Addition of HCN to acetaldehyde in the presence of dilute mineral acid and sodium cyanide forms
Correct answer: B. Acetaldehyde cyanohydrin
- A. Formaldehyde cyanohydrin
- B. Acetaldehyde cyanohydrin
- C. Acetone cyanohydrin
- D. Butanone cyanohydrin
Explanation
When HCN is added to a carbonyl compound like acetaldehyde, a nucleophilic addition reaction occurs, resulting in the formation of a cyanohydrin. The cyanohydrin contains a nitrile (-CN) and a hydroxyl (-OH) group on the same carbon atom. Since acetaldehyde is the carbonyl compound used, the product is acetaldehyde cyanohydrin. The other options involve different starting carbonyl compounds (formaldehyde, acetone, butanone) and are therefore incorrect in this context.
Last updated
About Aldehydes and Ketones
Aldehydes and ketones contain the polar carbonyl group, but aldehydes are generally more readily oxidised and more reactive than ketones. Coverage includes preparation by oxidation or reduction routes, nucleophilic addition of reagents such as hydrogen cyanide and bisulfite, and tests that distinguish aldehydes from ketones.
Practise Aldehydes and Ketones
679 free Aldehydes and Ketones MCQs from Chemistry, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Exams that ask Chemistry questions like this
Chemistry is on 12 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.