Calculate the C-C bond enthalpy from the following data :
`2C("graphite") + 3H_(2)(g), to C_(2)H_(6)(g) Delta_(r)H^(@) = -84.67mkJ`
`C("graphite"), to C(g) Delta_(r)H^(@) = 716.7kJ`
`H_(2)(g), to 2H(g) Delta_(r)H^(@) = 435.9 kJ`
Assume 416 kJ as the C-H bond enthalpy.

Explanation

To calculate the C-C bond enthalpy from the provided data, we will follow these steps:

### Step 1: Write the target reaction
We need to find the bond enthalpy for the C-C bond in ethane (C2H6). The reaction we want to consider is:
\[ \text{C}_2\text{H}_6(g) \rightarrow 2\text{C}(g) + 6\text{H}(g) \]

### Step 2: Identify the given reactions
1. \( 2\text{C}(\text{graphite}) + 3\text{H}_2(g) \rightarrow \text{C}_2\text{H}_6(g) \quad \Delta_rH^(@) = -84.67 \text{ kJ} \) (Equation 1)
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