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JEE Main202330 Jan 2023Evening ShiftChemistryHydrocarbonsActual

Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R. Assertion A: can be easily reduced using Zn - Hg / HCl to Reason R: Zn - Hg / HCl is used to reduce carbonyl group to – CH 2 – group. In the light of the above statements, choose the correct answer from the options given below:

Options

  1. AA is false but R is true
  2. BA is true but R is false
  3. CBoth A and R are true but R is not the correct explanation of A
  4. DBoth A and R are true and R is the correct explanation of A

Correct answer

A. A is false but R is true

Step-by-step solution

Clemmensen reduction: The carbonyl group of aldehydes and ketones is reduced to CH 2 group on treatment with zinc-amalgam and concentrated hydrochloric acid. The acid sensitive alcohol group reacts with HCl , hence Clemmenson reduction is not suitable for above conversion. So, assertion is false but reason is true.

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