162.
No powder data have been reported in the literature.
Thorium Orthophosphate, Th,(PO,),
JAGDISH SHANKAR and
P.
X-RAYDIFFRACTION DAT-4. a = 10.55 A., b = 10.66 A., c = 8.80 A. B = 1106’41’.
G. KHUBCHANDANI
Chemistry Division, Atomic Energy Establishment (Trombay), Bombay, India
X-Ray Powder Diffraction Data for Thorium Orthophosphate Irel.
8 45 5 31 5 06 4.54 4.23 3.86 3.68 3.47
2.76 2.68 2.55 27 more
8 47 5 32 5 04 4 56 4 23 3 87 3.66 3.49
2.76 2.66 2.54
VV.V S S
V.IV. V.S. T-.K. V.W.
s.
W. V.W. V.W.
001 020 200 021 002
201
220 3o i
132
040
041
2.51 2.34 2.29 2.13 2.08 2.02 1.98 1.95 1.94 1.89 1.85 1.82 1.79 1.78 1.75 1.73
2.51 2.33 2.28 2.12 2.08 2.02 1.98 1.95 1.94 1.88 1.84 1.82 1.79 1.77 1.75 1.73
M.S.
S.
hl.S. V.W. K.
V.W. V.TT.
w.
IT. IT.
IT. IT.
IV .
w.
“
hkl 222
302
h1.S. h1.S.
Formula Weights. 2. Density. 3.85, 3.77 (calculated). Crystal System. Monoclinic. S m c e G r o w . Possiblv P2, Pm, or P2im. T h e x-ray powder diffraction data were obtained using a camera 143.2 mm. in diameter and copper K radiation with nickel filter.
420 050 (004) 014 500 510 242 402 529 343 35 i 350 060 169 161
indexable lines w r e observed.
I
ACKNOWLEDGMENT
Thorium orthophosphate was prepared b y Y. W. Gokhale of this establishment, t o whom grateful thanks are due. LITERATURE CITED
(1) Peiser, H. S., Rooksby, H. P., Wilson, A. J. C., “X-Ray Diffraction by
Polycrystalline Materials,’’ Institute of Physics, London, 1955.
HoRIuhf orthophosphate when prerpared from a solution of the thorium salt is obtained as a colloidal gel. On being heated t o 1000” C. in a n atmos-
phere of nitrogen, the gel yields a polycrystalline mass. The crystal parameters were deduced b y indexing a powder photograph b y Ito’s method ( I ) .
CONTRIBUTIONS of Crystallographic Data to be published in ANALYTICALCHEMISTRY should be sent to W. C. McCrone, 500 East 33rd St., Chicago 16, Ill.
Formamide as an Extraction Solvent in Karl Fischer Method for Determining Moisture in Lactose and Maltose SIR: In the recent review article on food (5), a reference was given (2) which pointed out that the Karl Fischer moisture method applied to ordinary skim or whole milk powders does not include all of the water of crystallization of the lactose. Previously (6), i t has been reported that as a result of the insolubility of maltose and lactose in both methanol and the Karl Fischer reagent, these materials can be determined only after preliminary extraction, and when the materials are finely ground. Formamide has been used t o replace methanol as the extraction solvent for the determination of moisture in some food products, including cake mixes containing dried milk solids (3, 4). As lactose and maltose are soluble in formamide, it appeared to be a superior extraction solvent when these sugars, or perhaps products containing them, are t o be analyzed for moisture by the Karl Fischer method. Using the procedure previously de-
scribed (4, we have obtained the following results and compared them with a vacuum oven method ( 1 ) . The sugars were the monohydrates of analytical reagent grade lactose and maltose. X o stirring time was required and the samples were titrated as soon as they were dissolved.
It can be concluded that formamide is a practical extraction solvent for use in the Karl Fischer method, to determine both the water of crystallization and adsorbed water in lactose and maltose. Formamide might readily be adapted for use in products that contain these sugars. LITERATURE CITED
Comparison of Fischer and Oven Methods
Material Lactoseo Maltose“
a
% Moisture Fischer Oven 5.05 5.05 5.09
5.06 5.02 5.01
5.63 5.59 5.61
5 58 5.64 5.57
Calculated % ’ H20 for monohydrates
of lactose and maltose = 5.00%.
(1) Assoc. Offic. Agr. Chemists, “Methods of Analysis,” 8th ed., p. 265, 1955. (2) Kumetat, K., Australzan J . Dairy Technol. 10, 114 (1955). (3) McComb, E. A., NcCready, R. M., J . Assoc. O ~ CA.g r . Chemists 35, 437 (1952 ). (4) McComb, E. A., Wright, H. M., Food Technol. 8 , 73 (1954). (5) Von Loesecke, H. IT., ANAL. CHEM. 29, 647 (1957). (6) Zimmermann, A., Fette u. Seifen 46, 446 (1939).
ELIZABETH A. MCCOMB Western Regional Research Laboratory, Albany 10, Calif. VOL. 29, NO. 9, SEPTEMBER 1957
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