2.2.3
Coordination Bonds
Also known as Dative Covalent Bonds.
Definition
Coordinate Bond
A covalent bond in which both electrons of the shared pair originate from the same atom.
Once formed, a coordinate bond is identical to a standard covalent bond in terms of length and strength.
Example 1: Ammonium (NH₄⁺)
NH₃ + H⁺ → NH₄⁺
Nitrogen in Ammonia has a lone pair. The Hydrogen ion (H⁺) has an empty orbital (no electrons). Nitrogen donates both electrons to form the bond.
Example 2: Carbon Monoxide (CO)
:C ≡ O:
To complete the octet for Carbon, Oxygen forms two normal covalent bonds and one coordinate bond (donating a lone pair to Carbon).