Optical isomerism

• Optical isomers are also reffered to as enantiomers
• optical isomers are moecules with the same structural formula but form mirror images of each other
• optical isomers only form when molecules have chiral carbons
• A chiral carbon is a carbon with 4 different groups attached to it
• an optical isomer rotates plane polarised light clockwise or anti-clockwise depending on the isomer
• Different enantiomers of the same substance rotate plane polarised light by the same amount but in opposite directions
• Plane polarised light will not be affected by a 50:50 mixture of each enantiomer and the solution is considered optically inactive
• a racemic mixture has equal amounts of both enantiomers so there is no net rotation of plane polarised light
• The test for an optical isomer:

  Shine plane polarised light through a solution of that isomer and observe if there is any rotation