Exit to The mole concept and stoichiometry

Stoichiometry topic check

Check H1 Chemistry mole ratios, formulae, redox equations and reacting quantities, with targeted practice on mass, gas and solution calculations.

  • GCE A-Level H1 Chemistry 2027
Learning goals
  • Define relative atomic, isotopic, molecular and formula mass
  • Define the mole using the Avogadro constant
  • Calculate an element's relative atomic mass from the abundances of its isotopes
  • Define empirical formula and molecular formula
  • Calculate empirical and molecular formulae from combustion data or composition by mass
  • Write balanced equations
  • Describe and explain redox as electron transfer or a change in oxidation number, using Fe³⁺/Fe²⁺ and MnO₄⁻/Mn²⁺
  • Combine half-equations into a redox equation
  • Calculate reacting masses from formulae and equations using the mole concept
  • Calculate gas volumes in reactions, such as burning hydrocarbons, using the mole concept
  • Calculate volumes and concentrations of solutions using the mole concept, to the significant figures asked for
  • Deduce stoichiometric relationships from mole calculations

Your next step

Check what you know

Answer each question and say how sure you are to find what to practise next.

About 8 minutes

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Finding your next step…

Check what you know

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Practise

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About 10 minutes

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Practise after feedback

After a check, practise the skills it showed you need to work on.

About 10 minutes

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Check your progress

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Check again

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About 10 minutes

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Review

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Practise: multiple-choice

Practise questions on the skills you are learning.

About 10 minutes

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Practise: written

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