Calculate `Delta_(f)H^(Theta) ICI(g)` from the data
`DeltaH` dissociation `CI_(2)(g) = 57.9 kcal mol^(-1)`
`DeltaH` dissociation `I_(2)(g) = 36.1 kcal mol^(-1)`
`DeltaH` dissociation `ICI(g) = 50.5 kcal mol^(-1)`
`DeltaH` sublimation `I_(2)(g) = 15.0 kcal mol^(-1)`

Explanation

To calculate the standard enthalpy of formation (Δ_fH°) for ICl(g), we can use the given dissociation and sublimation enthalpies. Here’s a step-by-step solution:

### Step 1: Write the dissociation reactions
1. **Dissociation of Cl₂(g)**:
\[ \text{Cl}_2(g) \rightarrow 2 \text{Cl}(g) \quad \Delta H_1 = 57.9 \text{ kcal/mol} \]

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