Specification points
WJEC A-level Chemistry A410QS
266 points in 12 topics, with WJEC's codes and titles.
Grade boundaries·WJEC command words
Codes and titles are read by a script from WJEC's published specification and have not been checked by a person. What each point covers is in the specification itself: WJEC’s specification.
C1 Topic C1: The language of chemistry and structure of matter
- C1.1 Formulae and equations
- C1.1(a) Formulae of compounds and ions
- C1.1(b) Oxidation numbers of atoms in a compound or ion
- C1.1(c) Balanced chemical and ionic equations
- C1.2 Basic ideas about atoms
- C1.2(a) Radioactive decay
- C1.2(b) Properties of alpha, beta and gamma radiation
- C1.2(c) Half-life of radioactive decay
- C1.2(d) Effects and uses of radioisotopes
- C1.2(e) Ionisation energies
- C1.2(f) Link between successive ionisation energy values and electronic structure
- C1.2(g) Atomic orbitals and electron configuration
- C1.2(h) Emission and absorption spectra
- C1.2(i) Atomic emission spectrum of the hydrogen atom
- C1.2(j) Energy, frequency and wavelength
- C1.2(k) Order of increasing energy of infrared, visible and ultraviolet light
- C1.2(l) Lyman series convergence limit and ionisation energy
- C1.3 Chemical calculations
- C1.3(a) Relative mass terms (atomic, isotopic, formula, molecular)
- C1.3(b) The mass spectrometer
- C1.3(c) Simple mass spectra, for example, that of chlorine gas
- C1.3(d) Empirical and molecular formulae
- C1.3(e) Relationship between the Avogadro constant, the mole and molar mass
- C1.3(f) Relationship between grams and moles
- C1.3(g) Concentration and solubility
- C1.3(h) Molar volume of gases
- C1.3(i) Ideal gas equation (pV = nRT)
- C1.3(j) Stoichiometry and titrations
- C1.3(k) Concepts of atom economy and percentage yield
- C1.3(l) Percentage error and significant figures
- C1.4 Bonding
- C1.4(a) Ionic bonding
- C1.4(b) Covalent and coordinate bonding
- C1.4(c) Intermediate character of many bonds between purely ionic and purely covalent
- C1.4(d) Concepts of electronegativity and bond polarity
- C1.4(e) Forces between molecules being much weaker than covalent (and ionic) bonds
- C1.4(f) Permanent and temporary dipoles
- C1.4(g) Hydrogen bonding
- C1.4(h) VSEPR and shapes of molecules and ions
- C1.4(i) Bond angles in molecules and ions
- C1.5 Solid structures
- C1.5(a) Crystal structures of sodium chloride and caesium chloride
- C1.5(b) Structures of diamond and graphite
- C1.5(c) Structures of iodine and ice
- C1.5(d) ‘electron sea’ model for bonding in metals
- C1.5(e) Physical properties, structure and bonding
- C1.6 The Periodic Table
- C1.6(a) Elements being arranged according to atomic number in the Periodic Table
- C1.6(b) Electronic structure and the Periodic Table blocks
- C1.6(c) Oxidation and reduction as electron transfer
- C1.6(d) Trends in ionisation energy, melting temperature and electronegativity
- C1.6(e) Reactions of Group 2 elements with oxygen and water/steam
- C1.6(f) Reactions of Group 2 aqueous cations
- C1.6(g) Flame colours of s-block compounds
- C1.6(h) Trend in general reactivity of Group 1 and Group 2 metals
- C1.6(i) Trend in thermal stability of the Group 2 carbonates and hydroxides
- C1.6(j) Trends in solubility of Group 2 hydroxides and sulfates
- C1.6(k) Basic character of Group 1 and 2 oxides and hydroxides
- C1.6(l) Trend in volatility of Group 7 elements (halogens)
- C1.6(m) Reactions of the halogens with metals
- C1.6(n) Trend in reactivity of the halogens in terms of relative oxidising power
