Calculate the change in internal energy when 1 mole of liquid water at 1atm and 100 degrees C is evaporated to water vapor at the same pressure and temperature, given that the molar volumes of the liquid and the vapor at these conditions are 18.8 cm^3/mol and 3.02*10^4 18.8 cm^3/mol, and that the latent heat of evaporation is 4.06*10^4 J/mol