If water vapour is assumed to be a perfect gas, molar enthalpy change for vapourisation of 1 mol of water at 1 bar and `100^(@)C` is `41 KJ mol^(-1)`. Calculate the internal energy, when i) 1 mol of water is vaporised at 1 bar pressure and `100^(@)C` ii) 1 mole of water is converted into ice.

Explanation

To solve the problem, we need to calculate the internal energy change for two processes involving water:

1. The vaporization of 1 mol of water at 1 bar and 100°C.
2. The conversion of 1 mole of water into ice.

### Part i: Vaporization of 1 mol of water

1. **Identify the given data:**
...