How much heat is evolved by the preparation of 100 gm of iron by the following reaction ?
`2Al(s)+Fe_(2)O_(3)(s)to2Fe(s)+Al_(2)O_(3)(s) , Delta_(r )H=-202.6` kcal/mol

Explanation

To determine how much heat is evolved by the preparation of 100 grams of iron from the given reaction, we can follow these steps:

### Step 1: Understand the Reaction and Given Data
The reaction is:
\[ 2 \text{Al}(s) + \text{Fe}_2\text{O}_3(s) \rightarrow 2 \text{Fe}(s) + \text{Al}_2\text{O}_3(s) \]
The enthalpy change (\( \Delta_r H \)) for the reaction is given as \( -202.6 \) kcal for the formation of 2 moles of iron.

### Step 2: Calculate Heat Evolved for 1 Mole of Iron
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