V O L U M E 28, N O . 8, A U G U S T 1 9 5 6
1353
silica. Ammonium hgdroside has been used instead of sodium hydroxide as a final regenerate because of the difficulty encountered in removing sodium hydroxide completely from the column. DETERMIN.4TIOS O F SILICATE AND IONIC MATERIAL
Thc :tnnlytical procedure for the determination of silicate is essentidly t,hat of I 3 ~ i t i r i g(3),modified slightly t,o decrease the volume of sugar solution lost through testing. Sugars do not interfere with the t,est. Prepare the stock silica solution by dissolving about 7 ml. of sodium silicate solution (-10 to 42 Be.) in 2 liters of distilled x-ater and filtering through a fine sintered-glass fnnnel. Det,ermine the concentration of silica in the resulting clear solut,ion gravimetrically and dilute as required t o prepare standard solution having a concentration of about 0.001 nig. of silica.per nil.-e.g., stork soliltion containing 2.1 mg. of silica per ml., diluted 2 t o 1O00. Prepare other reagents as desrrihed by €hinting. For analytical determinations, use 10 ml. of sample (diluted if necessnry to give a silica content of about 1 t o 5 y per ml.), ~ with two exceptions: Cse 0.1 h w e e d as described b , Bunting as much of each reagent and read the absorbance a t 610 mp. Present st>ndieeshowed that the spectrophotomrtrir riirvc has R shoulder a t 600 to 650 m p and a peak a t 815 mp. Calculate the concentration of silica from the relation C = K D , where C is the concentration of silica in milligrams per milliliter, 1) the observed absorbance, and K a constant determined from a standard silica solution run at' the same time. As the volumes of reductant and molybdate reagents used w r e only 0.1 ml., experiments were conducted to determine the efi'cct of varying the amounts of reagent. These experiments intliixted that these volumes need not, be measured x i t h high : w c : i i i ~ : i c - ~ ' . T h e nse of four times as much of the molybdate re:tgrnt :is specified had 110 effect, although using half as much as * I w i f i t v l loawed the ahsorbsrice ahout 4 0 5 .
ACKNOWLEDGMENT
T h e authors wish to express t,heir appreciation to Allene Jeanes for her interest, and assistance in planning and carrying out this study. They also are indebted t,o T. A. 1IcGuire for gravimetric determination of silica, and RI. 0. Bogard and E. H. 3Ielvin for preparation of the spectrophotometric curve. LITERATURE CITED (1) Bailey, J. AI., Whelan, W.J., Peat, S..J . Chern. SOC.1950, 3692. (2) Bauniann, \T. C., Eirkhorn, I., Wirth, L. F., Ind. Eng. Chem. 39, 1453 (1947). (3) Bunting, W.C., IND. Esc,. CHEM.,~ N A L ED. . 16, 612 (1944). (4) Calise, I-.J.. Lane, AI., Chem. Eng. Progr. 44, 269 (1948). Asir.. ED. 18, 499 (1946). (5) Dreywood, Roman, IXD.ENG.CH (6) Gross, D., Blanc-hard, P. H.. Be J.. J . Chem. SOC.1954, 1726. (7) Hulnie, d.C., .\Tuture 171, 610 (1953).
.
(8) Jeanes, Allene, TVilham, C. A., Jones. H. W.,Tsuchiya, H. AI., Ili.t, ('. E.. .I. Arn. Chem. SOC.75, 5911 (1953). (9) Lindsay, F. K., D'Amico. J . S., I n d . Eng. Chem. 43, 1085 (1951). (10) Alontgomery, E. AI., Weakley, F. B., Hilbert, G. E., J . .4m. Chern. SOC.71, 1682 (1949). (11) Phillips, J. D.. Pollard, S a t u r e 171, 41 (1953). (12) Rebenfeld. L.. Pacsu, E., J . Am. Chem. SOC.75, 4370 (1953). (13) Roseman, S., Abeles, It. H., Dorfman, A , , A r c h . Riocherri. R i o p h y s . 36, 232 (1952). (14) Sowden, J. C., J . A m . C h e m . SOC.7 5 , 4 4 8 7 (1954). (15) Whistler, K . L., Science 120, 899 (1954). (16) Whistler. R . L., Durso, D. F., J . A m . Chem. SOC.72, 677 (1950). for review January 9 , 1956. .Iccepted April 26, 1956. The RECEIVED mention ,of firm names or trade products does not imply that they are endorsed or recommended by the U. S. Department of hgriculture over other firms or similar products not mentioned.