- C1.6(o) Reaction between aqueous Ag⁺ and halide ions followed by dilute aqueous NH3
- C1.6(p) Displacement reactions of halogens in terms of redox
- C1.6(q) Chlorine and fluoride in water treatment
- C1.6(r) Salt formation, precipitation and gravimetric analysis
C2 Topic C2: Chemical change
- C2.1 Simple equilibria and acid-base reactions
- C2.1(a) Reversible reactions and dynamic equilibrium
- C2.1(b) Le Chatelier's principle
- C2.1(c) Equilibrium constant Kc and calculations from equilibrium concentrations
- C2.1(d) Acids and bases as proton donors and acceptors
- C2.1(e) pH and hydrogen ion concentration
- C2.1(f) Acid-base titrations
- C2.1(g) Difference between strong acids and weak acids in terms of relative dissociation
- C2.2 Thermochemistry
- C2.2(a) Enthalpy changes of reaction, combustion and formation
- C2.2(b) Hess’s law and energy cycles
- C2.2(c) Average bond enthalpies
- C2.2(d) Calculating enthalpy changes
- C2.2(e) Determining enthalpy changes experimentally
- C2.3 Rates of reaction
- C2.3(a) Collision theory in explaining the effects of changing conditions on reaction rate
- C2.3(b) Calculating rates and rate–concentration relationships
- C2.3(c) Concepts of energy profiles and activation energy
- C2.3(d) Temperature and the Boltzmann distribution
- C2.3(e) Characteristics of a catalyst
- C2.3(f) Catalysts and activation energy
- C2.3(g) Colorimetry in rate studies
- C2.3(h) Measuring reaction rates
- C2.4 The wider impact of chemistry
- C2.4(a) Impact of chemical synthesis and energy production
- C2.4(b) Role of green chemistry in improving sustainability in all aspects of developments
C3 Topic C3: Chemistry of carbon compounds
- C3.1 Organic compounds
- C3.1(a) Formulae of organic compounds
- C3.1(b) Nomenclature rules relating to alkanes, alkenes, halogenoalkanes, alcohols and carboxylic acids
- C3.1(c) Chain length, functional groups and physical properties
- C3.1(d) Concept of structural isomerism
- C3.1(e) Electrophiles, nucleophiles, radicals and bond fission
- C3.2 Hydrocarbons
- C3.2(a) Combustion of alkanes and fossil fuels
- C3.2(b) C—C and C—H bonds in alkanes as σ-bonds
- C3.2(c) Mechanism of radical substitution, such as the photochlorination of alkanes
- C3.2(d) Reactivity of alkanes and alkenes
- C3.2(e) C=C bond in ethene and other alkenes as comprising π-bond and σ-bond
- C3.2(f) E–Z isomerism in terms of restricted rotation about a carbon-carbon double bond
- C3.2(g) Electrophilic addition to alkenes
- C3.2(h) Bromine/bromine water and potassium manganate(VII) tests for alkenes
- C3.2(i) Addition of HBr to propene and carbocation stability
- C3.2(j) Catalytic hydrogenation of ethene
- C3.2(k) Addition polymerisation
- C3.3 Halogenoalkanes
- C3.3(a) Elimination reactions of halogenoalkanes
- C3.3(b) Nucleophilic substitution of halogenoalkanes
- C3.3(c) Bond polarity, bond enthalpy and substitution
- C3.3(d) Hydrolysis/Ag⁺(aq) test for halogenoalkanes
- C3.3(e) Uses and regulation of halogenoalkanes
- C3.3(f) Environmental effects of CFCs
- C3.3(g) Heating under reflux
- C3.4 Alcohols and carboxylic acids
- C3.4(a) Industrial preparation of ethanol from ethene
- C3.4(b) Preparing alcohols by fermentation; biofuels
- C3.4(c) Dehydration reactions of alcohols
- C3.4(d) Classification of alcohols as primary, secondary and tertiary
- C3.4(e) Oxidation of primary alcohols to aldehydes/carboxylic acids and secondary alcohols to ketones
- C3.4(f) Dichromate(VI) test for primary/secondary alcohols and sodium hydrogencarbonate test for carboxylic acids
