Two grams of benzoic acid `(C_(6)H_(5)COOH)` dissolved in `25.0 g` of benzene shows a depression in freezing point equal to `1.62 K`. Molal depression constant for benzene is `4.9 K kg^(-1)"mol^-1`. What is the percentage association of acid if it forms dimer in solution?

Explanation

To solve this problem, we need to determine the percentage association of benzoic acid when it forms a dimer in benzene. Here are the steps to solve the problem:

### Step 1: Determine the molality of the solution
First, we need to calculate the molality of the solution. Molality (m) is defined as the number of moles of solute per kilogram of solvent.

Given:
- Mass of benzoic acid (solute), \( W_2 = 2 \, \text{g} \)
- Mass of benzene (solvent), \( W_1 = 25 \, \text{g} = 0.025 \, \text{kg} \)
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