Molar volumes and heat capacities of electrolytes and ions in nonaqueous solvents: 1. Formamide

Apparent molar Volumes and heat capacities of 27 electrolytes have been mea sured as a function of concentration in formamide at 25 degrees using a ser ies-connected flow densimeter and Picker calorimeter system. These data wer e extrapolated to infinite dilution using the appropriate Debye-Huckel limi ting slopes to give the corresponding standard partial molar quantities. Io nic Volumes and heat capacities at infinite dilution were obtained by an ap propriate assumption based on the reference electrolyte Ph4PBPh4 (TPTB). Th e ionic Volumes, but not the heat capacities, agree reasonably well with pr eviously published statistically based predictions. The Values obtained are discussed in terms of simple models of electrolyte solution behavior and a number of interesting features are noted, including, possible dependencies of ionic Volumes on solvent isothermal compressibility and of ionic heat c apacities on solvent electron acceptor abilities.