- C3.4(g) Reactions of carboxylic acids with bases, carbonates and hydrogencarbonates forming salts
- C3.4(h) Esterification
- C3.4(i) Separation by distillation
- C3.5 Instrumental analysis
- C3.5(a) Mass spectra and chemical structure
- C3.5(b) Infrared spectra and chemical structure
- C3.5(c) NMR spectra and chemical structure
PI1 Topic PI1: Electrochemistry
- PI1.1 Redox and standard electrode potential
- PI1.1(a) Redox reactions in terms of electron transfer
- PI1.1(b) Half-equations, half-cells and cell diagrams
- PI1.1(c) Concept of standard electrode potential and role of the standard hydrogen electrode
- PI1.1(d) Electrochemical cells
- PI1.1(e) Cell EMF and feasibility of reactions
- PI1.1(f) Principles of the hydrogen fuel cell and its benefits and drawbacks
- PI1.2 Redox reactions
- PI1.2(a) Constructing ion/electron half-equations
- PI1.2(b) Combining half-equations
- PI1.2(c) Copper(II) and iodide redox; iodine determined with thiosulfate
- PI1.2(d) Redox titrations
PI2 Topic PI2: More complex patterns of the Periodic Table
- PI2.1 Chemistry of the p-block
- PI2.1(a) Amphoteric behaviour of p-block elements
- PI2.1(b) The inert pair effect
- PI2.1(c) Incomplete and expanded octets
- PI2.1(d) Aluminium chloride and donor-acceptor compounds
- PI2.1(e) Hexagonal and cubic boron nitride
- PI2.1(f) Oxidation states II and IV in Group 4
- PI2.1(g) Carbon dioxide and lead(II) oxide
- PI2.1(h) Bonding in Group 4 chlorides
- PI2.1(i) Reactions of lead(II) ions
- PI2.1(j) Chlorine with aqueous sodium hydroxide; disproportionation
- PI2.1(k) Bleaching and bactericidal action of chlorine
- PI2.1(l) Sodium halides with concentrated sulfuric acid
- PI2.2 Chemistry of the d-block transition metals
- PI2.2(a) How the d-block elements attain various oxidation states in their compounds
- PI2.2(b) Oxidation states and colours of transition metal ions
- PI2.2(c) Bonding in tetrahedral and octahedral complexes
- PI2.2(d) Origin of colour in transition metal complexes
- PI2.2(e) Ligand exchange and coordination number
- PI2.2(f) Colours and formulae of complex ions
- PI2.2(g) Transition metals as catalysts
- PI2.2(h) Nickel and iron as industrial catalysts
- PI2.2(i) Vanadium(V) oxide and manganese(IV) oxide as catalysts
- PI2.2(j) Reactions of Cr³⁺, Fe²⁺, Fe³⁺ and Cu²⁺ with excess aqueous OH⁻
PI3 Topic PI3: Chemical kinetics
PI4 Topic PI4: Energy changes
- PI4.1 Enthalpy changes for solids and solutions
- PI4.1(a) Enthalpy changes of atomisation, lattice, hydration and solution
- PI4.1(b) Solubility and enthalpy change of solution
- PI4.1(c) Born-Haber cycles
- PI4.1(d) Enthalpy of formation and stability
- PI4.2 Entropy and feasibility of reactions
- PI4.2(a) Entropy
- PI4.2(b) Entropy of solids, liquids and gases
- PI4.2(c) Calculating entropy changes
- PI4.2(d) Gibbs free energy
- PI4.2(e) Spontaneous reactions and free energy
PI5 Topic PI5: Equilibria
- PI5.1 Equilibrium constants
- PI5.1(a) Temperature and equilibrium constants
- PI5.1(b) Calculating Kp, Kc and equilibrium quantities
- PI5.1(c) Magnitude of the equilibrium constant
- PI5.2 Acid-base equilibria
- PI5.2(a) Lowry-Bronsted theory of acids and bases
- PI5.2(b) Strong and weak acids and bases; Ka
- PI5.2(c) Significance of the ionic product of water, Kw
- PI5.2(d) Calculations with pH, Ka, pKa and Kw
- PI5.2(e) Titration curves
- PI5.2(f) Buffer solutions
- PI5.2(g) Importance of buffer solutions in living systems and industrial processes
- PI5.2(h) Hydrolysis of salts
- PI5.2(i) Choosing indicators for titrations
