Contents
Independent final check
Explain without the key
state / explain
Final check
Supplement. (a) State what is meant by one mole of a substance. (b) 32 g of oxygen, O2, and 23 g of sodium, Na, contain the same number of particles. Explain why. (Ar: O 16, Na 23.)
state: give a concise answer. explain: give reasons and connect them to evidence.
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Scope and sources
Cambridge IGCSE Chemistry 0620 · 2026–2028 v2 · Original learning materials.
The mole (3.3 Core 1, Supplement 2, 3 and part of 5): concentration in g/dm³ and mol/dm³, the mole and the Avogadro constant, n = m/M for amount, mass, molar mass, relative mass and number of particles, and the volumes and concentrations of solutions with cm³ and dm³. Molar gas volume, reacting masses and gas volumes from equations, limiting reactants, empirical and molecular formulae, percentage yield and purity, and titration are left to other modules.
Apparatus, amounts and times in the experiment are illustrative. Real practical work follows a teacher-approved safety method.
Official Cambridge syllabus