Question

Classify each transformation as substitution, elimination, or addition.

a.

b.

Short answer

Answer

1. Elimination reaction
2. Addition reaction

Step-by-step solution

Step-by-Step SolutionStep 1: Substitution Reaction

The reactions that involve the replacement/substitution of a group or atom by another is termed substitution reaction.

Addition and Elimination Reactions

The addition of atoms or groups of atoms to a substrate is termed an addition reaction, and the removal or elimination of atoms/groups of atoms from a substrate is termed an elimination reaction.

Classifying the given reactions

a. The reaction ‘a’ involves the elimination of ${\mathrm{H}}_2\mathrm{O}\left(\mathrm{H}+\mathrm{OH}\right)$from the starting material leading to the formation of a pi bond in the product.

Elimination reaction in a.

Therefore, the given reaction is an elimination reaction.

b. The given reaction involves the addition of hydrogen and a hydroxyl group to the carbonyl carbon leading to the conversion of the pi bond to two sigma bonds.

Addition reaction in b.

The given reaction is an addition reaction.