Question

What happens when (write chemical equation) acetaldehyde is reduced with hydrogen in the presence of Zn/Hg and conc. HCl?

Answer 1

When acetaldehyde is reduced with hydrogen in the presence of Zn/Hg and concentrated HCl, it undergoes a Clemmensen Reduction. The carbonyl group (> C = O) is completely reduced to a methylene group (> CH₂), converting the aldehyde into ethane.

\[\ce{\underset{Acetaldehyde}{CH3CHO} + 4[H] ->[Zn-Hg/conc{.} HCl][] \underset{Ethane}{CH3-CH3} + H2O}\]