Heat of formation of `2 mol` of `NH_(3)(g)` is `=90 kJ`, bond energies of `H-H` and `N-H` bonds are `435kJ` and `390 kJ mol^(-1)`, respectively. The value of the bond enegry of `N-=N` will be

Options

A. `-872.5 kJ`
B. `-945 kJ`
C. `872.5 kJ`
D. `945 kJ mol^(-1)`

Explanation

To find the bond energy of the N≡N bond, we can use the given data about the heat of formation of NH₃ and the bond energies of H-H and N-H bonds. Here’s a step-by-step solution:

### Step 1: Write the reaction for the formation of NH₃
The balanced chemical equation for the formation of ammonia (NH₃) from nitrogen (N₂) and hydrogen (H₂) is:
\[ N_2(g) + 3H_2(g) \rightarrow 2NH_3(g) \]

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