl with pntassiuiii iiitrate n i i t l li!.drositle. This fusioii was iiiatie i i i a silver crucihle. Tlie aqueoiis extract w a s acidified witli liytlrocliloric acid, anti the solution rvas tlieii evaporated to crystallization. Much potnssiuiii chloritlc s e p rated at first, but firially the double salt nppeareti i i i iiiiiiute redcolored iieedles. T h e platiiiuiii dish iii which the electrolytic tlecoiiipositioii \\.as carried out \vas coated upon its iiiiier surface with a la!.er of copper. Iii the first trials the solution of the double salt \vas mixed with three graiiis of sodiuiii acetate, a n d acted upon by a current of X . I).,&= o.oI-o.oj aiiipere. T h e quaiitit!. of tlie ruthenium salt iiot beiiig very abuiidaiit it \vas iiecessar). to coilduct the deteriiiitiatioiis with rather sinal1 aniouiits of material. (2,
ELECTROLYTIC
DETERMINATION
OF RUTHENIUM.
653
T h u s , fifty cc. of the double chloride solution contained 0.0593 gram of ruthenium metal. T h e results of four trials were :
...... 0.0119 gram of ruthenium in five cc. of solution, equal t o 0.0595 gram in fifty cc. z ...... 0.0589 gram in fifty cc. of solution. 3 ...... 0.0593 ' 4 ...... 0.0590 (' I
I'
"
(,
'I
"
T h e metal deposit in each instance was dull black in color. A tendency to sponginess was also observed. As other metals of the platinuni group had been precipitated successfully from a phosphate solution ( A m . Chem. 13, 206) ruthenium was tried under similar conditions. I n the experiments that follow, fifty cc. of the salt solution contained 0.0407 gram of metal. Fifteen cc. of disodium phosphate ( I .0358 sp. gr.) and one cc. of phosphoric acid were added to this solution. T h e current was of the same strength as that used in the first series of experiments. T h e metallic deposits weighed :
I.,
I
.................. 0.0402gram. ................. 0.0407 '(
2.
3..
................ 0.0413
T h e ruthenium in each instance was bright and steel-like in appearance. It was also very adherent. There was not the slightest indication of sponginess. I n the two series just given the deposit of metal was washed first with warm water, and subsequently with absolute alcohol. T h e period of precipitation continued through the night, although six hours were found to suffice for the coniplete deposition of the ruthenium. In a third series of two trials, fifty cc. of the salt solution contained 0.0100gram of ruthenium. T h e phosphate, phosphoric acid, and the current were the same as in the series immediately preceding. Results : I 2
............ 0.0101gram ruthenium. ............ 0 . 0 1 ~
..
T h e deposits, a s before, were bright and apparently crystalline. Mention has already been made that palladium and platinum could be separated electrolytically from iridium ( A m . Chent. J., 16, 435) when present together with the latter in a phosphate solution. T h i s was, however, not found possible with rhodium, although this metal was successfully deposited from a similar
654
E D G A R I:.
S M I T H ASI?
II.IKKY
13.
II.\RKIS.
TIII:
solution. As rutlieiiiurii, from the results just given, allies itseif with palladiuni. platiiiuin, arid riiociiuiii. so far as its deposition from a pliosphnte solution was c o n ~ e r i i e d ,it seemeti d iiiterest to ascertairi whether a separatioii it from ii-idiurii coiil(1 1,e effected. Sc j m i x f lbii qf R Z I ~i 2~ 7~ 7 C ~.?in ~/ iLi In’di/(iii .-13 e re a x ai 11 ;i so111 tioii of rutheiiiuiii \\-as used in fiit!. cc. of which there was n . o ~ o o graiii of rutheuiiiiii. T o this were added ten cc. of ail iridium solution (equal to one-tenth gram’ of iridium) ten cc. of disndiuiii phosphate, I .03j8sp. g r . , aiid three cc. of phosphoric acid. T h e curl-eiit was S . ll.,rL=0.01 ampere. I t nctetl through tlie night. T h e deposit of rutlieiiiuiii iii each of thc three esperinieiits wis txiglit, metallic. a n d perfectly adherent. I t vas waslied and dried as in the cleteriiiiiiatioiis clescritml in tlic preceding lines. Results : (if
I..
..........
2
o.0104g r a m of rut1ieniui:i. 0.00~6 ’ “
3 ............
. . . Additional experiments on tlie separation of the two metals mere made with similar result.;. I t would be of interest and i.alue to study the conduct of ruthenium in alkaline solutions. TT.’oliler’ observed that the metal could be quickly brouglit into solutioii n.hen the current acted upon it in the presence of an alkali. I t is altogether probable that, under such conditions. its separation from the other metals of the group could be quite readily brought about, but lack of material will, at least for the present, prevent any such iiir.estigation. 0.UlOO
V S I Y E X S I T T OF p E X S S \ I~V.~Xl.l.
[ C O S T K I X U T I O N F R O M T H E J O H S I r . 4 R K l S O S 14.i130K.+TOR\’
01‘
CH~~MISTKY No. . 5.1
T H E ACTION OF PHOSPHORUS PENTACHLORIDE UPON T H E DIOXIDES O F ZIRCONlUfl A N D THORIUfl. BY
EDGAR
S
F. S M I T H
AXNn H A R K S B. I f A R K I S . Hecclvrd hlay 3 1 , ~ H g j .
O U E years ago Weber ( / a h . rK59, 7 7 ) studied the action
of phosphorus pentachloride upon itiorgaiiic oxides, such as those of silicori, titanium, arid tin, and demonstrated that the lriiiri.
Chum. (l,tcb
