Chemistry Paper 2
AQA Combined Science Higher. Counted from 4 real June exams: 2018, 2019, 2023 and 2024, 280 marks in all.
Every topic on the specification can be examined, including ones listed here as not examined.
| Topic | How often | Share of marks |
|---|---|---|
| Potable water | Came up 4 of the last 4 years | 8% of marks |
| Calculating rates of reactions | Came up 4 of the last 4 years | 8% of marks |
| Chromatography | Came up 3 of the last 4 years | 7% of marks |
| Catalysts | Came up 3 of the last 4 years | 5% of marks |
| Fractional distillation and petrochemicals | Came up 4 of the last 4 years | 5% of marks |
| Atmospheric pollutants from fuels | Came up 3 of the last 4 years | 5% of marks |
| Alternative methods of extracting metals | Came up 2 of the last 4 years | 4% of marks |
| Factors which affect the rates of chemical reactions | Came up 3 of the last 4 years | 3% of marks |
| Crude oil, hydrocarbons and alkanes | Came up 3 of the last 4 years | 3% of marks |
| Cracking and alkenes | Came up 3 of the last 4 years | 2% of marks |
| Equilibrium | Came up 3 of the last 4 years | 2% of marks |
| Human activities which contribute to an increase in greenhouse gases in the atmosphere | Came up 3 of the last 4 years | 2% of marks |
| Formulations | Came up 3 of the last 4 years | 2% of marks |
| Greenhouse gases | Came up 2 of the last 4 years | 2% of marks |
| Concentration of solutions | Came up 1 of the last 4 years | 2% of marks |
| Collision theory and activation energy | Came up 3 of the last 4 years | 2% of marks |
| How carbon dioxide decreased | Came up 3 of the last 4 years | 2% of marks |
| Properties and effects of atmospheric pollutants | Came up 2 of the last 4 years | 2% of marks |
| Global climate change | Came up 2 of the last 4 years | 2% of marks |
| Moles | Came up 2 of the last 4 years | 2% of marks |
| The carbon footprint and its reduction | Came up 2 of the last 4 years | 2% of marks |
| Properties of hydrocarbons | Came up 3 of the last 4 years | 2% of marks |
| Life cycle assessment | Came up 2 of the last 4 years | 2% of marks |
| Properties of ionic compounds | Not examined since 20181 of the last 4 years | 1% of marks |
| The effect of pressure changes on equilibrium | Came up 3 of the last 4 years | 1% of marks |
| Test for oxygen | Came up 2 of the last 4 years | 1% of marks |
| Test for chlorine | Came up 2 of the last 4 years | 1% of marks |
| Atoms, elements and compounds | Came up 3 of the last 4 years | 1% of marks |
| Pure substances | Came up 3 of the last 4 years | 1% of marks |
| How oxygen increased | Came up 2 of the last 4 years | 1% of marks |
| The effect of changing conditions on equilibrium | Came up 2 of the last 4 years | 1% of marks |
| The effect of changing concentration | Came up 3 of the last 4 years | 1% of marks |
| The effect of temperature changes on equilibrium | Came up 3 of the last 4 years | 1% of marks |
| Limiting reactants | Came up 2 of the last 4 years | 1% of marks |
| Reversible reactions | Came up 2 of the last 4 years | 1% of marks |
| Test for hydrogen | Came up 1 of the last 4 years | 1% of marks |
| The Earth's early atmosphere | Not examined since 20181 of the last 4 years | 1% of marks |
| Using the Earth's resources and sustainable development | Came up 1 of the last 4 years | 1% of marks |
| Ways of reducing the use of resources | Not examined since 20181 of the last 4 years | 1% of marks |
| Relative formula mass | Came up 1 of the last 4 years | under 1% of marks |
| Amounts of substances in equations | Came up 1 of the last 4 years | under 1% of marks |
| The three states of matter | Came up 1 of the last 4 years | under 1% of marks |
| Reactions of acids with metals | Came up 1 of the last 4 years | under 1% of marks |
| Energy changes and reversible reactions | Came up 1 of the last 4 years | under 1% of marks |
| Covalent bonding | Came up 1 of the last 4 years | under 1% of marks |
| The proportions of different gases in the atmosphere | Came up 1 of the last 4 years | under 1% of marks |
| Test for carbon dioxide | Not examined in the last 4 years | |
| Waste water treatment | Not examined in the last 4 years |
Required practicals
2018 and 2019 mark schemes rarely name the practical, so those years are undercounted here.
| Topic | How often | Share of marks |
|---|---|---|
| investigate how paper chromatography can be used to separate and tell the difference between coloured substances | Came up 2 of the last 4 years | 2% of marks |
| investigate how changes in concentration affect the rates of reactions by a method involving measuring the volume of a gas produced and a method involving a | Came up 1 of the last 4 years | 2% of marks |
| analysis and purification of water samples from different sources, including pH, dissolved solids and distillation | Came up 2 of the last 4 years | 2% of marks |