Wales Β· WJECSyllabus
Chemistry syllabus, dot point by dot point
Every dot point in the Wales Chemistrysyllabus, with a focused answer for each one. Click any dot point for a worked explainer, past exam questions, and links to related dot points. Written by Claude Opus 4.8, Anthropic's latest AI.
Unit 1: The Language of Chemistry, Structure and Physical Chemistry
Module overview β- What are atoms made of and how are their electrons arranged?Sub-atomic particles, isotopes, mass spectrometry and relative atomic mass, electron configurations in s, p and d sub-shells, and successive ionisation energies.12 min answer β
- How are atoms held together and what shapes do molecules take?Ionic, covalent, dative and metallic bonding, electronegativity and polarity, intermolecular forces, and the shapes of simple molecules from electron-pair repulsion.12 min answer β
- How do we count atoms and quantify what happens in a reaction?The mole, Avogadro constant, molar mass, concentration, the ideal gas equation, empirical and molecular formulae, and percentage yield and atom economy.12 min answer β
- How do we write what happens in a chemical reaction?Oxidation numbers, formulae of ionic and covalent compounds, writing and balancing full, ionic and half equations, and state symbols.11 min answer β
- What is dynamic equilibrium and how do acids and bases behave?Dynamic equilibrium, Le Chatelier's principle, the Bronsted-Lowry model of acids and bases, strong and weak acids, and acid-base titrations.11 min answer β
- How does the structure of a solid explain its properties?Giant ionic, giant covalent, simple molecular and metallic structures, and how bonding and structure explain melting point, conductivity, hardness and solubility.11 min answer β
- How do properties of elements vary across the periodic table?Periodicity of atomic radius, ionisation energy, melting point and electronegativity across Period 3, and trends in Group 2 and Group 7 chemistry.11 min answer β
Unit 2: Energy, Rate and Chemistry of Carbon Compounds
Module overview β- How are alcohols and carboxylic acids made and how do they react?Classification and oxidation of alcohols, dehydration and esterification, the reactions of carboxylic acids, and the preparation and hydrolysis of esters.12 min answer β
- How do halogenoalkanes react and how does their structure affect rate?Nucleophilic substitution and elimination of halogenoalkanes, the effect of carbon-halogen bond strength on rate, and the environmental impact of CFCs on the ozone layer.11 min answer β
- How do alkanes and alkenes react and why?Alkanes and alkenes, free-radical substitution, electrophilic addition, Markovnikov addition, addition polymerisation, and combustion.12 min answer β
- How do we name and represent organic molecules?Functional groups, homologous series, IUPAC nomenclature, structural and displayed formulae, structural and E/Z isomerism, and reaction mechanism notation.11 min answer β
- What controls how fast a reaction goes?Collision theory, activation energy, the effect of concentration, temperature, surface area and catalysts on rate, and the Maxwell-Boltzmann distribution.11 min answer β
- How does chemistry affect society, the economy and the environment?Green chemistry, atom economy and percentage yield, sustainable feedstocks and energy, the carbon footprint of processes, and the social and economic impact of chemical manufacture.11 min answer β
- Where does the energy of a reaction come from and how is it measured?Enthalpy changes, exothermic and endothermic reactions, calorimetry, standard enthalpies of formation and combustion, Hess's law and bond enthalpies.12 min answer β
Unit 3: Physical and Inorganic Chemistry
Module overview β- How do we measure acidity and control pH?pH, Ka and pKa, strong and weak acids and bases, the ionic product of water, buffer solutions and pH titration curves.12 min answer β
- How do we express rate mathematically and deduce a mechanism?Rate equations, orders of reaction, the rate constant, half-life, determining orders from data, the rate-determining step and the Arrhenius equation.12 min answer β
- What makes the transition metals special?Transition metal characteristics, variable oxidation states, complex ions and ligands, coloured ions, catalysis, and ligand substitution.12 min answer β
- How do properties vary across and down the p-block?Trends in Group 3 to Group 7, the inert pair effect, oxides and chlorides of Period 3, oxidising and reducing behaviour, and tests for ions.12 min answer β
- What makes a reaction feasible?Born-Haber cycles and lattice enthalpy, enthalpy of solution, entropy, and Gibbs free energy as the criterion for feasibility.12 min answer β
- How do we quantify the position of an equilibrium?The equilibrium constants Kc and Kp, writing and evaluating expressions, units, the effect of changing conditions, and the role of a catalyst.12 min answer β
- How do electrode potentials predict redox behaviour?Standard electrode potentials, the standard hydrogen electrode, electrochemical cells, calculating cell EMF, and predicting the feasibility of redox reactions.12 min answer β
- How do we track and balance electron transfer?Oxidation and reduction in terms of electron transfer and oxidation number, oxidising and reducing agents, redox half equations, and redox titrations.12 min answer β
Unit 4: Organic Chemistry and Analysis
Module overview β- How do alcohols and phenols differ in their reactions?The reactions of alcohols, oxidation and dehydration, the acidity and characteristic reactions of phenols, and tests to distinguish them.12 min answer β
- How do carbonyl compounds react and how do we tell them apart?The carbonyl group, nucleophilic addition, reduction and oxidation of aldehydes and ketones, and tests to identify and distinguish them.12 min answer β
- How do nitrogen-containing organic molecules behave?The preparation and basicity of amines, the properties of amino acids and zwitterions, peptide bonds, and the formation of polyamides and proteins.12 min answer β
- Why is benzene so stable and how does it react?The structure and stability of benzene, the delocalised model, electrophilic substitution reactions, and the reactions of phenol.12 min answer β
- How do carboxylic acids and their derivatives react?Carboxylic acids and their acidity, esters, acyl chlorides and acid anhydrides, and the reactions and interconversions of these derivatives.12 min answer β
- How do we plan a multi-step synthesis and check the product?Reaction pathways linking functional groups, planning multi-step syntheses, practical techniques of preparation and purification, and assessing purity.12 min answer β
- How do we determine the structure of an unknown molecule?Mass spectrometry, infrared spectroscopy, proton and carbon-13 NMR, and chromatographic separation in structure determination.12 min answer β
- How can molecules with the same formula differ in three dimensions?E/Z isomerism, optical isomerism and chirality, the rotation of plane-polarised light, racemic mixtures, and the importance of stereochemistry in drugs.11 min answer β