OA1 Topic OA1: Higher concepts in organic chemistry
- OA1.1 Stereoisomerism
- OA1.1(a) Stereoisomerism: E–Z and optical isomerism
- OA1.1(b) The terms chiral centre, enantiomer, optical activity and racemic mixture
- OA1.1(c) Optical isomerism in terms of an asymmetric carbon atom
- OA1.1(d) Effect of an enantiomer on plane-polarised light
- OA1.2 Aromaticity
- OA1.2(a) Structure of and bonding in benzene and other arenes
- OA1.2(b) Resistance to addition reactions shown by aromatic compounds such as benzene
- OA1.2(c) Electrophilic substitution in benzene
- OA1.2(d) Interaction between benzene and substituents
OA2 Topic OA2: Organic compounds containing oxygen
- OA2.1 Alcohols and phenols
- OA2.1(a) Methods of forming primary and secondary alcohols from halogenoalkanes and carbonyl compounds
- OA2.1(b) Reactions of primary and secondary alcohols
- OA2.1(c) Acidity of phenol and its reactions with bromine and ethanoyl chloride
- OA2.1(d) Iron(III) chloride test for phenols
- OA2.2 Aldehydes and ketones
- OA2.2(a) Oxidation of alcohols to aldehydes and ketones
- OA2.2(b) Distinguishing aldehydes and ketones
- OA2.2(c) Reduction of aldehydes and ketones using NaBH4
- OA2.2(d) Nucleophilic addition to carbonyl compounds
- OA2.2(e) 2,4-DNPH test for carbonyl groups
- OA2.2(f) Triiodomethane (iodoform) test
- OA2.3 Carboxylic acids and their derivatives
- OA2.3(a) Relative acidity of acids, phenols, alcohols and water
- OA2.3(b) Formation of carboxylic acids by the oxidation of alcohols and aldehydes
- OA2.3(c) Reduction of carboxylic acids using LiAlH4
- OA2.3(d) Formation of aromatic carboxylic acids by the oxidation of methyl side-chains
- OA2.3(e) Decarboxylation of carboxylic acids
- OA2.3(f) Esters and acid chlorides from carboxylic acids
- OA2.3(g) Conversion of carboxylic acids to amides and nitriles
- OA2.3(h) Formation of nitriles from halogenoalkanes and hydroxynitriles from aldehydes and ketones
- OA2.3(i) Hydrolysis of nitriles and amides
- OA2.3(j) Reduction of nitriles using LiAlH4
OA3 Topic OA3: Organic compounds containing nitrogen
- OA3.1 Amines
- OA3.1(a) Formation of primary aliphatic amines from halogenoalkanes and nitriles
- OA3.1(b) Formation of aromatic amines from nitrobenzenes
- OA3.1(c) Basicity of amines
- OA3.1(d) Ethanoylation of primary amines using ethanoyl chloride
- OA3.1(e) Reaction of primary amines (aliphatic and aromatic) with cold nitric(III) acid
- OA3.1(f) Coupling of benzenediazonium salts with phenols and aromatic amines
- OA3.1(g) Role of the —N=N— chromophore in azo dyes
- OA3.1(h) Origin of colour in terms of the wavelengths of visible light absorbed
- OA3.2 Amino acids, peptides and proteins
- OA3.2(a) General formula and classification of α-amino acids
- OA3.2(b) Amino acids as amphoteric zwitterions
- OA3.2(c) Combination of α-amino acids to form dipeptides
- OA3.2(d) Formation of polypeptides and proteins
- OA3.2(e) Basic principles of primary, secondary and tertiary protein structure
- OA3.2(f) Essential role of proteins in living systems, for example, as enzymes
OA4 Topic OA4: Organic synthesis and analysis
- OA4(a) Synthesis of organic compounds by a sequence of reactions
- OA4(b) Techniques of manipulation, separation and purification
- OA4(c) Distinction between condensation polymerisation and addition polymerisation
- OA4(d) Polyesters and polyamides
- OA4(e) Melting temperature and purity
- OA4(f) High resolution 1H NMR spectra and structure elucidation
- OA4(g) Chromatography: TLC, paper, GC and HPLC