Is CH3CH=CHCOOH compound exist as cis-trans isomers or does not, explain your answer

Answer 1

The compound CH3CH=CHCOOH, which is but-2-enoic acid (also known as crotonic acid), can indeed exhibit cis-trans isomerism (geometric isomerism).

Cis-trans isomerism occurs when there is restricted rotation around a double bond and when there are different substituents attached to the carbon atoms involved in the double bond.

In the structure CH3CH=CHCOOH, we have a double bond between the second carbon (C2) and the third carbon (C3). The groups attached to these carbons are as follows:

• For C2: the groups are CH3 (methyl) and H (hydrogen).
• For C3: the groups are H (hydrogen) and COOH (carboxylic acid).

Because the groups attached to the double-bonded carbons (C2 and C3) are different, the compound can exist in two different geometrical forms based on the relative positions of the substituents:

1. Cis isomer: The hydrogen atom on C3 and the carboxylic acid group (COOH) are on the same side of the double bond.
2. Trans isomer: The hydrogen atom on C3 and the carboxylic acid group (COOH) are on opposite sides of the double bond.

Therefore, CH3CH=CHCOOH can exist as cis and trans isomers, hence it demonstrates cis-trans isomerism.