$1 \mathrm{~kg}$ of water at $100^{\circ} \mathrm{C}$ is converted into steam at $100^{\circ} \mathrm{C}$ by boiling at atmospheric pressure. The volume of water changes from $1.00 \times 10^{-3} \mathrm{~m}^{3}$ as a liquid to $1.671 \mathrm{~m}^{3}$ as steam. The change in internal energy of the system during the process will be

(Given latent heat of vaporisaiton $=2257 \mathrm{~kJ} / \mathrm{kg}$, Atmospheric pressure = $\left.1 \times 10^{5} \mathrm{~Pa}\right)$