Neutralisation of 30 gm of a mixture of acetic acid and phenol solutions required 100 ml of 2M sodium hydroxide solution. When the same mixture was treated with bromine water, `33.1` gm of precipitate was formed. Determine the mass percentage of acetic acid and phenol in the given solution.

Explanation

To determine the mass percentage of acetic acid and phenol in the given mixture, we can follow these steps:

### Step 1: Calculate the number of equivalents of NaOH used
The neutralization reaction of the mixture with NaOH gives us the total number of equivalents of acetic acid and phenol.

Given:
- Volume of NaOH solution = 100 mL = 0.1 L
- Molarity of NaOH = 2 M
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