When 0.4 g of acetic acid is dissolved in 40 g of benzene, the freezing point of the solution is lowered by 0.45 K. Calculate the degree of association of acetic acid. Acetic acid forms dimer when dissolved in benzene.
(`K_(f)` for benzene = 5.12 K kg `mol^(-1)` at.wt. C = 12, H = 1, O = 16)

Explanation

To solve the problem of calculating the degree of association of acetic acid when dissolved in benzene, we will follow these steps:

### Step 1: Identify the given data
- Weight of acetic acid (solute), \( W_b = 0.4 \, \text{g} \)
- Weight of benzene (solvent), \( W_s = 40 \, \text{g} \)
- Freezing point depression, \( \Delta T_f = 0.45 \, \text{K} \)
- Freezing point depression constant for benzene, \( K_f = 5.12 \, \text{K kg mol}^{-1} \)
- Molar mass of acetic acid, \( \text{C}_2\text{H}_4\text{O}_2 = 2(12) + 4(1) + 16 = 60 \, \text{g/mol} \)
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