Sodium dimetaphosphate

Sodium tri poly phos phaie, NasPsOio. Since this salt must also be annealed, it is a good plan to perform this preparation in a second platinum crucible, annealing on the same sand bath and at the same time as the sodium dimetaphosphate. 

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

The existence of mono- and dimetaphosphates has not been demonstrated in practice, and is theoretically unlikely (Ebel, 1951 Thilo, 1959 Van Wazer, 1958). The possible presence of cyclopentaphosphates and cyclohexaphosphates in a mixture of condensed sodium phosphates was shown by Van Wazer and Karl-Kroupa (1956), followed by Thilo and Schulke (1965). In addition, more highly polymerized cyclic phosphates containing as many as 10 to 15 orthophosphoric acid residues have been observed in some samples of the condensed phosphates prepared by Van Wazer (1958). Furthermore, cyclooctaphosphate (Schulke, 1968 Palkina et al, 1979) and cyclododecaphosphate (Murashova and Chudinova, 1999) have been obtained in the crystalline state. 

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