What is the product when an alkane is treated with X2 under UV light (slow reaction)?

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Multiple Choice

What is the product when an alkane is treated with X2 under UV light (slow reaction)?

Photochemical halogenation of alkanes proceeds through a radical chain mechanism. The UV light cleaves the X–X bond to form halogen radicals (X•). A halogen radical abstracts a hydrogen from the alkane, giving HX and an alkyl radical. The alkyl radical then reacts with another X2 molecule to produce the haloalkane and regenerate the halogen radical, continuing the cycle. The overall result is substitution of a C–H bond by a C–X bond, so the main product is a haloalkane. This is a radical substitution process, not an alkene-forming or alcohol-forming reaction.

Photochemical halogenation of alkanes proceeds through a radical chain mechanism. The UV light cleaves the X–X bond to form halogen radicals (X•). A halogen radical abstracts a hydrogen from the alkane, giving HX and an alkyl radical. The alkyl radical then reacts with another X2 molecule to produce the haloalkane and regenerate the halogen radical, continuing the cycle. The overall result is substitution of a C–H bond by a C–X bond, so the main product is a haloalkane. This is a radical substitution process, not an alkene-forming or alcohol-forming reaction.

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