CRYSTALLOGRAPHIC D A T A
132. Uranyl Oxalate Trihydrate, UOPCP04.3Hn0 EUGENE STARITZKY and
D O N T. CROMER
The University of California, Los Alarnos Scientific Laboratory, Los Alamos, N.
M.
oxalate trihgdrate was prepared by adding escess L of oxalic acid to a dilute solution of uranyl nitrate in l.lf nit,ric acid and digesting a t 80" C. I RASYL
C R Y S T A L I\IORPHOLO(iY
tem and Class. llonoclinic, prismat,ic. .Xxial Elernrnts. u : h : c = 0.329:1:0.552; p = 98.2" (calculated from the unit rpll dimensions). Habit. Tahular { O l O l , bounded by (Ollb, 11111, [ i l 3 ) . Intrrxonal .\ngle. { 100) A { 101 ) = 53.2 .
X-RAYl>II;FR.4CTIOX DATA Space Group. P2,ic ( C z h ) . Cell Dimensions. 00 = 5.61 A , ; bo = 17.04 A.; cg = 9.41 A , : 8 = 98.2"; cell volume 890 A.3. Formula Weight's per Cell. 4. Formula Weight. 112.14. Ilensity. 3.07 grams per cc. (x-ray); 3.076 (flotation). OPTICAL PROPERTIES
Tlcfractive Indices (5893 -4.).n s
=
1.476; n~
=
1.486: r t ~=
Figure 1. Orthographic projection of crystal of uranyl oxalate trihydrate on (010)
ANALYTICAL CHEMISTRY
1354
Partial Powder X-Ray Diffraction Pattern of Uranyl Oxalate d. A,.
Calcd. 8.52 8.17 6.29 5.55 5.28 4.89)) 4.85 4 . R6j
hkl
4 , Odl
e
b
d , A.,& Obsd.
d, A., Calcd.
d, A,, Obsd.4
8.47
e:25
'80
5:i3
io
8.51
4.87
55
4.62
33
3: 34 3.28 2.90 2.85 2.82 2.76 2.70 2.63 2.55 2.50
3.75
..
4.49 4.38 4.33 i: i 0 i6o 4 26 .. 4:07 4 OR 15 3.98 .. 3 97 3:94 50 3.87' 3.85 :5 3,86,' Philips Il4.6-nirn.-diameter powder camera, Straumanis mounting: X(CuKa) = 1.5418 A. Relative penk intensities above background, from densitometer measurements.
1.684; geometric mean l.5303. Molecular refraction 41.4 cc. Optic Orientation. X = b; Y A c = 58'. Optic Axial Angle (5893 .4.).21.2 = 31 O with strong dispersion T
hkl
I/I>b 85
> F.
I/Ii
b
?n .. 5
..
10 35 20 45 15 10 10 15 30 20
Color. Tellow with absorption Z > Y M X . Fluorescence. Strong, excited by mercury vapor lamp. W O R Kdone under t h e auspices of the Atomic Energy Commiseion.
133.
Hendecahydrogen Diuranyl Pentaphosphate, H,,(UO,),(PO,),
EUGENE STARITZKY and DON T. CROMER The University of California, Lor Alarnor Scientific Laboratory, Los Alamos,
ESUECAHYDROGES
diuranyl pentaphosphate was crystal-
H lized from a hot solution 7 M in phosphoric acid and 1M in uranium dioxide. Chemical analysis. 54.1?6 UO,, 45.870 PO4, calculated 52.61% UOZ, 46.28% Pod.
hkl
Systrrii and Class. Monoclinic, prismatic. .Axial I.:lements. a : b : c = 0.8143:1:0.5397; p = 113'1'. I
C
C
Partial Powder X-Ray Diffraction Pattern of H,~(uo~)~Po~)~ d , A., 4 A.,
110
C R Y ~ T XMORPHOLOGY I.
l-
N. M.
1
F
0 -
Figure 1. Orthographic projections on (100) and (010) of crystal of hendecahydrogen diuranyl pentaphosphate
020 011 200 121 02 1 210 030 130 220 -121 112 202 231 940
212 002 211 310 131 321 140 z22 141 922 241 122 ..-
0 0
-
Calcd. 8.35 6.97 6.15 5.21 5.00
$:%} 4.65
4,244 4.175 4.007
3:;)
3 490 3.484 3 4811 3 425) 3 418 3 372 3 3711 3 195 3.136 3.074
Meas.a 8.32 6.91 6.14 5.20 4.97 4.89 4.67 4.23 4.15 4.00 3.59
I/Il b 25 20 100 15
50
