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Topic 2 · Inorganic chemistry

The behaviour of real substances: Group 1 and Group 7 trends, the gases in air, the reactivity series and rusting, extracting metals, acids and alkalis, salt preparation and the chemical tests.

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19 lessons, covering 50 specification statements.

What you need to know — the 50 statements, and where each one is taught

Every statement this topic carries, in the specification's own numbering, with Incandio's restatement of what it asks and the lesson that discharges it. Tick them off against your own copy of the specification: this is the topic's revision checklist, not a summary of it. Incandio is aligned to this specification. It is not published by, endorsed by or affiliated with Pearson, and it reproduces none of Pearson's wording — the statement numbers are given so you can check every lesson against your own copy.

Statement	What it asks	Taught in
2.1	How similarities in the reactions of Li, Na and K with water make them a family	Group 1 — the Alkali Metals
2.2	How differences in their reactions with air and water show the Group 1 reactivity trend	Group 1 — the Alkali Metals
2.3	Using the Group 1 trend to predict the properties of other alkali metals	Group 1 — the Alkali Metals
2.4	Explaining the Group 1 reactivity trend in terms of electronic configuration	Group 1 — the Alkali Metals
2.5	Colours, physical states and trends in physical properties of chlorine, bromine and iodine	Group 7 — the Halogens
2.6	Using the Group 7 trend to predict the properties of other halogens	Group 7 — the Halogens
2.7	How halogen–halide displacement reactions show the Group 7 reactivity trend	Group 7 — the Halogens
2.8	Explaining the Group 7 reactivity trend in terms of electronic configuration	Group 7 — the Halogens
2.9	The approximate percentages by volume of the four most abundant gases in dry air	The Gases in the Air
2.10	Determining the percentage of oxygen in air using reactions of metals and non-metals	The Gases in the Air
2.14 (practical)	Practical: determine the approximate percentage by volume of oxygen in air	The Gases in the Air
2.11	The combustion of magnesium, hydrogen and sulfur in oxygen	Combustion and Carbonates
2.12	Formation of carbon dioxide by thermal decomposition of metal carbonates	Combustion and Carbonates
2.13	Carbon dioxide as a greenhouse gas contributing to climate change	Combustion and Carbonates
2.15	Arranging metals in a reactivity series from their reactions with water and dilute acid	The Reactivity Series
2.16	Arranging metals in a reactivity series from displacement reactions	The Reactivity Series
2.17	The order of reactivity of the eleven metals named by the specification	The Reactivity Series
2.18	The conditions under which iron rusts	Rusting and its Prevention
2.19	Preventing rusting by barrier methods, galvanising and sacrificial protection	Rusting and its Prevention
2.20	Oxidation, reduction, redox, oxidising agent and reducing agent in terms of oxygen and electrons	Redox
2.21 (practical)	Practical: investigate reactions between dilute acids and metals	Redox
2.22	Most metals are extracted from ores; unreactive metals occur uncombined	Extracting Metals from their Ores
2.23	How extraction method relates to position in the reactivity series (carbon for iron, electrolysis for aluminium)	Extracting Metals from their Ores
2.24	Commenting on a metal extraction process from given information	Extracting Metals from their Ores
2.25	Explaining the uses of aluminium, copper, iron and steel from their properties	Uses of Metals, and Alloys
2.26	An alloy as a mixture of a metal with one or more other elements	Uses of Metals, and Alloys
2.27	Why alloys are harder than pure metals	Uses of Metals, and Alloys
2.28	Using litmus, phenolphthalein and methyl orange to distinguish acids from alkalis	Acids, Alkalis and the pH Scale
2.29	Using the pH scale to classify solutions from strongly acidic to strongly alkaline	Acids, Alkalis and the pH Scale
2.30	Using universal indicator to measure approximate pH	Acids, Alkalis and the pH Scale
2.31	Acids as a source of hydrogen ions and alkalis as a source of hydroxide ions in solution	Hydrogen Ions and Neutralisation
2.32	Alkalis neutralise acids	Hydrogen Ions and Neutralisation
2.33	How to carry out an acid–alkali titration	Titrations
2.40	Preparing a pure dry soluble salt from an acid and an alkali	Titrations
2.34	The general solubility rules for ionic compounds in water	Solubility Rules and Proton Transfer
2.35	Acids and bases in terms of proton transfer	Solubility Rules and Proton Transfer
2.36	An acid as a proton donor and a base as a proton acceptor	Solubility Rules and Proton Transfer
2.37	Reactions of hydrochloric, sulfuric and nitric acids with metals, bases and carbonates	The Reactions of Acids
2.38	Metal oxides, metal hydroxides and ammonia as bases; alkalis as soluble bases	The Reactions of Acids
2.39	Preparing a pure dry soluble salt from an insoluble reactant	Preparing a Soluble Salt
2.42 (practical)	Practical: prepare pure dry hydrated copper(II) sulfate crystals from copper(II) oxide	Preparing a Soluble Salt
2.41	Preparing a pure dry insoluble salt from two soluble reactants	Preparing an Insoluble Salt
2.43 (practical)	Practical: prepare a pure dry sample of lead(II) sulfate	Preparing an Insoluble Salt
2.44	Tests for hydrogen, oxygen, carbon dioxide, ammonia and chlorine	Tests for Gases, and for Water
2.49	The test for water using anhydrous copper(II) sulfate	Tests for Gases, and for Water
2.50	A physical test to show whether a sample of water is pure	Tests for Gases, and for Water
2.45	How to carry out a flame test	Flame Tests
2.46	Flame colours for Li⁺, Na⁺, K⁺, Ca²⁺ and Cu²⁺	Flame Tests
2.47	Tests for NH₄⁺, Cu²⁺, Fe²⁺ and Fe³⁺ using sodium hydroxide solution	Tests for Ions
2.48	Tests for halide ions, sulfate ions and carbonate ions	Tests for Ions

