Chemistry

Problem

A substance X has a molar enthalpy of vaporization of

41.5\,\text{kJ}\,\text{mol}^{-1}

and a molar enthalpy of fusion of

8.2\,\text{kJ}\,\text{mol}^{-1}

. Calculate the enthalpy change (include sign) when

1.5\,\text{mol}

of X(g) at its boiling point is converted to X(s) at its melting point.