This section deals with one of the physical properties of enantiomers. Most of the chemical and physical properties of an enantiomeric pair are identical. They will have the same boiling points, melting points, densities, indices of refraction, heats of formation, etc. One difference, however, is each isomer's effect on polarized light .
Polarized light is light with an electric field that oscillates in only one plane.
It is obtained by passing light through a polarizer like a Nicol prism. Passing this polarized light through another polarizer perpendicular to the plane of the light will result in no light passing through- a dark field . If polarized light is passed through one enantiomer of a chiral substance, the plane of the light emerging from the substance is rotated from the original. A substance capable of causing this rotation is optically active . The degree to which the light is rotated by the enantiomer is determined by finding the angle another polarizer must be turned to in order to produce a dark field.