What this tests
Syllabus point 3.3 — The mole and the Avogadro constant, in Stoichiometry. Difficulty medium (estimated from the question's demands, not a Cambridge rating).
Cambridge IGCSE Chemistry 0620 · 3.3 The mole and the Avogadro constant
November 2018 · Paper 22 · Question 8
One real Cambridge question from Stoichiometry, with the official answer.