A certain quantity of gas occupies `50 mL` when collected over water at `15^(@)C` and `750 mm` pressure. It occupies `45.95 mL` in the dry state at `NTP`. Find the partial pressure of water vapour at `15^(@)C`.

Explanation

To find the partial pressure of water vapor at 15°C, we can use the ideal gas law and the information provided in the question. Here’s a step-by-step solution:

### Step 1: Understand the given data
- Volume of gas collected over water, \( V_1 = 50 \, \text{mL} \)
- Pressure when collected over water, \( P_1 = 750 \, \text{mm Hg} \)
- Volume of gas in dry state at NTP, \( V_2 = 45.95 \, \text{mL} \)
- Temperature at collection, \( T_1 = 15^\circ C = 288 \, \text{K} \)
- Temperature at NTP, \( T_2 = 0^\circ C = 273 \, \text{K} \)
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