Assertion : `PbSiF_(6)+H_(2)SiF_(6)+` gelatine is taken as electrolyte in electrolytic refining of lead.
Reason : Discharge potential of `Pb^(2+)` is less than `H^(+)`.

Options

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

Answer

To solve the question regarding the assertion and reason provided, we will analyze both statements step by step.

### Step 1: Understand the Assertion
The assertion states that "PbSiF6 + H2SiF6 + gelatine is taken as electrolyte in electrolytic refining of lead."

- **Explanation**: In electrolytic refining, an electrolyte is required to facilitate the movement of ions. In this case, PbSiF6 (lead fluorosilicate) and H2SiF6 (hexafluorosilicic acid) mixed with gelatine are used as electrolytes. This mixture helps in the purification of lead by allowing lead ions to migrate towards the cathode where they are deposited as pure lead.

### Step 2: Understand the Reason
The reason states that "Discharge potential of Pb²⁺ is less than H⁺."

- **Explanation**: The discharge potential refers to the tendency of ions to be reduced (gain electrons) at the cathode during electrolysis. A lower discharge potential means that the ion is more likely to be reduced. In this case, if the discharge potential of Pb²⁺ is indeed less than that of H⁺, it would mean Pb²⁺ would be preferentially discharged over H⁺. However, this statement is incorrect because the discharge potential of Pb²⁺ is actually higher than that of H⁺, meaning H⁺ is discharged preferentially.

### Step 3: Evaluate the Statements
- The assertion is correct as the electrolytes mentioned are indeed used in the electrolytic refining of lead.
- The reason is incorrect because the discharge potential of Pb²⁺ is greater than that of H⁺, which contradicts the reason provided.

### Conclusion
Based on the analysis:
- The assertion is correct.
- The reason is incorrect.

Thus, the correct option is **Option 3**: Assertion is correct, reason is incorrect.

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