1.7 Calculate the change in internal energy when 1 mole of liquid water at 1 atm and 100 °C is evaporated to water vapour at the same pressure and temperature, given that the molar volumes of the liquid and the vapour under these conditions are 18.8 cmVmol and 3.02 ×

104cm3/mol, and that the latent heat of evaporation is 4.06 × l04 J/mol.