Zinc pyrophosphate


Zinc pyrophosphate is an ionic inorganic chemical compound composed of Zn2+ cations and pyrophosphate anions.

Preparation

Zinc pyrophosphate can be obtained from the thermal decomposition of zinc ammonium phosphate.
It can also be obtained from the reaction between sodium carbonate, zinc oxide, and ammonium dihydrogen phosphate.
It is also produced when a strongly acidic solution of zinc sulfate is heated with sodium pyrophosphate.
Another method is precipitating zinc as a phosphate, then heating over 1123 K.

Properties

Zinc pyrophosphate is a white crystalline solid that is insoluble in water. On heating in water, it decomposes to form Zn32 and ZnHPO4. It crystallizes in the monoclinic system. The α-form crystallizes at low temperatures and the β-form crystallizes at high temperatures.

Uses

Zinc pyrophosphate is used as a pigment. It is useful in gravimetric analysis of zinc.