| Chemistry | 1. Properties and Structure of Atoms • Use atomic structure, isotopes, electron configuration, the periodic table, periodic trends, empirical and molecular formulas, formula units, Lewis structures, valence electrons, and bonding/lone-pair reasoning at QCE Unit 1 level.• For harder questions, include periodic trend interpretation, Lewis structures, formula interpretation, data tables, model comparison, and evidence-based reasoning about atomic structure.2. Properties and Structure of Materials • Use elements, compounds, mixtures, homogeneous and heterogeneous mixtures, ionic/covalent/metallic bonding, intermolecular forces, structure-property relationships, physical properties of pure substances and mixtures, and materials classification.• For harder questions, include structure-property explanation, bonding diagrams, physical-property data, mixture analysis, and model limitations.3. Chemical Reactions - Reactants, Products and Energy Change • Use chemical reactions, phase changes, balanced equations including state symbols, energy changes, exothermic/endothermic reactions, mole concept, conservation of mass, molar mass, limiting reagent, percentage yield, empirical formula from mass change, enthalpy change, calorimetry, and Hess's law at syllabus level.• For harder questions, include multi-step stoichiometry, limiting reagent reasoning, percentage yield, calorimetry data, energy-profile interpretation, and experimental data analysis.4. Data Test and Working Scientifically • Use QCE Chemistry data-test and working-scientifically skills: analysing experimental data, uncertainty, graphing, identifying trends, evaluating methods, interpreting evidence, and drawing justified conclusions.• For harder questions, include unfamiliar data sets, uncertainty or error analysis, graph interpretation, method evaluation, limitations, and evidence-based conclusions. | 1. Intermolecular Forces and Gases • Use intermolecular forces, molecular substances, boiling/melting point trends, polarity, hydrogen bonding, dispersion forces, dipole-dipole interactions, gas behaviour, gas laws, and physical-property reasoning.• For harder questions, include intermolecular force comparison, property-data interpretation, gas-law calculations, graph interpretation, and model assumptions.2. Aqueous Solutions and Acidity • Use solubility, ionic and molecular substances in water, aqueous reactions, precipitation reactions, acid-carbonate reactions, acidity, pH, acid/base behaviour at Unit 2 level, molarity, concentration, dilution, and ion testing.• For harder questions, include solution concentration calculations, precipitation/ion-identification data, pH interpretation, solubility reasoning, and experimental observations.3. Rates of Chemical Reactions • Use reaction rates, collision theory, activation energy at school level, effects of concentration, temperature, surface area, pressure for gases where appropriate, catalysts, reaction-rate graphs, and experimental measurement of rates.• For harder questions, include rate graphs, interpreting experimental rate data, comparing reaction conditions, identifying rate-limiting factors, and evaluating methods.4. Student Experiment and Working Scientifically • Use QCE Chemistry student-experiment skills: research question, hypothesis, variables, risk, method design, data collection, uncertainty, graphing, analysis, conclusion, validity, reliability, and improvements.• For harder questions, include experimental scenarios, judging method validity, interpreting uncertainty, identifying limitations, improving investigations, and evidence-based conclusions. | 1. Chemical Equilibrium Systems • Use reversible reactions, dynamic equilibrium, equilibrium position, Le Chatelier's principle, equilibrium constants, reaction quotient where appropriate to syllabus level, equilibrium calculations, and industrial or environmental equilibrium contexts.• For harder questions, include equilibrium tables, graphs, stress-response reasoning, K expression interpretation, multi-step equilibrium reasoning, and evaluating assumptions.2. Acid-Base Equilibria • Use acid-base theories, strong and weak acids and bases, ionisation, pH, pOH, Ka/pKa where appropriate, buffers, neutralisation, titration curves, indicators, and volumetric analysis.• For harder questions, include titration data, pH calculations, buffer reasoning, acid-base equilibrium interpretation, indicator selection, multi-step volumetric calculations, and method evaluation.3. Oxidation and Reduction • Use oxidation numbers, oxidation and reduction, redox equations, electrochemical cells, galvanic cells, electrolytic cells, cell potentials where appropriate, electron transfer, and applications of redox chemistry.• For harder questions, include cell diagrams, half-equation balancing, interpreting electrochemical data, redox titration reasoning, and evaluating redox applications.4. Student Experiment and Working Scientifically • Use QCE Chemistry Unit 3 student-experiment skills: developing research questions, modifying experiments, controlling variables, analysing data, uncertainty, validity, reliability, limitations, and evidence-based conclusions.• For harder questions, include IA2-style experiment scenarios, titration/equilibrium/redox data, uncertainty bars, graph analysis, method critique, data interpretation, and improvements. | 1. Properties and Structure of Organic Materials • Use organic structures, functional groups, homologous series, IUPAC naming, structural formulas, isomerism, volatility, solubility, intermolecular forces in organic compounds, and structure-property relationships.• For harder questions, include structural formula interpretation, isomer comparison, functional group identification, property trend data, and explanation of structure-property relationships.2. Chemical Synthesis and Design • Use organic reaction types, reaction pathways, synthesis design, polymers, functional group transformations, reagents and conditions at syllabus level, yield, atom economy or sustainability where appropriate, and design of useful organic materials.• For harder questions, include reaction pathway completion, reagent/product identification, synthesis planning, polymer reasoning, yield or atom economy calculations, and sustainability evaluation.3. Analytical Techniques and Chemical Analysis • Use qualitative and quantitative chemical analysis, chromatography, spectroscopy, mass spectrometry, infrared spectroscopy, NMR where appropriate to syllabus scope, structural analysis, and applying chemical data to identify or evaluate substances.• For harder questions, include chromatogram interpretation, spectra interpretation, structural deduction from multiple data sources, concentration analysis, and method selection.4. Research Investigation and Working Scientifically • Use QCE Chemistry research-investigation skills: analysing secondary sources, evaluating evidence, identifying claims, comparing models, judging credibility, synthesising information, and communicating a justified conclusion.• For harder questions, include research-style prompts, secondary data, competing claims, source limitations, model evaluation, and evidence-based reasoning. |
