Stereoisomerism

E/Z Isomerism

The Pi bond restricts rotation about the C=C bond. The groups attatched to the Carbons of the C=C bond have fixed positions and can rotate from one side of the double bond to the other. 

A molecule has E/Z Isomerism if it follows these 2 rules:

• There is a C=C bond.
• There are 2 different groups attatched to each Carbon atom of the C=C bond.

These are E/Z isomers of Bu-2-ene. In But-2-ene, the 2 Hydrogens can be on the same side as eachother or on oppostie sides of the C=C bond. If they are on the same side of the C=C bond, they are Z isomers but if they are on opposite sides of the C=C bond, then the…