Geometric stereoisomerism

—> caused by a double/triple bond stereoisomers : compound that have the same structural formula but the arrangement of their atoms in space is different

• only occur in alkenes

—> due to restricted rotation around the double/triple bond

—> does each carbon have at least 1 group in common

—> must be 2 of the same groups ON EACH CARBON!

—> if the 2 groups attached to each carbon atom are the same then use cis/trans

• cis = same side of double bond
• trans = opposite

—> does each carbon atom have 2 different groups

—> if yes then it has E/Z

• E : opposite side
• Z : same side