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Assertion : Reduction of ZnO with carbon...

Assertion : Reduction of ZnO with carbon is done at `1100^(@)C`.
Reason : At this temperature, `DeltaG^(@)` is negative and the process is spontaneous.

A

If both assetion and reason are CORRECT, and reason is the CORRECT explanation of the assertion

B

If both assertion and reason are CORRECT, but reason is NOT the CORRECT explanation of the assertion

C

If assertion is CORRECT but reason is INCORRECT

D

If assertion is INCORRECT but reason is CORRECT

Text Solution

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The correct Answer is:
To solve the question, we need to evaluate both the assertion and the reason provided: **Assertion:** Reduction of ZnO with carbon is done at 1100°C. **Reason:** At this temperature, ΔG° is negative and the process is spontaneous. ### Step-by-Step Solution: 1. **Understanding the Assertion:** - The assertion states that the reduction of zinc oxide (ZnO) with carbon occurs at 1100°C. - This is a common temperature used in metallurgy for the reduction of metal oxides, including ZnO. 2. **Understanding the Reason:** - The reason provided states that at this temperature, the Gibbs free energy change (ΔG°) is negative, indicating that the reaction is spontaneous. - A negative ΔG° means that the reaction can proceed without external energy input, which is a criterion for spontaneity. 3. **Referencing the Ellingham Diagram:** - The Ellingham diagram is a graphical representation that shows the stability of metal oxides and the temperature dependence of their Gibbs free energy. - For the reduction of ZnO, we can refer to the Ellingham diagram to confirm that at 1100°C, the ΔG° for the reaction ZnO + C → Zn + CO is indeed negative. 4. **Conclusion:** - Both the assertion and the reason are correct. - The reason correctly explains why the assertion is true: the reduction of ZnO with carbon is spontaneous at 1100°C due to the negative ΔG°. 5. **Final Answer:** - Since both the assertion and the reason are correct, and the reason is the correct explanation of the assertion, the correct option is **Option 1**.
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