When P2O5 is thrown into excess of water at room temperature, about 75 per cent. of the total dissolved acid is HPO3 and the rest H3PO4. There is no evidence of the formation of H4P2O7. This HPO3 exists as complex and simple molecules, and the proportions of the two may vary widely from one solution to another of the same total concentration. Two changes then take place, a depolymerisation of the (HPO3)n and a hydration of HPO3, of which the former is probably the quickest. The latter change (hydration) does not, as in the reaction studied by Sabatier, follow exactly the same exponential law until all the acid is changed. The two changes are seen most clearly in the G, K curves, Fig. 3, and from these it also appears that the conductivity of HPO3 is considerably greater than that of H3PO4.
|Number of pages||8|
|Journal||Transactions of the Faraday Society|
|Publication status||Published - 1909|