350 Report of the Department of Chemistry of the 



dilute aqueous solution of the acid gave no reaction for inorganic 

 phosphoric acid with ammonium molybdate; the concentrated 

 aqueous solution gave a pure white, crystalline precipitate with 

 ammonium molybdate which, standing at room temperature, 

 remained unchanged for many months but which quickly turned 

 yellowish in color on heating. The reactions of the acid with bases 

 were identical with those previously reported. 



For analysis it was dried in vacuum over phosphorus pentoxide 

 to constant weight at the temperature of boiling alcohol. In drying 

 at this temperature the color darkened somewhat. 



0.3830 gram subst. gave 0.1106 gram H 2 and 0.1517 gram C0 2 . 



0.1839 gram subst. gave 0.1802 gram Mg 2 P 2 7 . 



Found: C = 10.80; H = 3.23; P = 27.31 per ct. 



For inosite hexaphosphate C 6 Hi 8 24 P6 = 660. 



Calculated: C = 10.90; H = 2.72; P = 28.18 per ct. 



For phytic acid according to Neuberg, C 6 H 24 2 7P 6 = 714. 



Calculated: C = 10.08; H = 3.36; P = 26.05 per ct. 



CONCERNING SOME CHEMICAL PROPERTIES OF PHYTIC ACID. 



spontaneous liberation of inorganic phosphoric acid at 

 ordinary temperature and on drying. 



Freshly prepared phytic acid is a practically colorless syrup — 

 especially when, in the concentration of its aqueous solution, the 

 temperature is not allowed to rise above 50°. When the acid has 

 been prepared from a pure salt, free from inorganic phosphate, the 

 free acid does not give any reaction with ammonium molybdate 

 for inorganic phosphoric acid. Whenever such colorless specimens 

 of phytic acid are preserved for any length of time the color always 

 darkens. The change in color is more rapid when the concentrated 

 aqueous solution is allowed to stand exposed to the air or preserved 

 in a well stoppered bottle, than when the acid is kept in the desic- 

 cator; but even under the latter condition the color gradually deepens 

 to light yellow, deep yellow, light brown and finally, after several 

 months, to dark brown or black. When the acid is dried for 

 analysis either in vacuum or in an air bath the color darkens 

 very materially in a short time, especially when dried at 100° or 

 higher. When dried at a temperature of 60° or 78° in vacuum the 

 color darkens somewhat, but very slightly in comparison with that 

 produced at higher temperatures. 



Patten and Hart 10 asserted that the acid turned dark in color 

 on drying at 110° without undergoing any decomposition. As 

 mentioned by Vorbrodt n the grounds for this statement are not 



10 Am. Chem. Journ. 31:570, 1904. 



11 Anzeiger Akad. Wiss. Krakau, 1910, Series A, p. 484. 



