Methane and octane both consist of molecules. Octane molecules are larger than methane molecules, and octane has a higher boiling point than methane. A student says this is because the covalent bonds within an octane molecule are stronger.
Why is the student wrong?
Covalent bonds between octane molecules are stronger than those between methane molecules
The intermolecular forces in octane are stronger because its covalent bonds are stronger
Stronger intermolecular forces act between octane molecules, so more energy is needed to separate them
More covalent bonds are broken when octane boils than when methane boils
84 exam-style questions on AQA GCSE Chemistry 2.2 How bonding and structure are related to the properties of substances, covering 2.2.1a The three states of matter, 2.2.1b Limitations of the simple particle model, 2.2.2 State symbols in chemical equations, 2.2.3 Properties of ionic compounds, 2.2.4 Properties of small molecules, 2.2.5 Polymers, 2.2.6 Giant covalent structures, 2.2.7 Properties of metals and alloys, and 2.2.8 Metals as conductors. Each one has a worked solution and a mark scheme showing where the marks go.