Chemical Bonding
Chemical bonds are the forces that hold atoms together in molecules, including covalent, ionic, and metallic bonds.
Chemical Bonding
Atoms bond to achieve a more stable electron configuration — typically a full valence shell (the octet rule).
Covalent Bonds
Atoms share electrons. Covalent bonds are classified by the number of shared electron pairs:
- Single bond — 1 pair (e.g., H–H, C–H)
- Double bond — 2 pairs (e.g., C=O, C=C)
- Triple bond — 3 pairs (e.g., N≡N, C≡C)
Bond strength increases with bond order: single < double < triple.
Ionic Bonds
One atom donates electrons to another. The resulting ions are held together by electrostatic attraction:
Na (loses e⁻) → Na⁺ + Cl (gains e⁻) → Cl⁻ → NaCl lattice
Ionic compounds typically have high melting points and conduct electricity when dissolved.
Metallic Bonds
Electrons are delocalised across a lattice of metal cations, giving metals their conductivity and malleability.
The Octet Rule
Atoms tend to gain, lose, or share electrons to achieve eight valence electrons (like noble gases). Exceptions include hydrogen (2 electrons) and elements in period 3+ that can expand their octet.
Related molecules: Water, Sodium Chloride, Oxygen
Try the tool: Lewis Structure Visualizer