orthophosphoric acid en · NOUN
Etymology
From ortho- + phosphoric acid.
Meanings
-
(uncountable) Ordinary phosphoric acid, H₃PO₄
Metaphosphoric acid gives a white precipitate with nitrate of silver solution; orthophosphoric acid does not give any, save on the addition of an alkali, and the precipitate then produced is yellow.
1861, William Odling, A Manual of Chemistry, Descriptive and Theoretical, Part 1, page 297:With the exception of the fertilizer products, most phosphorus compounds are derived from orthophosphoric acid, produced by the oxidation of elemental phosphorus.
2000, Nicholas P. Cheremisinoff, Practical Guide to Industrial Safety: Methods for Process Safety Professionals:Evaporate 25 cc. of orthophosphoric acid solution to dryness, setting the burner beneath the dish and adjusting the flame so that the tip does not quite touch the dish.
1918, Herbert Royl Smith, The Laboratory Study of Chemistry, page 124: