A : When `Cu_(2)S` is converted into `Cu^(++)" & " SO_(2)`, then equivalent weight of `Cu_(2)S` will be M/8 (M = Mol. wt. of `Cu_(2)S`)
R : `Cu^(+)` is converted `Cu^(++)`, during this one electrons is lost.

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark (1).
B. If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark (2).
C. If Assertion is true statement but Reason is false, then mark (3).
D. If both Assertion and Reason are false statements, then mark (4).

Answer

To solve the problem, we need to analyze both the assertion and the reason provided in the question. Let's break it down step by step.

### Step 1: Understanding the Reaction
The reaction given is:
\[ \text{Cu}_2\text{S} + \text{O}_2 \rightarrow \text{Cu}^{2+} + \text{SO}_2 \]

### Step 2: Determine Oxidation States
- In Cu₂S, the oxidation state of Cu is +1 and that of S is -2.
- In Cu²⁺, the oxidation state of Cu is +2.
- In SO₂, the oxidation state of S is +4.

### Step 3: Calculate Change in Oxidation States
- For Copper (Cu):
- Change from +1 (in Cu₂S) to +2 (in Cu²⁺):
\[ \Delta \text{Oxidation State} = +2 - (+1) = +1 \]
- Since there are 2 Cu atoms, the total change for Cu is:
\[ 2 \times (+1) = +2 \]

- For Sulfur (S):
- Change from -2 (in Cu₂S) to +4 (in SO₂):
\[ \Delta \text{Oxidation State} = +4 - (-2) = +6 \]

### Step 4: Total Change in Oxidation State
- Total change in oxidation state for the reaction:
\[ \text{Total Change} = +2 \, (\text{from Cu}) + +6 \, (\text{from S}) = +8 \]

### Step 5: Calculate Equivalent Weight
- The equivalent weight is given by the formula:
\[ \text{Equivalent Weight} = \frac{\text{Molecular Weight}}{\text{Total Change in Oxidation State}} \]
- If M is the molecular weight of Cu₂S, then:
\[ \text{Equivalent Weight} = \frac{M}{8} \]

### Conclusion on Assertion
The assertion states that the equivalent weight of Cu₂S when converted into Cu²⁺ and SO₂ is \( \frac{M}{8} \). This is correct based on our calculations.

### Conclusion on Reason
The reason states that Cu⁺ is converted to Cu²⁺, losing one electron. While this is true, it does not fully explain the assertion because it ignores the change in oxidation state of sulfur. Therefore, both the assertion and reason are correct, but the reason is not the correct explanation for the assertion.

### Final Answer
The correct option is that both assertion and reason are correct, but the reason is not the correct explanation of the assertion.

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