Addition of Br2 to alkenes yields which type of product?

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Multiple Choice

Addition of Br2 to alkenes yields which type of product?

When bromine adds to an alkene, the double bond is broken and a bromine atom attaches to each of the former double-bond carbons. This forms a vicinal dihalide, specifically a 1,2-dibromoalkane, because the two bromine atoms end up on the two adjacent carbons. The mechanism involves a bromonium ion intermediate and anti addition, so the Br atoms come from opposite faces. This is neither an alkane nor an alcohol, and the double bond is consumed in forming the two C–Br bonds. Hence the product is a 1,2-dibromoalkane.

When bromine adds to an alkene, the double bond is broken and a bromine atom attaches to each of the former double-bond carbons. This forms a vicinal dihalide, specifically a 1,2-dibromoalkane, because the two bromine atoms end up on the two adjacent carbons. The mechanism involves a bromonium ion intermediate and anti addition, so the Br atoms come from opposite faces. This is neither an alkane nor an alcohol, and the double bond is consumed in forming the two C–Br bonds. Hence the product is a 1,2-dibromoalkane.

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