1 \( \text{cm}^3 \) of water at its boiling point absorbs 540 cal of heat to become steam with a volume of 1671 \( \text{cm}^3 \). If the atmospheric pressure \( = 1.013 \times 10^5 \, \text{N/m}^2 \) and the mechanical equivalent of heat \( = 4.19 \, \text{J/cal} \), the energy spent in this process in overcoming intermolecular forces is