Despite the limitations of radical chlorination of alkanes, the reaction is still useful for synthesizing certain halogenated compounds. For which of the following compounds does radical monochlorination give a single product?
CH4
2-methylpropane
1-methylcyclopentane
Which one give a single product and what is radical monochlorination?

2-methylpropane

Explanation:

The structure of 2-methylpropane is contrasted with that of propane in the image attached. It is easy to see that 2-methylpropane contains a tertiary carbon atom which forms a stable radical. This stable radical formed will eventually lead to the yield of a single product which is 2-chloro-2-methylpropane. A tertiary radical is the most stable radical and often leads to the formation of a single product.