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Assertion : Cr^(2+) is reducing and Mn^(...

Assertion : `Cr^(2+)` is reducing and `Mn^(3+)` is oxidising.
Reason : `Cr^(2+)` and `Mn^(3+)` have `d^4` configuration.

A

If both assertion and reason are true and reason is the correct explanation of assertion.

B

If both assertion and reason are true and reason not is the correct explanation of assertion.

C

If assertion is trun but reason is false.

D

If both assertion and reason are false.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question, we need to analyze both the assertion and the reason provided. ### Step 1: Analyze the Assertion The assertion states that `Cr^(2+)` is a reducing agent and `Mn^(3+)` is an oxidizing agent. - **Cr^(2+) as a Reducing Agent**: - Chromium in the +2 oxidation state has the electronic configuration of `[Ar] 3d^4`. It can easily lose an electron to form `Cr^(3+)`, which has a more stable half-filled configuration of `3d^3`. This tendency to lose an electron indicates that `Cr^(2+)` acts as a reducing agent. - **Mn^(3+) as an Oxidizing Agent**: - Manganese in the +3 oxidation state has the electronic configuration of `[Ar] 3d^4`. It can gain an electron to form `Mn^(2+)`, which has a more stable half-filled configuration of `3d^5`. This tendency to gain an electron indicates that `Mn^(3+)` acts as an oxidizing agent. ### Conclusion for Step 1: The assertion is correct because `Cr^(2+)` does act as a reducing agent and `Mn^(3+)` does act as an oxidizing agent. ### Step 2: Analyze the Reason The reason states that both `Cr^(2+)` and `Mn^(3+)` have a `d^4` configuration. - **Electronic Configurations**: - `Cr^(2+)`: `[Ar] 3d^4` - `Mn^(3+)`: `[Ar] 3d^4` While it is true that both ions have a `d^4` configuration, this does not fully explain why `Cr^(2+)` is reducing and `Mn^(3+)` is oxidizing. The stability of their respective oxidation states is influenced more by the stability of their electronic configurations rather than just the `d^4` configuration itself. ### Conclusion for Step 2: The reason is not a valid explanation for the assertion, even though both the assertion and the reason are true. ### Final Conclusion: - The assertion is correct. - The reason is correct but does not explain the assertion. - Therefore, the correct option is that both the assertion and reason are true, but the reason does not explain the assertion. ### Summary of the Solution: 1. **Assertion**: `Cr^(2+)` is a reducing agent because it can lose an electron to become more stable as `Cr^(3+)`. 2. **Assertion**: `Mn^(3+)` is an oxidizing agent because it can gain an electron to become more stable as `Mn^(2+)`. 3. **Reason**: While both ions have a `d^4` configuration, this alone does not explain their respective reducing and oxidizing behaviors.
To solve the question, we need to analyze both the assertion and the reason provided. ### Step 1: Analyze the Assertion The assertion states that `Cr^(2+)` is a reducing agent and `Mn^(3+)` is an oxidizing agent. - **Cr^(2+) as a Reducing Agent**: - Chromium in the +2 oxidation state has the electronic configuration of `[Ar] 3d^4`. It can easily lose an electron to form `Cr^(3+)`, which has a more stable half-filled configuration of `3d^3`. This tendency to lose an electron indicates that `Cr^(2+)` acts as a reducing agent. ...
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