Phosphoric acid glacial

Peirce, C. B. (1879). Filling materials of oxide of zinc and glacial phosphoric acid. Dental Cosmos, 21, 696-7. 

Synonyms metaphosphoric acid glacial phosphoric acid. Long chain linear or cyclic metaphosphoric acids of formula (HP03)n are also called poly-metaphosporic acids. 

Ferric metaphosphate, Fe203.3P205.6H20 or Fe(P03)3.3H20, has been prepared 6 by dissolving ferric oxide in glacial phosphoric acid at 100° C. and maintaining the liquid at this temperature for several hours. The salt separates out in small crystals which take the form of pink rhombic plates derived from a monoclime prism. The crystals are decomposed by water. 

Or Dissolve 1 troy ounce glacial phosphoric acid in S fluid ounces distilled water add 40 grains nitric acid, boil to a syrupy liquid, free from the odor of nitric acid, add distilled water to make up to 12 fluid ounces, and Alter. 

As thus obtained, it appears in the shape of a colourless and transparent glass, which slowly dissolves in water. It is hence called glacial phosphoric acid. Its solution causes in solutions of silver a white granular precipitate of monobasic phosphate of silver it also coa lates albumen. But if long kept, or if very rapidly boiled, this solution passes into one of tribasic phosphoric acid, and no longer precipitates silver or coagulates albumen. Here 2 eqs. of water enter into the composition of the acid P O HO + 2H0 = P,0 3H0. 

Glacial acetic acid. See Acetic acid, glacial Glacial phosphoric acid. See Metaphosphoric acid... 

Synonyms Glacial phosphoric acid Phosphoric acid, meta... 

This acid appears to be the glacial phosphoric acid, which had been hastily assumed by recent writers upon this subject to be the pyrophosphoric acid, but is totally different. I shall take the liberty to designate provisionally the acid of the fused biphosphate of soda, the Metaphosphoric acid, from an hypothesis of its constitution to be immediately explained and the fused salt itself, the Metaphosphate of soda. 

Baum6 and Macquer disproved experiments reported by Juncker, Wal-lerius, and Teichmeyer in which other metals were supposed to be converted into mercury (see Vol. II, p. 317). Macquer in 1773 investigated the manufacture of flint glass ( c), and in 1777 he prepared glacial phosphoric acid with Pouilletier de la Salle, who had assisted him in composing his Dictionary. 

---