Question

Alcoholic solution of $\mathrm{KOH}$ is a specific reagent for

• A. Dehydration
• B. Dehalogenation
• C. Dehydrogenation
• D. Dehydrohalogenation

Answer 1

The correct option is D

Dehydrohalogenation

The explanation for the correct answer

Option (D) Dehydrohalogenation.

• Alcoholic solution of $\mathrm{KOH}$ is a specific reagent for Dehydrohalogenation of haloalkane and results in the formation of Alkenes.
• Reaction mechanism:

• In the above reaction of bromine and beta, hydrogen is eliminated to form ethene.

The explanation for incorrect answers

(A) Dehydration:

• Dehydration is the process of removal of water from the reactant, alcoholic $\mathrm{KOH}$eliminates one molecule of halogen acid to form alkene hence, option A is incorrect.

(B) Dehalogenation

• Dehalogenation is the process of removal of halogen from the alkane derivative. Hence, option b is incorrect.

(C) Dehydrogenation

• Dehydrogenation is the process by which hydrogen is removed from an organic compound to form a new chemical compound, since in the reaction halogen is removed, therefore option c is incorrect.

Alcoholic solution of $\mathrm{KOH}$ is a specific reagent for dehydrohalogenation, option (D) is the correct answer.