Optically active

Definition

Optically active substances rotate the plane of polarized light passing through them. This property is due to asymmetry in their molecular structure.

5 Must Know Facts For Your Next Test

1. Optical activity is measured using a polarimeter.
2. The angle by which the plane of light is rotated is known as the optical rotation.
3. Chiral molecules are typically optically active.
4. Enantiomers are mirror-image forms of a molecule that exhibit opposite optical activities.
5. Optical activity can be observed in both organic and inorganic compounds.

Review Questions

• What instrument is used to measure optical activity?
• How does a chiral molecule affect polarized light?
• What term describes the angle by which polarized light is rotated?

Related terms

Polarized Light: Light waves in which the vibrations occur in a single plane.

Chirality: A property of asymmetry where an object or molecule cannot be superimposed on its mirror image.

Enantiomers: Two stereoisomers that are mirror images of each other and not superimposable.