A reversible isothermal evaporation of 90 g of water is carried out at `100^(@)C`. Heat of evaporation of water is 9.72 kcal `mol^(-1)`. Assuming water vapour to behave like an ideal gas, what is the change in internal energy of the system ?

Options

A. 48.6 kcal
B. 52.23 kcal
C. 44.87 kcal
D. 56.06 kcal

Explanation

To find the change in internal energy of the system during the reversible isothermal evaporation of water, we can follow these steps:

### Step 1: Calculate the number of moles of water
The number of moles (n) can be calculated using the formula:
\[ n = \frac{\text{mass}}{\text{molar mass}} \]
Given:
- Mass of water = 90 g
- Molar mass of water = 18 g/mol
...