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In the following questions, a statement ...

In the following questions, a statement of assertion (A) is following by a statement of reason (R )
A : primary alkyl halides on oxidation with DMSO gives aldehydes.
R : DMSO is used as polar aprotic solvent .

A

If both Assertion & Reason are 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)

Text Solution

AI Generated Solution

The correct Answer is:
### Step-by-Step Solution 1. **Understanding the Assertion (A)**: The assertion states that primary alkyl halides, when oxidized with DMSO (Dimethyl Sulfoxide), yield aldehydes. - **Explanation**: Primary alkyl halides have the general structure R-CH2-X, where X is a halogen (like Cl, Br, etc.). When these compounds undergo oxidation, the halogen is replaced, leading to the formation of an aldehyde (R-CHO). 2. **Understanding the Reason (R)**: The reason states that DMSO is used as a polar aprotic solvent. - **Explanation**: A polar aprotic solvent is one that has a significant dipole moment but does not have acidic hydrogen atoms. DMSO has a polar structure due to the presence of the sulfur and oxygen atoms, which allows it to dissolve a wide range of polar and ionic compounds without donating protons (H+). 3. **Reaction Mechanism**: - When a primary alkyl halide reacts with DMSO in the presence of a base, the base abstracts the halogen (X) from the alkyl halide, forming a carbocation intermediate. - The DMSO then stabilizes this intermediate, allowing for the formation of an aldehyde through further oxidation. 4. **Conclusion**: Both the assertion and the reason are correct. However, the reason does not adequately explain the assertion. The assertion is true because primary alkyl halides can be oxidized to aldehydes using DMSO, and the reason is true because DMSO is indeed a polar aprotic solvent. Therefore, the correct answer is that both statements are true, but the reason is not the correct explanation for the assertion. ### Final Answer The correct option is **B**: Both A and R are true, but R is not the correct explanation of A.
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