The vapour pressure of pure liquids A and B at 400 K are 450 and 700 mmHg respectively. Find out the composition of liquid mixture if total vapour pressure at this temperature is 600 mmHg.

Explanation

To solve the problem, we will use Raoult's law, which states that the total vapor pressure of a solution is equal to the sum of the partial pressures of each component in the mixture.

### Step-by-Step Solution:

1. **Identify Given Values:**
- Vapor pressure of pure liquid A, \( P_{A0} = 450 \, \text{mmHg} \)
- Vapor pressure of pure liquid B, \( P_{B0} = 700 \, \text{mmHg} \)
- Total vapor pressure of the mixture, \( P_{total} = 600 \, \text{mmHg} \)
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