What is value of `DeltaU` for reversible isothernal evaporation of `90g` water at `100^(@)C`? Assuming water vapour behaves as an ideal gas, `Delta_(vap. Water)H = 540cal g^(-1)`

Options

A. `9 xx 10^(3) cal`
B. `6 xx 10^(3)cal`
C. `4.49 cal`
D. None of the above

Explanation

To find the value of ΔU (change in internal energy) for the reversible isothermal evaporation of 90 g of water at 100°C, we will follow these steps:

### Step 1: Calculate the heat supplied (Q)
The heat supplied for the evaporation of water can be calculated using the formula:
\[ Q = m \times \Delta H_{vap} \]
where:
- \( m = 90 \, \text{g} \) (mass of water)
- \( \Delta H_{vap} = 540 \, \text{cal/g} \) (enthalpy of vaporization)
...