3-Methylpent-2-ene (CH3CH=C(CH3)CH2CH3) reacts with Hydrogen Chloride(HCl) forming a major and minor product. Please name the reaction, draw the mechanism for the formation of the major product and briefly explain why there is a major and a minor product.

This is an example of electrophilic addition.(It's easier to explain with the mechanism drawn) The mechanism proceeds by electrophilic attack of the Hydrogen in HCl originating from the double bond in 3-methylpent-2-ene. An intermediate carbocation is formed at the C3 position over the C2 position as tertiary carbocations are more stable than secondary ones. The Chloride ion then attacks the C3+ position forming the major product 3-chloro-3-methylpentane. A minor product also exists as a secondary carbocation can be formed by addition at the C2 position, though this is less favourable.