The vapour pressure of water is `12.3 kPa` at `300 K`. Calculate vapour pressure of `1` molal solution of a solute in it.

Explanation

To calculate the vapor pressure of a 1 molal solution of a solute in water, we will use Raoult's Law, which relates to the lowering of vapor pressure when a solute is added to a solvent.

### Step-by-Step Solution:

1. **Identify Given Values:**
- Vapor pressure of pure water (P₀) = 12.3 kPa
- Molality of the solution (m) = 1 molal
- Molar mass of water (H₂O) = 18 g/mol
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