The lessons

Group 1 — the Alkali Metals — Metals soft enough to cut with a knife, which set fire to water — and get worse as you go down. (2.1, 2.2, 2.3, 2.4)
Group 7 — the Halogens — A green gas, a brown liquid and a grey solid — and a trend that runs the opposite way to Group 1. (2.5, 2.6, 2.7, 2.8)
The Gases in the Air — Four gases, one of which is doing almost all the chemistry — and how to measure it without ever touching it. (2.9, 2.10, 2.14)
Combustion and Carbonates — Three things burning in oxygen, one carbonate breaking apart, and the 0.04% gas that changes the climate. (2.11, 2.12, 2.13)
The Reactivity Series — Putting eleven metals in order by watching what each one will and will not do. (2.15, 2.16, 2.17)
Rusting and its Prevention — Two things are needed to rust iron, and every method of stopping it removes one of them — or cheats. (2.18, 2.19)
Redox — The same reaction described twice — once by what gains oxygen, and once by what loses electrons. (2.20, 2.21)
Extracting Metals from their Ores — Where a metal sits in the reactivity series decides how much trouble it takes to get it out. (2.22, 2.23, 2.24)
Uses of Metals, and Alloys — Why each metal is used where it is — and why almost none of them is used pure. (2.25, 2.26, 2.27)
Acids, Alkalis and the pH Scale — Three indicators that answer a yes-or-no question, and one scale that answers 'how much'. (2.28, 2.29, 2.30)
Hydrogen Ions and Neutralisation — What every acid has in common, what every alkali has in common, and why every neutralisation is one equation. (2.31, 2.32)
Titrations — Finding the exact volume that neutralises — and then making the salt again without the indicator in it. (2.33, 2.40)
Solubility Rules and Proton Transfer — Which salts dissolve, and the broader definition of an acid that explains why ammonia counts. (2.34, 2.35, 2.36)
The Reactions of Acids — Three things acids react with, three sets of products, and one test that identifies a carbonate instantly. (2.37, 2.38)
Preparing a Soluble Salt — Add too much on purpose, filter the excess away, and crystallise what is left. (2.39, 2.42)
Preparing an Insoluble Salt — Mix two solutions, and the salt you want falls out of them as a solid. (2.41, 2.43)
Tests for Gases, and for Water — Five gases, five tests — and the difference between something being water and being pure water. (2.44, 2.49, 2.50)
Flame Tests — Five metal ions that announce themselves by the colour they give a flame. (2.45, 2.46)
Tests for Ions — Sodium hydroxide identifies four cations by the colour of what falls out — and three anion tests complete the set. (2.47, 2.48)

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