engleski

Thermodynamic Studies of Hydrobromic Acid in Acetone-Water Mixtures (10, 30 and 50 wt-%) from Electromotive Force Measurements

The emf of the cell: Pd, H_2(g) / HBr(m), x wt-% acetone-water mixture / AgBr, Ag was measured with x=10, 30 and 50 at temperatures 15, 25 and 35^oC in the molality range for HBr from 0.003 to 0.1 mol kg^-1. From these data the standard potentials for Ag/AgBr electrode are obtained, and used in calculations of: (a) the standard thermodynamic quantities for the cell reaction and the reaction of HBr formation, (b) the mean activity coefficients of HBr, (c) the primary medium effect, and (d) the standard thermodynamic quantities for transfer of HBr from water to the acetone-water mixed solvents. On the basis of the values obtained under (d), the spontaneity of the transfer process for HBr, as well as the acid-base properties of mixed solvents and their structure, are discussed.

hydrobromic acid; acetone-water mixtures; potentiometry; thermodynamic quantities

projekt II/1-1975