The `Delta H^@` for the reaction
`H_2(g) + I_2(g) to 2HI(g)`
is +53.6 kJ. Mention whether the reaction is exothermic or endothermic and calculate the standard heat of formation of HI.

Explanation

To solve the problem step by step, we will first determine whether the reaction is exothermic or endothermic based on the given enthalpy change (ΔH°) and then calculate the standard heat of formation of HI.

### Step 1: Determine if the reaction is exothermic or endothermic
The given reaction is:
\[ \text{H}_2(g) + \text{I}_2(g) \rightarrow 2\text{HI}(g) \]
The enthalpy change (ΔH°) for this reaction is +53.6 kJ.

- If ΔH° is positive, the reaction absorbs heat from the surroundings, indicating that it is an **endothermic reaction**.
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