Chemistry · Alkyl Halides and Amines

The major product is 2-pentene because it is the most stable alkene formed after carbocation rearrangement and follows Zaitsev's rule. The reaction proceeds through an E1 mechanism involving a carbocation intermediate and rearrangement.

1-Pentene: This would be the product if elimination occurred at the primary carbon, but this is less favored due to the instability of the primary carbocation and the tendency to form more substituted alkenes.

This option is correct. The major product of the acid-catalyzed dehydration of 3-pentanol is 2-pentene, specifically the E-isomer (trans-isomer). Dehydration leads to the formation of a more stable carbocation, followed by elimination, forming the most stable alkene according to Zaitsev's rule.

2-Methylbutane is an alkane and not an alkene. Dehydration of alcohols results in the formation of alkenes, not alkanes.

3-Methylbutane is incorrect because it is an alkane and does not reflect the dehydration process which produces alkenes, not alkanes.