The heat of combustion of acetylene is 312 kcal. If the heat of formation of `CO_2` is 94.38 kcal and that of water is 63.38 kcal, calculate `C -=C` bond energy assuming that the bond energy of C-H is 93.6 kcal. Heat of atomisation of carbon and hydrogen are 150 and 51.5 kcal respectively.

Explanation

To solve the problem step-by-step, we will calculate the bond energy of the carbon-carbon triple bond (C≡C) using the provided data and the heat of combustion of acetylene (C2H2).

### Step 1: Write the combustion reaction of acetylene
The balanced equation for the combustion of acetylene (C2H2) is:
\[ \text{C}_2\text{H}_2 + \frac{5}{2} \text{O}_2 \rightarrow 2 \text{CO}_2 + \text{H}_2\text{O} \]
The heat of combustion (\( \Delta H \)) for this reaction is given as -312 kcal.
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