Ethene reacts with hydrogen bromide to give

When ethene (C2H4) reacts with hydrogen bromide (HBr), it undergoes an addition reaction to form a haloalkane. Specifically, the hydrogen (H) of HBr adds to one carbon of the ethene, and the bromine (Br) adds to the other carbon, resulting in the formation of a monobromoalkane. The correct answer is therefore: - CH3CH2Br (or C2H5Br) (CH2Br2) is incorrect as it represents dibromomethane, which is not the expected product of the reaction. (CH3CHBr2) is incorrect as it represents dibromoethane, which is also not the expected product of the reaction. (C2H2Br2) is incorrect as it represents 1,2-dibromoethene, which is a dihaloalkene and also not the expected product of the reaction. Therefore, the correct answer is.