Abstract
The volume changes on mixing have been measured at 25, 35, and 45 �C for the following binary systems : acetone+acetonitrile, acetone+nitromethane, acetonitrile+nitromethane and each of these polar components with benzene and with carbon tetrachloride.The sign and concentration dependence of the volume changes on mixing of these systems follow closely the excess entropy changes on mixing calculated from the liquid-vapour equilibrium data and heats of mixing previously measured in these laboratories.