Final answer:
Treatment of an aldehyde or ketone with organolithium or Grignard reagent and subsequent addition of water produces a secondary or tertiary alcohol, respectively, after the nucleophilic addition of the organometallic compound to the carbonyl group followed by protonation.
Step-by-step explanation:
When treating an aldehyde or ketone with an organolithium or Grignard reagent followed by water, the result is the formation of a secondary or tertiary alcohol, respectively. These reagents are strong nucleophiles that attack the electrophilic carbon of the carbonyl group (C=O) in aldehydes and ketones. The carbon-oxygen double bond is broken, and a new carbon-oxygen single bond is formed when the organometallic reagent adds to the carbonyl group, followed by a protonation step with water to yield the respective alcohols.
In the case of aldehydes, the nucleophilic addition of the organometallic reagent forms a secondary alcohol after protonation with water. For ketones, this reaction results in the formation of a tertiary alcohol. The process is widely used in synthetic organic chemistry for the synthesis of complex alcohols from simpler carbonyl precursors.