What halide would undergo dehydrohalogenation to give 2-pentene as a pure product? answers?

3-chloropentane.

Explanation:

Hello, in this case, an elimination chemical reaction must be considered since the reactant is an alkyl halide, in such a way, we must conserve the main 5-carbon chain and look for the suitable position of the to-eliminate halogen which is chlorine. Now, on the attached picture, you will see that such halide is 3-chloropentane as long as its dehydrohalogenation is carried out in a strong basic media provided by potassium hydroxide (KOH) and using ethanol as a solvent to allow the 2-pentene to be yielded in addition to the side products such as hydrochloric acid or potassium chloride.

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