Conductance, viscosity and density studies have been made on the solutions of trans-dichloro-bis(ethylenediamine) Co(III) chloride and trans-dibromo-bis(ethylenediamine) Co(III) bromide in different compositions of water+methanol, +ethanol and +n-propanol at different temperatures. The conductivity data have been analyzed by Shedlovsky technique. The limiting molar conductance, association constants and various thermodynamic parameters have been evaluated. The density data have been used to calculate apparent molar volume and apparent molar expansibility. The viscosity data have been analyzed by means of Jones-Dole equation.