- Covalent bonding = shared pair of electrons between non-metal atoms
- Occurs between non-metals only (both want electrons)
- Electrons are SHARED — NOT transferred (no ions form)
- Single bond = 1 shared pair (e.g., H-H)
- Double bond = 2 shared pairs (e.g., O=O)
- Triple bond = 3 shared pairs (e.g., N≡N)
- Molecules form — distinct particles with fixed composition
- Strong bonds within molecules, but weak forces BETWEEN molecules
- H needs 1 bond, O needs 2, N needs 3, C needs 4
Quick Check: Why does CO₂ have a double bond between carbon and each oxygen atom?
Carbon has 4 outer electrons and needs 4 more to reach 8. Oxygen has 6 outer electrons and needs 2 more. Each oxygen shares 2 pairs of electrons with carbon, forming two double bonds: O=C=O. Carbon gets 4+4 = 8, each oxygen gets 6+2 = 8.
This key facts covers Key Facts to Memorise within Covalent Bonding for GCSE Chemistry. Revise Covalent Bonding in Bonding & Structure for GCSE Chemistry with 25 exam-style questions and 21 flashcards. This topic appears less often, but it can still be a useful differentiator on mixed-topic papers. It is section 8 of 13 in this topic. Use this key facts to connect the idea to the wider topic before moving on to questions and flashcards.
Practice questions for Covalent Bonding
Which of the following best describes a covalent bond?
Explain the difference between a bonding pair and a lone pair of electrons in a covalent molecule.