optical isomerism

Define structural isomers

Molecules were the same molecular formula but different structural formula

Define stereo isomers

Molecules were the same structural formula but a different arrangement of atoms in space

Condition for a molecule to not exhibit optical isomerism

No chiral carbon

Define optical isomers

Non-superimposable mirror images of each other

Condition for a molecule/compound exhibit optical isomerism

Must contain a carbon atom bonded to 4 different atoms/groups of atoms

Two optical isomers are called

enantiomers

How do optical isomers differ?

Their effect on plain polarise light is different. They rotate the plane polarise light in equal amounts in opposite directions.

practice drawing optical isomers pg5

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racemic Mixture

Equal amounts of the two enantiomers

optical isomerism have the same chemical properties

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Q: Explain why a racemic mixture is formed when but 2 ene is reacted with HBR

The Carbocation intermediate is planer and the BR ion is equal equally likely attack from above or below the plane leading to equal amounts of both enantiomers