5070/42/O/N/25 · O Level Chemistry October/November 2025 Paper 42
4 questions, 40 marks. Each one links to its official mark scheme.
- Question 1 · 6 marks · Experimental design, Rate of reaction
- Question 2 · 14 marks · Exothermic and endothermic reactions, The mole and the Avogadro constant, Experimental design
- Question 3 · 14 marks · Identification of ions and gases, The characteristic properties of acids and bases
- Question 4 · 6 marks · Exothermic and endothermic reactions
Questions and mark schemes from Cambridge International past papers. Paperstreak isn't affiliated with Cambridge.