Practicing Success

Target Exam

CUET

Subject

Chemistry

Chapter

Organic: Haloalkanes and Haloarenes

Question:

Case: Read the passage and answer the questions

There are several methods to prepare halo alkanes and haloarenes. One of the methods is to prepare from alcohol. The hydroxyl group of an alcohol is replaced by halogen on reaction with concentrated halogen acids, phosphorus halides or thionyl chloride. The halo alkanes are prepared by treating alkane with a limited amount of halogen in presence of halogen carrier and sunlight or heat. Adding hydrogen halide to alkene also results in the formation of halo alkanes. Haloarenes are prepared from hydrocarbons by electrophilic substitution and amines by Sandmeyer’s reaction.

Which reagent will you use for the following reaction?

CH3CH2CH2CH3 → CH3CH2CH2CH2Cl + CH3CH2CHClCH3

Options:

Cl2 /UV light

NaCl + H2SO4

Cl2 gas in dark

None of these

Correct Answer:

Cl2 /UV light

Explanation:

Cl2​/UV light free radical substitution mono-chlorinated isomeric products.