Why Alkanes Can’t Do Geometrical Isomerism: Find Out!

Alkenes have carbon-carbon sigma bonds allowing free rotation, unlike pi bonds formed by lateral overlap of 2P orbitals, which restrict rotation. This restriction leads to the existence of stereoisomers, specifically cis and trans isomers, in alkenes with two different groups.

What type of bond in alkenes allows for free rotation around the carbon-carbon bond axis?

• Double bond

• Triple bond

• Sigma bond

• Pi bond

How is a pi bond formed in alkenes?

• By the overlap of s orbitals

• By the overlap of p orbitals

• By the lateral overlap of 2P orbitals

• By the overlap of d orbitals

Why is free rotation around a pi bond restricted?

• Because pi bonds are formed by head-on overlap of orbitals

• Because pi bonds are formed by lateral overlap of orbitals

• Because pi bonds are weaker than sigma bonds

• Because pi bonds are stronger than sigma bonds

What are the two types of stereoisomers that can exist in alkenes with two different groups?

• Cis and trans isomers

• Alpha and beta isomers

• E and Z isomers

• R and S isomers

Which of the following is true about cis and trans isomers?

• They are only found in alkanes

• They are identical in structure

• They have different physical and chemical properties

• They can freely rotate around the pi bond