Sodium ammonium orthophosphates pyrophosphate

Suggested ammonium phosphate to fireproof theatre curtains Heteropolyacids discovered Sodium pyrophosphate Na4P207 first characterised First P-containing striking matches Preparation of first metal-phosphine complex Historical classification of orthophosphates, pyrophosphates and metaphosphates. Glassy metaphosphates reported Observed enzyme activity in test tubes and first enzyme diastase discovered... 

Pyro- and metaphosphates give the ammonium molybdate test on warming for some time this is doubtless due to their initial conversion in solution into orthophosphates. The chief differences between ortho-, pyro- and metaphosphates are incorporated in the following table. The student should carry out all the tests. To study these reactions use freshly prepared solutions of sodium pyrophosphate and sodium metaphosphate. 

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