Assuming that water vapour is an ideal gas, the internal energy change \[\left( \Delta U \right)\] when 1 mol of water is vapourised at 1 bar pressure and \[100{}^\circ C,\] (given : molar enthalpy of vapourisation of water at 1 bar and \[373\text{ }K=41\text{ }kJ\text{ }mo{{l}^{-1}}\] and \[R=8.3\,J\,mo{{l}^{-1}}{{K}^{-1}}\]) will be

• A. \[41.00kJ\,mo{{l}^{-1}}\]
• B. \[4.100kJ\,mo{{l}^{-1}}\]
• C. \[3.7904\text{ }kJ\text{ }mo{{l}^{-1}}\]
• D. \[37.904\text{ }kJ\text{ }mo{{l}^{-1}}\]