9701/23/O/N/25 · Chemistry October/November 2025 Paper 23
4 questions, 60 marks. Each one links to its official mark scheme.
- Question 1 · 20 marks · Particles in the atom and atomic radius, Isotopes, Relative masses of atoms and molecules, Mass spectrometry, Electrons, energy levels and atomic orbitals, Oxidation and reduction, Oxidation numbers, Balancing redox equations, Intermolecular forces, Dynamic equilibrium, Le Chatelier's principle, Period 3 chlorides with water
- Question 2 · 11 marks · Particles in the atom and atomic radius, Oxidation numbers of oxides and chlorides, Period 3 oxides and hydroxides, Thermal decomposition
- Question 3 · 13 marks · Formulas, Structural isomerism, Characteristic organic reactions, Alkanes, Electrophilic addition, Hess’s law, Oxidising alkenes, Infrared spectroscopy
- Question 4 · 16 marks · Characteristic organic reactions, Making halogenoalkanes, Elimination, Making alkenes, Addition polymerisation, Cis/trans isomerism, Optical isomerism, Organic formulas and naming, Mass spectrometry
Questions and mark schemes from Cambridge International past papers. Paperstreak isn't affiliated with Cambridge.