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O-Level Pure Chemistry: Mole Concept & Stoichiometry: Step-by-Step

By Intuitional Team1 min read

O-Level Pure Chemistry — Mole Concept & Stoichiometry: Step-by-Step: quick notes, common traps, and an exam-style example.

Mole concept

1 mol = 6.02 × 10²³ particles. n = m/Mr or n = V/24 dm³ (for gases at rtp).

Stoichiometry

Use balanced equations to get molar ratios. Always work in moles before converting to mass/volume.

Exam habits

  • Always show mole ratio step.
  • Convert cm³ to dm³ for gas volumes.
  • Box final answer with correct units.

Tags

O-LevelPure ChemistryMole Concept & Stoichiometry