Assertion :- `H_(2)S+Cl_(2)rarr2HCl+S`
In the above reaction, Cl has been oxidised to `Cl^(-)` while `S^(-2)` has been reduced to S
Reason :- In a reaction the element whose oxidation number decreases is reduced and the element whose oxidation number increases is oxidised

Options

A. If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion.
B. If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion.
C. If Assertion is True but the Reason is False.
D. If both Assertion & Reason are False.

Answer

To solve the given question, we need to analyze both the assertion and the reason provided. Let's break down the steps systematically.

### Step 1: Write down the reaction
The reaction given in the assertion is:
\[ H_2S + Cl_2 \rightarrow 2HCl + S \]

### Step 2: Determine the oxidation states
Next, we need to assign oxidation states to each element in the reaction:
- In \( H_2S \):
- \( H \) has an oxidation state of +1.
- \( S \) has an oxidation state of -2.

- In \( Cl_2 \):
- \( Cl \) has an oxidation state of 0 (as it is in its elemental form).

- In \( HCl \):
- \( H \) has an oxidation state of +1.
- \( Cl \) has an oxidation state of -1.

- In \( S \):
- \( S \) has an oxidation state of 0.

### Step 3: Identify changes in oxidation states
Now, let's analyze the changes in oxidation states:
- For \( Cl \):
- Changes from 0 (in \( Cl_2 \)) to -1 (in \( HCl \)). This indicates a reduction (gain of electrons).

- For \( S \):
- Changes from -2 (in \( H_2S \)) to 0 (in \( S \)). This indicates an oxidation (loss of electrons).

### Step 4: Evaluate the assertion
The assertion states that:
- Chlorine has been oxidized to \( Cl^- \) while \( S^{2-} \) has been reduced to \( S \).

From our analysis:
- Chlorine is actually reduced (not oxidized).
- Sulfur is oxidized (not reduced).

Thus, the assertion is **false**.

### Step 5: Evaluate the reason
The reason states:
- In a reaction, the element whose oxidation number decreases is reduced, and the element whose oxidation number increases is oxidized.

This statement is **true** based on the definitions of oxidation and reduction.

### Final Conclusion
- The assertion is **false**.
- The reason is **true**.

### Answer
Thus, the final answer is:
- Assertion: False
- Reason: True

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