Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): The nucleophilic addition-elimination reactions of aldehydes with ammonia derivatives require carefully controlled mildly acidic conditions. Reason (R): Mild acid protonates the carbonyl oxygen to increase electrophilicity, but highly acidic conditions protonate the ammonia derivative, destroying i

Step-by-step solution

Assertion (A) is true. The reaction of aldehydes and ketones with ammonia derivatives is acid-catalysed and requires a specific pH range (typically around 3.5) to proceed efficiently. Reason (R) is also true and correctly explains the Assertion. In a mildly acidic medium, the carbonyl oxygen gets protonated, which increases the electrophilic character of the carbonyl carbon, facilitating the nucleophilic attack by the ammonia derivative. However, if the medium is too acidic (low pH), the basic ammonia derivative it