9701 · 3.4
Covalent bonding and coordinate (dative covalent) bonding
Atoms form covalent bonds by sharing electrons to achieve a more stable arrangement, like a full outer shell. A coordinate bond is just a special type of covalent bond where one atom generously provides both electrons for the share.
Need to know
What you need to know
- Describe a covalent bond as the strong electrostatic attraction between a shared pair of electrons and the nuclei of bonded atoms.
- Draw 'dot-and-cross' diagrams to represent the valence electrons in simple covalent molecules, including those with multiple bonds.
- Explain and represent coordinate (dative covalent) bonding, where one atom provides both electrons to a shared pair.
- Understand the relationship between the number of shared electron pairs (bond order), bond length, and bond strength.
Explanation
The Ultimate Electron Sharing Agreement
- Covalent bonds form when atoms share electron pairs.
- Each covalent bond = one shared pair (single bond) or multiple pairs (double/triple).
- Dative covalent bonds: both electrons come from one atom (e.g. NH₄⁺).
- Lewis structures show all valence electrons — dots or crosses per atom.