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8.1. Aldehydes and ketones — Chemistry STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceChemistry8.1. Aldehydes and ketones1 Mark
MCQ
Assertion : Benzaldehyde is more reactive than ethanol towards nucleophilic attack.
Reason : The overall effect of $-I$ and $+ R$ effect of phenyl group decreases the electron density on the carbon atom of $> C = O$ group in benzaldehyde
  • A
    If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
  • B
    If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
  • C
    If the Assertion is correct but Reason is incorrect.
  • ✓
    If both the Assertion and Reason are incorrect.
✓

Answer

Correct option: D.
If both the Assertion and Reason are incorrect.
d
Benzaldehyde is less reactive than ethanol towards nucleophilic attack. The combined effect of $-I$ and $+R$ effect of phenyl group is electron donating which increases the electron density on the carbon atom of the $> C = O$ in benzaldehyde.

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