Chemistry · THERMODYNAMICS

For the vaporization of \( 1.0\text{ mol} \) of water at \( 100^\circ\text{C} \) and \( 1\text{ bar} \), the enthalpy of vaporization \( \Delta_{\text{vap}}H \) is \( 40.66\text{ kJ}\cdot\text{mol}^{-1} \). Assuming water vapor behaves as an ideal gas and the molar volume of liquid water is negligible, the change in internal energy \( \Delta_{\text{vap}}U \) is: (Take \( R = 8.314\text{ J}\cdot\text{K}^{-1}\cdot\text{mol}^{-1} \))

1. \( 43.76\text{ kJ}\cdot\text{mol}^{-1} \)
2. \( 39.83\text{ kJ}\cdot\text{mol}^{-1} \)
3. \( 37.56\text{ kJ}\cdot\text{mol}^{-1} \)
4. \( 40.66\text{ kJ}\cdot\text{mol}^{-1} \)