A double covalent bond is a type of chemical bond in which two pairs of electrons (four electrons total) are shared between two atoms.
- In a single covalent bond, only one pair of electrons is shared.
- In a double bond, two pairs are shared, making the bond stronger and shorter than a single bond, but weaker and longer than a triple bond.
For example:
- In an oxygen molecule (O₂), each oxygen atom has six valence electrons. To complete their octet, they each share two pairs of electrons, forming a double bond (O=O).
- In carbon dioxide (CO₂), carbon forms two double bonds with two oxygen atoms (O=C=O).
Key points about double covalent bonds:
- Involve 4 shared electrons.
- Stronger than single bonds but weaker than triple bonds.
- Found in molecules with unsaturated structures, like alkenes (C=C).