The Thermodynamic Constants of the Dithionite (Hydrosulfite) Ion

Abstract

Latimer has pointed out a discrepancy in the literature in the thermodynamic constants for the dithionite (hydrosulfite) ion (S_2O_4^(-2_). The calculated value for the free energy of formation of the ion from the calorimetric data of Berthelot on its oxidation (to bisulfite ion) by oxygen is - 126 kcal., obtained by Latimer with the aid of an estimated molal entropy of 8 cal.,/deg. The value calculated by him from a derived electrode potential given by Jellinek for the dithionite-bisulfite couple is - 138 kcal.

Additional details