Which of the following undergoes "Cannizzaro reaction" ?
Correct answer: A. Benzaldehyde
- A. Benzaldehyde
- B. Acetone
- C. Benzophenone
- D. Benzyl alcohol
Explanation
OPTION A: Aldehydes that have no a -hydrogen atoms undergo Cannizzaro's reaction. It is a disproportionation (self-oxidation-reduction) reaction. Two molecules of the aldehyde are involved, one molecule is converted into the corresponding alcohol (the reduced product) and the other into the acid in the salt form (the oxidation product). The reaction is carried out with a 50 percent aqueous solution of sodium hydroxide at room temperature. Hence, A is the correct option. OPTION B: In order to perform the Cannizzaro reaction, there must not be any alpha hydrogen, since acetone contains alpha hydrogen that is why acetone cannot undergo the Cannizzaro reaction. OPTION C: Benzophenone is a ketone and donot undergo a Cannizzaro reaction. OPTION D: Read option A.
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.