Assuming that water vapour in an ideal gas, the internal energy change (`DeltaU)` when 1 mol of water is vaporised at 1 bar of pressure and `100^(@)` C, (Given : Molar enthalpy of vapourization of water at 1 bar and 373 K = 41 kJ `mol^(-1)` and R=8.3 J `mol^(-1)K^(-1)`) will be :

Options

A. 37.904 kJ `mol^(-1)`
B. 41.00 kJ `mol^(-1)`
C. 4.100 kJ `mol^(-1)`
D. 3.7904 kJ `mol^(-1)`

Answer

A