Chirality (chemistry)

Chirality (pronounced: kai-ral-ity) is a property of asymmetry important in several branches of science, including chemistry, biology, and physics. The term chirality is derived from the Greek word for hand, "cheir". The concept of chirality in chemistry was first introduced by Louis Pasteur.

Definition

In chemistry, chirality usually refers to molecules. A chiral molecule is a type of molecule that has a non-superposable mirror image. The feature that is most often the cause of chirality in molecules is the presence of an asymmetric carbon atom.

Chiral Molecules

Chiral molecules are defined as molecules that cannot be superimposed on their mirror images. In other words, the molecule and its mirror image are different in some way. This difference is often due to the presence of an asymmetric carbon atom, which is a carbon atom that is attached to four different types of atoms or groups of atoms.

Asymmetric Carbon Atom

An asymmetric carbon atom (also known as a chiral center) is a carbon atom that is attached to four different types of atoms or groups of atoms. This is the most common cause of chirality in molecules. When a molecule has more than one asymmetric carbon atom, it can have multiple chiral centers.

Optical Activity

Chiral molecules exhibit a property known as optical activity. Optical activity is the ability of a chiral molecule to rotate the plane of polarization of light. This property is used to distinguish between the two forms of a chiral molecule, known as enantiomers.

Enantiomers

Enantiomers are pairs of molecules that are mirror images of each other but are not superimposable. They are a type of stereoisomer. Enantiomers have the same physical and chemical properties, but they differ in the direction in which they rotate the plane of polarization of light. One enantiomer will rotate light in a clockwise direction (dextrorotatory), and the other will rotate light in a counterclockwise direction (levorotatory).

Related Terms

• Stereochemistry
• Stereoisomer
• Optical Isomer
• Racemic Mixture
• Enantiomeric Excess

External links

• Medical encyclopedia article on Chirality (chemistry)
• Wikipedia's article - Chirality (chemistry)

This WikiMD dictionary article is a stub. You can help make it a full article.

---

Languages: - East Asian 中文, 日本, 한국어, South Asian हिन्दी, Urdu, বাংলা, తెలుగు, தமிழ், ಕನ್ನಡ,
Southeast Asian Indonesian, Vietnamese, Thai, မြန်မာဘာသာ, European español, Deutsch, français, русский, português do Brasil, Italian, polski