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Foundation Chemistry (Topics 1-10, shared with AS)
Topic 1: Atomic Structure and the Periodic Table
1.1-1.4 - Atoms And Subatomic ParticlesThis lesson covers spec points 1.1-1.4: the structure of an atom in terms of protons, neutrons and electrons; their relative masses and charges; the meanings of atomic number and mass number; and how to determine particle numbers in atoms, molecules and ions. The next lesson uses the same countin...
1.5-1.7 - Isotopes And Relative MassesThis lesson covers Pearson Edexcel 9CH0 spec points 1.5, 1.6 and 1.7: isotopes, relative isotopic mass, relative atomic mass, relative molecular mass and relative formula mass. It deliberately leaves mass-spectrometry abundance calculations, diatomic molecule peak patterns and molecular-ion peaks...
1.8-1.10 - Mass Spectrometry For Relative MassThis lesson covers spec points 1.8, 1.9 and 1.10: using mass-spectrometry data to calculate relative atomic mass from isotope abundance, working backwards from relative atomic mass to isotope abundance, predicting diatomic molecule spectra, and using the molecular ion peak to find relative molecu...
1.11-1.14 - First And Successive Ionisation EnergiesThis lesson covers Edexcel 9CH0 specification points 1.11 to 1.14: defining first and successive ionisation energies, explaining the factors that affect them, and using those factors to explain first ionisation energy trends across a period and down a group. It deliberately leaves the fuller "evi...
1.15 - Evidence For Shells And SubshellsThis lesson covers Pearson Edexcel 9CH0 specification point 1.15: how evidence from atomic emission spectra, successive ionisation energies, and first ionisation energies of successive elements led chemists to the shell and subshell model. It assumes you can already define first and successive io...
1.16-1.22 - Orbitals And Electronic ConfigurationsThis lesson covers Edexcel 9CH0 spec points 1.16-1.22: shell capacities, orbitals, s- and p-orbital shapes, s/p/d subshell capacities, electron-in-box filling, electronic configurations of atoms and selected ions up to Z = 36, and classification into s-, p- and d-block elements. It deliberately s...
1.23-1.26 - Periodicity And Element PropertiesThis lesson covers Edexcel 9CH0 spec points 1.23-1.26: electronic configuration as the driver of chemical properties, periodicity as a repeating pattern across periods, Period 2 and 3 trends in melting and boiling temperatures, Period 2 and 3 first ionisation energy trends, and the use of data su...
Topic 2: Bonding and Structure
2A.1-2A.6 - Ionic Bonding And Ionic EvidenceThis lesson covers Pearson Edexcel 9CH0 2A.1-2A.6: ionic bonding as electrostatic attraction, the effect of ionic charge and radius, ion formation by electron transfer, dot-and-cross diagrams for ions, ionic-radius trends, and evidence for ions from properties and migration. It deliberately leave...
2A.7-2A.9 - Covalent Bonding And Dot Cross DiagramsThis lesson covers Pearson Edexcel 9CH0 spec points 2A.7, 2A.8 and 2A.9: the meaning of a covalent bond, dot-and-cross diagrams for covalent substances including dative covalent bonding, and the relationship between covalent bond length and bond strength. It deliberately stops before 2A.10-2A.12,...
2A.10-2A.12 - Molecular Shapes And Bond AnglesThis lesson covers Pearson Edexcel 9CH0 spec points 2A.10, 2A.11 and 2A.12: how repulsion between electron pairs around a central atom determines the shapes and bond angles of simple molecules and ions, and how to predict related shapes using electron-pair repulsion theory. It uses dot-and-cross...
2A.13-2A.15 - Electronegativity, Bond Polarity And Molecular PolarityThis lesson explains how electronegativity makes covalent bonds polar, why ionic and covalent bonding are better treated as extremes of a continuum, and how to decide whether a whole molecule is polar. It uses the molecular-shape ideas from lesson 010 only as a prerequisite for dipole cancellatio...
2A.16-2A.19 - Intermolecular Forces And Hydrogen BondingThis lesson explains the three intermolecular-force models named by Edexcel: London forces, permanent dipole-dipole forces, and hydrogen bonding. It uses water, liquid ammonia, and liquid hydrogen fluoride to show how hydrogen bonds arise, then applies the model to water's high melting and boilin...
