Which of the following reactions taking place in the blast furnace during extraction of iron is endothermie ?

Options

A. `CaCO_(3) rarr CaO + CO_(2)`
B. `2C + O_(2) rarr 2 CO`
C. `C + O_(2) rarr CO_(2)`
D. `Fe_(2) O_(3) + 3CO rarr 2Fe + 3CO_(2)`

Answer

To determine which of the reactions taking place in the blast furnace during the extraction of iron is endothermic, we need to analyze the nature of the reactions involved.

### Step-by-Step Solution:

1. **Understand Endothermic Reactions**:
- An endothermic reaction is one that absorbs heat from its surroundings. This means that the enthalpy change (ΔH) for the reaction is positive.

2. **Identify Reactions in the Blast Furnace**:
- The main reactions that occur in the blast furnace during the extraction of iron include:
- The formation of carbon monoxide from carbon and oxygen:
\[ C + O_2 \rightarrow CO \quad (\text{exothermic}) \]
- The formation of carbon dioxide from carbon and oxygen:
\[ C + O_2 \rightarrow CO_2 \quad (\text{exothermic}) \]
- The reduction of iron oxide (Fe2O3) by carbon monoxide to produce iron:
\[ Fe_2O_3 + 3CO \rightarrow 2Fe + 3CO_2 \quad (\text{exothermic}) \]

3. **Identify the Endothermic Reaction**:
- Among these reactions, the calcination of calcium carbonate (CaCO3) is a reaction that is endothermic:
\[ CaCO_3 \rightarrow CaO + CO_2 \quad (\text{endothermic}) \]
- This reaction requires heat to proceed, thus it absorbs heat from the surroundings.

4. **Conclusion**:
- Therefore, the endothermic reaction taking place in the blast furnace during the extraction of iron is the decomposition of calcium carbonate (option 1).

### Final Answer:
The endothermic reaction is the decomposition of calcium carbonate (CaCO3).

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