Topic 5
Formulae, Equations
& Amounts of Substance
Topic 5 builds the calculation and chemical language foundation for A Level Chemistry. It covers atoms, elements, ions, molecules, compounds, empirical formulae, molecular formulae, balanced equations, reacting masses, solution concentrations, gas volumes, titration calculations, percentage yield, atom economy, measurement uncertainty, errors, risks and hazards.
Revision Notes
Elements
& Molecules
Atoms, Elements and Molecules
Key definitions including atom, element, ion, molecule, compound, empirical formula and molecular formula.
Start revising& Reaction
Types
Equations and Reaction Types
Balanced equations, ionic equations, state symbols, acid reactions and precipitation reactions.
Start revisingCalculations
Mole Calculations
The mole, Avogadro constant, molar mass, reacting masses, percentage yield and atom economy.
Start revising& Molecular
Formulae
Empirical and Molecular Formulae
Using experimental data, percentage composition and molar mass to calculate empirical and molecular formulae.
Start revising& Gases
Calculations with Solutions and Gases
Concentrations, titration calculations, molar volume and reacting volumes of gases.
Start revisingUncertainty
& Errors
Measurement Uncertainty and Errors
Measurement errors, percentage uncertainty, sources of error and minimising uncertainty in practical work.
Start revisingHazards
& Precautions
Risks, Hazards and Practical Precautions
Understanding hazards, evaluating risks and suggesting appropriate precautions in practical procedures.
Start revisingTopic 5 Formulae, Equations and Amounts of Substance – Edexcel A Level Chemistry
The following specification points outline the knowledge and skills students are expected to demonstrate for Topic 5. Ideas from this topic are applied across quantitative chemistry, practical work and later physical, inorganic and organic topics.