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(a). IF both (A) and (R) are correct and...

(a). IF both (A) and (R) are correct and (R) is the correct explanation of (A).
(b). If both (A) and (R) are correct but (R) is not the correct explanation of (A).
(c). If (A) is correct, but (R) is incorrect.
(d). If (A) is incorrect, but (R) is correct. ltbr. (e) if both (A) and (R) are incorrect.
Q. Assertion (A): Equivalent mass of `KMnO_(4)` is equal to one-fifth of its molecular mass when it acts as oxidising agent in mild basic medium.
Reason (R): Oxidation number of Mn in `KMnO_(4)` is `+7`.

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To solve the question, we need to analyze both the assertion (A) and the reason (R) provided in the statement. ### Step 1: Analyze Assertion (A) Assertion (A) states that the equivalent mass of KMnO4 is equal to one-fifth of its molecular mass when it acts as an oxidizing agent in a mild basic medium. - In a basic medium, KMnO4 (or MnO4^-) gets reduced from an oxidation state of +7 to +6. - The change in oxidation state indicates that 1 electron is involved in the reduction process. - The equivalent weight is calculated as: \[ \text{Equivalent weight} = \frac{\text{Molar mass}}{n} \] where \( n \) is the number of electrons transferred. Here, \( n = 1 \). Thus, the equivalent mass of KMnO4 in a basic medium is equal to its molar mass, not one-fifth of it. Therefore, Assertion (A) is **incorrect**. ### Step 2: Analyze Reason (R) Reason (R) states that the oxidation number of Mn in KMnO4 is +7. - To find the oxidation state of Mn in KMnO4, we can set up the equation: \[ x + 4(-2) = -1 \] where \( x \) is the oxidation state of Mn. Solving this gives: \[ x - 8 = -1 \implies x = +7 \] Thus, the oxidation number of Mn in KMnO4 is indeed +7. Therefore, Reason (R) is **correct**. ### Conclusion - Assertion (A) is incorrect. - Reason (R) is correct. Thus, the correct answer is **(d)**: If (A) is incorrect, but (R) is correct. ---
To solve the question, we need to analyze both the assertion (A) and the reason (R) provided in the statement. ### Step 1: Analyze Assertion (A) Assertion (A) states that the equivalent mass of KMnO4 is equal to one-fifth of its molecular mass when it acts as an oxidizing agent in a mild basic medium. - In a basic medium, KMnO4 (or MnO4^-) gets reduced from an oxidation state of +7 to +6. - The change in oxidation state indicates that 1 electron is involved in the reduction process. - The equivalent weight is calculated as: ...
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