Double bond

Definition

A double bond is a type of covalent bond in which two pairs of electrons are shared between two atoms. Double bonds are commonly found in organic molecules and influence molecular geometry and reactivity.

5 Must Know Facts For Your Next Test

1. Double bonds consist of one sigma ($\sigma$) bond and one pi ($\pi$) bond.
2. They result in sp2 hybridization in the bonded atoms, leading to a planar structure with 120-degree bond angles.
3. Double bonds restrict the rotation around the bonded atoms, creating rigidity in the molecule.
4. The presence of a double bond typically shortens the bond length compared to a single bond but makes it stronger.
5. Compounds with double bonds often participate in characteristic reactions such as addition reactions.

Review Questions

• What types of bonds make up a double bond?
• How does the presence of a double bond affect the geometry of a molecule?
• Why do double bonds restrict rotation around the bonded atoms?

Related terms

Sigma Bond:

A sigma ($\sigma$) bond is a type of covalent bond formed by the head-on overlap of atomic orbitals, allowing free rotation around the bond axis.

Pi Bond: A pi ($\pi$) bond is formed by the side-by-side overlap of p-orbitals, restricting rotational freedom and occurring alongside a sigma ($\sigma$) bond in double and triple bonds.

Hybridization:

Hybridization involves mixing atomic orbitals to form new hybrid orbitals suitable for pairing electrons to form chemical bonds, influencing molecular shape.