Engineering
Chemistry
Nucleophilic addition
Question

Statement-1 : Aldehyde is more reactive than ketone toward nucleophilic attack.
Statement-2 : Due to less +I effect and less steric hinderance in aldehyde it is more reactive than ketone.

Statement-1 is false, statement-2 is true.

Statement-1 is true, statement-2 is true and statement-2 is correct explanation for statement-1.

Statement-1 is true, statement-2 is false.

Statement-1 is true, statement-2 is true and statement-2 is NOT the correct explanation for statement-1.

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Solution

Both statements are true, and Statement-2 is the correct explanation for Statement-1.

Aldehydes (R-CHO) are more reactive than ketones (R-CO-R') towards nucleophilic addition. This is primarily due to two factors explained in Statement-2:

1. Steric Hindrance: The carbonyl carbon in an aldehyde is less crowded, being attached to one R group and one H atom, making it more accessible to a nucleophile compared to a ketone's carbon, which is attached to two bulkier R groups.

2. Electronic Effect (+I effect): Alkyl groups are electron-donating. A ketone has two electron-donating groups, which increase electron density on the carbonyl carbon, making it less electrophilic (and thus less reactive). An aldehyde has only one such group, so its carbon is a better electrophile.

Final Answer: Statement-1 is true, statement-2 is true and statement-2 is correct explanation for statement-1.