The bond dissociation energies of gaseous `H_(2),C1_(2)`, and `HC1` are `100, 50`, and `100 kcal mol^(-1)`, respectively. Calculate the enthalpy of formation of `HC1(g)`.

Explanation

To calculate the enthalpy of formation of HCl(g), we can use the bond dissociation energies provided for H2, Cl2, and HCl. The enthalpy of formation can be determined using the following steps:

### Step 1: Write the Balanced Reaction
The formation of HCl from its elements can be represented by the following balanced equation:
\[ \frac{1}{2} \text{H}_2(g) + \frac{1}{2} \text{Cl}_2(g) \rightarrow \text{HCl}(g) \]

### Step 2: Identify Bond Dissociation Energies
We have the following bond dissociation energies:
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