Question

Draw the cis and trans isomers of 2-butene, ch3chchch3. show all hydrogen atoms.

Answer 1

In general chemistry, isomers are two or more elements that have the same number of protons but differ in mass number. In organic chemistry, the compounds are cis or trans isomers if they have the same chemical formula, but differ in the placement of functional groups based on molecular geometry. Cis isomer is when two like functional groups are on the same side of the molecules, while trans isomer is when the like functional groups are on opposite sides. 

The cis-trans isomers are shown in the picture. As you can see, in the cis isomer, the methane functional group are both in the same side. Same as well with the hydrogen atoms. On the other hand, these functional groups are opposite to each other in the trans isomer.

Answer 2

The cis isomer is formed when the methyl groups are present on the same side of carbon-carbon double bond and trans isomer is formed when methyl groups are placed on opposite sides of the carbon-carbon double bond. (Refer to the structures in the attached image)

Further explanation:

Isomers are the molecules that have the same molecular formula but different structures. The two major forms of isomers are as follows:

1. Structural or constitutional isomers:

These isomers differ from each other in terms of connectivity of the constituent atoms. For example, propanol and methoxyethane are structural isomers of each other.

2. Stereoisomers:

These isomers have the same connection of atoms but with different geometries. 1,2-disubstituted ethenes are examples of stereoisomers.

Cis and trans are the two types of stereoisomers. Both these forms have different geometries and therefore also known as geometrical or configurational isomers.

In the cis-form, the same functional groups are present on the same side of the carbon-carbon double bond. But if the same functional groups are present on the opposite side of the carbon-carbon double bond, the resulting isomer is called the trans-form. These isomers have the identical molecular formula but a different arrangement of functional groups around the carbon atom.

2-butene $\left({{\text{C}}{{\text{H}}_3}{\text{CHCHC}}{{\text{H}}_3}}\right)$ shows geometrical isomerism. When methyl $\left({-{\text{C}}{{\text{H}}_3}}\right)$ groups are present on the same side of carbon-carbon double bond, that isomer is called the cis-form. But when both methyl $\left({-{\text{C}}{{\text{H}}_3}}\right)$ groups are present on opposite sides of the carbon-carbon double bond, it results in the formation of trans-isomer. (Refer to the structures in the attached image)

Learn more:

1. The name of the hydrocarbon: brainly.com/question/35515462

2. Draw the stereoisomers of 1,2-difluoro-1,2-dimethylcyclopentane: brainly.com/question/8803065

Answer details:

Grade: High School

Subject: Chemistry

Chapter: Stereochemistry

Keywords: 2-butene, isomers, stereoisomers, structural isomers, same side, different side, functional groups, cis, trans, structure, geometries, different, same, methyl, CH3CHCHCH3, CH3, carbon, double bond.