Question

Question #d6c0e

Answer 1

Only D) CHCl=CHCl exhibits cis-trans isomerism.

The condition for cis-trans isomerism in an alkene is:

• The carbon atoms at each end of the double bond must both have different groups attached to them.

In A) each carbon has two identical groups (H atoms).

In B) the left hand carbon has two identical groups (H atoms), and the right hand carbon has two identical groups (Cl atoms).

In C) the left hand carbon has two identical groups (Br atoms).

In E) the left hand carbon has two identical groups (methyl groups).

In D) the left hand carbon has two different groups (H and Cl), and the right hand carbon has two different groups (H and Cl)

So only D) CHCl=CHCl can exhibit cis-trans isomerism.