Optical Isomerism

• Optical Isomerism is a type of Stereoisomerism where molecules have the same molecular formula but a different spatial arrangement of atoms in space
• Optical Isomerism occurs when there is an asymmetrical carbon within an organic molecule known as a chiral centre
• The presence of a chiral centre leads to the presence of two possible isomers that are mirror images of each other
• A Racemic mixture is formed when optical isomers produce a pair of enantiomers in a 1:1 ratio
• Optical Isomerism is a type of stereoisomerism
• It occurs in molecules that have chirality due to the presence of an asymmetrical carbon atom
• Chiral Carbon

  The chiral centre is a carbon atom attached to 4 different groups
• As a result of Optical Isomerism...

  • Two Enantiomers ( non-superimposable mirror images ) are formed
  • Enantiomers that differ only in how the interact with plane polarised light
• Physical properties of Enantiomers

  • Identical Melting point , Boiling point and solubilities
• Enantiomers effect on Plane polarised light

  • Rotate plane polarised light in opposite directions clockwise and anticlockwise
• Racemic Mixture

  A racemic mixture contains equal amounts of both enantiomer
• Racemic Mixture

  Racemates are optically inactive because the rotations of plane polarised light cancel each other out