Simple molecular substance: A substance consisting of small molecules held together internally by strong covalent bonds, with weak intermolecular forces between different molecules.
Intermolecular forces: Weak forces of attraction between separate molecules (distinct from intramolecular covalent bonds which are within molecules).
Intramolecular bond: A bond within a molecule — the strong covalent bonds between atoms making up a molecule.
Boiling point: The temperature at which a liquid becomes a gas — determined by how much energy is needed to overcome intermolecular forces, not intramolecular bonds.
This definitions covers Key Definitions within Simple Molecules for GCSE Chemistry. Revise Simple Molecules in Bonding & Structure for GCSE Chemistry with 20 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 5 of 11 in this topic. Make sure you can use the exact wording confidently, because definition marks are often lost through vague language.
Practice questions for Simple Molecules
Which type of force holds simple molecules together as a substance?
Explain why chlorine (Cl2) has a low boiling point.