The heat of combustion at constant volume at `27^(@)C` of benzene and acetylene are `-800 kcal` and `310 kcal`. Find the heat of polymerisation of acetylene to benzene at constant pressure.

Explanation

To find the heat of polymerization of acetylene to benzene at constant pressure, we can follow these steps:

### Step 1: Write the combustion reactions
1. **Combustion of Benzene (C6H6)**:
\[ C_6H_6 + \frac{15}{2} O_2 \rightarrow 6 CO_2 + 3 H_2O \quad \Delta H_1 = -800 \text{ kcal} \]

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