In short
An ionic bond forms by the complete transfer of electrons from a metal to a non-metal (creating ions); a covalent bond forms by the sharing of electron pairs between non-metals.
Ionic Bond vs Covalent Bond — Comparison Table
| Basis | Ionic Bond | Covalent Bond |
|---|---|---|
| Formation | Transfer of electrons | Sharing of electrons |
| Formed between | Metal + non-metal | Non-metal + non-metal |
| Particles | Ions (cation + anion) | Molecules |
| Melting/boiling point | High | Generally low |
| Conductivity | Conducts when molten/aqueous | Usually non-conducting |
| Examples | NaCl, MgO | H₂O, CO₂, CH₄ |
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