Q. During the reaction between carbonyl compounds with ammonia derivatives, a proper $pH$ is required. Select the correct reasons.

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To increase positive charge on the $C$ atom of $(C=O)$ group for the better attack of nucleophilic centre of ammonia derivative, a small amount of acid is needed.

With excess of acid, ammonia derivatives form their salts and act as strong nucleophiles.

With excess of acid, ammonia derivatives form their salts and cannot act as nucleophiles.

The proper pH required for these reactions is nearly $3.5$.

Solution:

Correct answer is (a) To increase positive charge on the $C$ atom of $(C=O)$ group for the better attack of nucleophilic centre of ammonia derivative, a small amount of acid is needed.Correct answer is (c) With excess of acid, ammonia derivatives form their salts and cannot act as nucleophiles.Correct answer is (d) The proper pH required for these reactions is nearly $3.5$.

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