Which of the following compounds will exhibit cis-trans (geometrical) isomerism ?1-Butanol2-Butene2-Butanol2-Butyne

Geometrical isomerism (also known as cis-trans isomerism) occurs when there is restricted rotation in a molecule, which is typically due to the presence of a double bond or a ring structure.

Among the given options:

1. 1-Butanol: This compound does not have a double bond or a ring structure, so it cannot exhibit geometrical isomerism.

2. 2-Butene: This compound has a double bond between the second and third carbon atoms, so it can exhibit geometrical isomerism.

3. 2-Butanol: This compound does not have a double bond or a ring structure, so it cannot exhibit geometrical isomerism.

4. 2-Butyne: This compound has a triple bond, which does not allow for cis-trans isomerism.

So, the correct answer is 2-Butene.