(use the test of orthophosphates, unless the instructions specify the use of the pyrophosphate test or indicate that the product is to be lgnited before performing the test) with silver nitrate TS Neutral solution of orthophosphate yield a yellow precipitate that is soluble in 2 N nitric acid and in 6 N ammonium hydroxide With ammonium molybdate TS, acidified solution of orthophosphate yield a yellow precipitate that is soluble in 6 N ammonium hydroxide This precipitate may be slow to form with silver nitrate TS, pyrophosphate obtained by ignition yield a white precipitate that is soluble in 2 N nitric acid and in 6 N ammonium hydroxide With ammonium molybdate TS, a yellow precipitate that is soluble in 6 N ammonium hydroxide is formed