An aqueous solution containing `28%` by mass of liquid A `(mol.mass = 140)` has a vapour pressure of `160 mm` at `30^@C`. Find the vapour pressure of the pure liquid A. (The vapour pressure of the water at `30^@C` is `150 mm`.)

Explanation

To find the vapor pressure of pure liquid A, we can follow these steps:

### Step 1: Understand the given data
- The mass percentage of liquid A in the solution is 28%.
- The molar mass of liquid A is 140 g/mol.
- The vapor pressure of the solution is 160 mmHg.
- The vapor pressure of pure water at 30°C is 150 mmHg.

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