2A.20-2A.21 - Physical Properties And Solvent ChoiceThis lesson applies the intermolecular-force model from the previous lesson to boiling-temperature trends, volatility and solvent choice. It covers alkanes, alcohols, hydrogen halides, water as a solvent for ions and simple alcohols, and non-aqueous solvents for substances with similar intermolec...
2A.22-2B.23 - Metallic Bonding And Giant LatticesThis lesson defines metallic bonding and uses it to place solid metals in the wider family of giant lattices. It deliberately leaves detailed simple molecular structures, carbon allotrope detail, and full property prediction to the following lessons, while giving enough particle-level language to...
2B.24-2B.25 - Simple Molecular And Carbon StructuresThis lesson fixes the language used to describe covalently bonded solids: some contain separate molecules, while others are continuous carbon networks. It covers simple molecular structures such as iodine, I2, and ice, H2O, then compares the different structures formed by carbon atoms in diamond,...
2B.26-2B.27 - Predicting Structure, Bonding And PropertiesThis lesson uses the bonding and structure models from Topic 2 to decide what an unfamiliar substance is like from numerical data and other evidence. It deliberately treats dot-and-cross diagrams, molecular shapes, intermolecular forces, solvent choice, giant lattices and carbon structures as pre...
Topic 3: Redox I
3.1-3.2 - Oxidation NumbersOxidation numbers are a bookkeeping system for tracking electron ownership in compounds and ions. This lesson covers what an oxidation number means and how to calculate it, including the Edexcel-required exceptions for peroxides and metal hydrides. It deliberately stops before classifying reactio...
3.3-3.8 - Oxidation, Reduction And DisproportionationThis lesson turns oxidation numbers from a bookkeeping tool into a way of recognising electron transfer. It covers oxidation and reduction as electron loss/gain and as oxidation-number change, then uses those ideas to identify oxidising agents, reducing agents and disproportionation reactions. It...
3.9-3.13 - Roman Numerals, Formulae And Half EquationsThis lesson turns oxidation numbers into working chemical notation: names with Roman numerals, formulae from ion charges, and half-equations that show electron transfer. It deliberately leaves the detailed chemistry of Group 1, Group 2 and halogen reactions to the next topic, using only short red...
Topic 4: Inorganic Chemistry and the Periodic Table
4A.1-4A.8 - Group 1 And 2 Trends And ReactionsThis lesson builds the Edexcel 9CH0 Topic 4A model for Groups 1 and 2: why Group 2 ionisation energies fall down the group, why the metals become more reactive, how Mg to Ba and their compounds react, and how flame tests and thermal decomposition reveal s-block patterns. It uses electron loss and...
4B.9-4B.11 - Halogen Trends And DisplacementThis lesson explains the Group 7 trends in physical state, melting and boiling temperatures, electronegativity, and reactivity, then uses halogen-halide displacement as redox evidence for the trend. It deliberately stops before chlorine disproportionation, halide tests with silver nitrate, hydrog...
4B.12-4B.14 - Chlorine, Halides And Halogen PredictionsThis lesson uses oxidation numbers to make sense of chlorine reactions with water and alkali, the formation and reactions of halides, and the predictions that follow from Group 7 trends. It deliberately leaves the aqueous displacement pattern of Cl2, Br2 and I2 to the previous lesson, and the wid...
4C.15 - Inorganic Ion AnalysisThis lesson covers the required Edexcel 9CH0 tests for carbonate, hydrogencarbonate, sulfate and ammonium ions, with observations linked to ionic equations. Halide tests and Group 1/2 metal-ion tests are deliberately left to their own Topic 4 lessons, so they appear here only as boundaries, not n...
Topic 5: Formulae, Equations and Amounts of Substance
Topic 6: Organic Chemistry I
Topic 7: Modern Analytical Techniques I
Topic 8: Energetics I
Topic 9: Kinetics I
Topic 10: Equilibrium I
Advanced Chemistry (Topics 11-19)
Topic 11: Equilibrium II
Topic 12: Acid-base Equilibria
Topic 13: Energetics II
Topic 14: Redox II
Topic 15: Transition Metals
Topic 16: Kinetics II
Topic 17: Organic Chemistry II
Topic 18: Organic Chemistry III
Topic 19: Modern Analytical Techniques II