Potassium tetrametaphosphate

Potassium tetrametaphosphate crystallizes with two molecules of water and becomes anhydrous at 100°C. Above this temperature the anhydride takes up water from the atmosphere and goes over to the high-molecular... 

Sodium tetrametaphosphate, Na4P40,2, can be prepared by cautious alkaline hydrolysis of P4O10 (4.49), while certain tetrametaphosphates, M2P4O12 (M = Cu, Mg, Mn, Ni, Co, Fe, Zn, Cd), are produced directly, in preference to long-chain polyphosphates, by heating the appropriate MH2PO4 salts (5.170). Sodium or potassium tetrametaphosphate can be obtained from some of these salts by the action of aqueous alkali sulphide (5.171). 

K2P20 Potassium dimetaphosphate. Na2P209, Sodium trimetapnosphate. Pb2P4012, Lead tetrametaphosphate. (NH4)6PsP15, Ammonium pentametaphosphate. Na4P4019, Sodium hexametaphosphate. 

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