IGCSE Edexcel Moles

moles of gases =

• conc x vol

• vol/24 (in dm³)

• vol/24 (in cm³)

• mass/Mr

moles of a solid =

• mass/Mr

• mass x Mr

• vol/conc

• vol x conc

Moles of a solution =

• conc x vol

• vol/conc

• conc/vol

• vol x 24000

Volume of a solution =

• moles x conc

• mol/conc

• conc/mol

• moles x 24 (in dm³)

volume of a gas =

• 24 000 cm³ x moles

• 24 cm³ x moles

• 24 dm³ / moles

• moles / 24dm³

What volume does 6 moles of methane occupy in cm³? (units not required in answer)

What is the mass of 6dm³ of chlorine in grams? (units not required in answer.

Find the volume of H₂O gas formed (at room temperature and pressure, in cm³) when 11.0 g of propane burns in oxygen. (Units not required in answer)

C₃H₈(g) + 5O₂(g) -> 3CO₂(g) + 4H₂O(l)

591.5g of hydrated potassium manganate crystals (KMnO4.nH2O) gave 276.5g of anhydrous potassium manganate on heating to constant mass. Work out the formula mass of the hydrated potassium manganate and so the value of n.

KMnO₄.nH₂O → KMnO₄ + n H₂O

25.0 cm³ of sodium carbonate solution neutralises 26.2 cm³ of 0.550 mol/dm³ nitric acid solution.

2 HNO₃(aq) + Na₂CO₃(aq) → 2 NaNO₃(aq) + CO₂(aq) + 2 H₂O(l)

Calculate the concentration of sodium carbonate, giving your answer to a suitable level of precision. (units are not required in the answer).