What happens when Acetaldehyde reacts with Tollen's reagent?

The correct answer is option 1. Produces silver mirror precipitate.

Tollen's reagent is a chemical reagent used to detect the presence of aldehydes. It consists of a solution of silver nitrate (\(AgNO_3\)) in ammonia (\(NH_3\)) which forms the diamminesilver(I) complex ion, \([Ag(NH_3)_2]^+\).

When acetaldehyde (\(CH_3CHO\)) reacts with Tollen's reagent, the following reactions take place.

Oxidation of Acetaldehyde: Acetaldehyde is oxidized to acetic acid (\(CH_3COOH\)).

\(CH_3CHO + H_2O \rightarrow CH_3COOH + 2H^+ + 2e^-\)

Reduction of Tollen's Reagent: The diamminesilver(I) complex is reduced to metallic silver.

\([Ag(NH_3)_2]^+ + e^- \rightarrow Ag + 2NH_3\)

Overall, the reaction can be summarized as: \(CH_3CHO + 2[Ag(NH_3)_2]^+ + 3OH^- \rightarrow CH_3COO^- + 2Ag + 4NH_3 + 2H_2O\)

In this process:

Acetaldehyde (\(CH_3CHO\)) is oxidized to acetic acid (\(CH_3COOH\)). The silver ion (\(Ag^+\)) in the diamminesilver(I) complex is reduced to metallic silver (\(Ag\)), which precipitates out of the solution. The formation of a silver mirror on the inner surface of the reaction vessel is a positive test for the presence of an aldehyde. Therefore, when acetaldehyde reacts with Tollen's reagent, a silver mirror precipitate is produced. So, the correct answer is: 1. Produces silver mirror precipitate.