Reaction of an alkyl halide with alcoholic potassium hydroxide gives mainly
- A. an alcohol
- B. an alkane
- C. a carboxylic acid
- D. an alkene, by elimination of hydrogen halide
Explanation
In ethanol the hydroxide ion acts as a base rather than as a nucleophile, removing a hydrogen from the carbon next to the one bearing the halogen, so a double bond forms and the hydrogen halide is eliminated. Heat favours this route as well. The contrast with aqueous conditions, which give the alcohol, is the essential comparison in this topic.