Lesson eLearning

When benzaldehyde (C6H5CHO) is reduced with sodium borohydride in ethanol, which product is obtained?

easy MCQ 1 mark Class 12 · Chemistry · Aldehydes Ketones and Carboxylic Acids
  1. benzyl alcohol
  2. phenol
  3. benzoic acid
  4. benzyl cyanide
Answer
benzyl alcohol

The correct answer is benzyl alcohol — Step 3: Verify that no further oxidation or rearrangement occurs under these conditions.

Step-by-step solution

  1. Step 1: Recognise that NaBH4 is a mild reducing agent that reduces aldehydes to primary alcohols.
  2. Step 2: Apply this to benzaldehyde to obtain benzyl alcohol, CH3CH2OH attached to the phenyl ring.
  3. Step 3: Verify that no further oxidation or rearrangement occurs under these conditions.
Common mistake: Confusing the product with phenol or benzoic acid

Concept tested: Reduction of aldehydes

Published · How this solution was prepared and checked

← All Aldehydes Ketones and Carboxylic Acids questions