Mole calculations sim
Every route goes through moles.
Mole calculations · covers the GCSE, IGCSE, O-Level topic
What the sim shows
Every route goes through moles. Mass: n = mass ÷ Mᵣ and mass = n × Mᵣ, where Mᵣ is the sum of the Aᵣ of every atom in the formula (a number after a bracket multiplies everything inside it; the water after a dot is added on). Particles: number = n × L, with L = 6.02 × 10²³ per mole; ask particles of what. Gas: V = n × 24 with V in dm³ at r.t.p., for gases only. Solution: n = c × V with V in dm³, so cm³ ÷ 1000. Dilution keeps the moles, so c₁V₁ = c₂V₂. From an equation: into moles, across by the balancing numbers, back out. The limiting reactant gives the smaller answer when each amount is divided by its balancing number. Empirical formula: mass ÷ Aᵣ, divide by the smallest, then multiply by a small whole number if a ratio is not within 0.1 of a whole number. % yield = actual ÷ theoretical × 100; % purity = pure ÷ sample × 100. The Aᵣ values are the lessons'; answers are checked to 2 or 3 significant figures, and only the final answer is rounded.
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