Cis-Trans Isomerism in Organic Compounds

Which compounds exhibit cis-trans isomerism?

A. 2-octene

B. 2-methyl-1-butene

Answer:

Cis-trans isomerism is possible for compounds that have a carbon-carbon double bond. In this case, it is possible for 2-octene, where the cis isomer will have the methyl groups on the same side of the double bond. This is not possible for 2-methyl-1-butene.

Cis-trans isomerism, also known as geometric isomerism, is possible in molecules that have a carbon-carbon double bond, where the same types of atoms or groups are attached to each other in the same order, but the geometries of the two molecules differ. The two compounds in question are 2-octene and 2-methyl-1-butene.

2-Octene: The second carbon atom in the chain has a double bond which allows for cis-trans isomerism. Therefore, cis-trans isomerism is possible for 2-octene. The cis isomer will have the methyl groups on the same side of the double bond.

2-methyl-1-butene: In this case, a methyl group is linked to the first carbon atom forming a double bond. Consequently, cis-trans isomerism is not possible for this compound, since it doesn't have two different groups at both ends of the double bond. Thus, the correct answer is that cis-trans isomerism is possible for 2-octene but not for 2-methyl-1-butene.

For further understanding of cis-trans isomerism, you can refer to additional resources on the topic.