Stereoisomerism
Enantiomers, are also called "optical isomers." Enantiomers are stereoisomers that are like mirror images of each other but can't be turned around or moved so that they are the same, the way a right hand and a left hand of the same person are mirror images of each other. Compounds that are enantiomers to each other have the same physical properties, except for the direction in which they rotate polarized light and how they interact with different optical isomers of other compounds. Pure enantiomers also have optical activity and can be separated only with the use of a chiral agent. An optically active compound shows two forms: D-(+) form and L-(−) form.