0654.C3.3.05 — Calculate stoichiometric reacting masses, limiting reactants, volumes of gases at r.t.p., including conversion between cm3 and dm3: past paper questions
Real questions on 0654.c3.3.05 — calculate stoichiometric reacting masses, limiting reactants, volumes of gases at r.t.p., including conversion between cm3 and dm3
The newest 7 of 7 written questions. Open one to see it on the real paper.
- 0654/02 · Specimen 2025 · Q15[1]
What is the mass of hydrogen chloride that reacts with 5.1 g of ammonia?
See it on the paper → - 0654/02 · Specimen 2025 · Q16[1]
Which row shows the volume of oxygen used and the volume of carbon dioxide produced in the reaction?
See it on the paper → - 0654/43 · October/November 2025 · Q8c(ii)[2]
The calcium oxide reacts with silicon dioxide, SiO 2 , which is an impurity in the iron ore, to make calcium silicate. CaO + SiO 2 CaSiO 3 Calculate the minimum mass of calcium oxide needed to remove 720 tonnes of silicon dioxide. [A r : Ca, 40; O, 16; Si, 28] mass of calcium oxide = tonnes
See it on the paper → - 0654/41 · May/June 2025 · Q6f[3]
Some coal burns to make 11 000 g of carbon dioxide gas. Calculate the volume occupied by 11 000 g of carbon dioxide gas. The volume of one mole of any gas is 24 dm 3 at room temperature and pressure (r.t.p.). [A r : C, 12; O, 16] volume of carbon dioxide gas = dm 3
See it on the paper → - 0654/41 · May/June 2025 · Q8c[3]
A mixture containing 5.6 g of ethene, C 2 H 4 , is allowed to react with 5.4 g of steam. Ethanol, C 2 H 5 OH, is made. C 2 H 4 + H 2 O C 2 H 5 OH Determine the limiting reactant in this reaction. Show your working. [A r : C, 12; H, 1; O, 16]
See it on the paper → - 0654/43 · May/June 2025 · Q8e[2]
The reaction makes sodium chloride solution, water and carbon dioxide. Complete the state symbols in the balanced chemical equation.
See it on the paper → - 0654/42 · February/March 2025 · Q7c[3]
Butene also reacts with hydrogen to form butane, C 4 H 10 . Calculate the maximum mass of butane that can be made from 1.68 kg of butene. [A r : C, 12; H, 1] mass of butane = kg C 4 H 10 C 4 H 8 + H 2
See it on the paper →
What examiners said
The correct answer of 6000 dm3 was frequently seen. The majority of candidates correctly calculated the Mr of CO2 as 44.
— Examiner report, May/June 2025, 0654/41 Q6(f) (Cambridge)
Many responses correctly calculated the moles of ethene and steam and clearly displayed the working. The majority of candidates then went on to identify the correct limiting reactant. Some candidates calculated the molecular mass and just compared these, deducing that steam was the limiting reactant as it had less mass.
— Examiner report, May/June 2025, 0654/41 Q8(c) (Cambridge)
State symbols were quite well known. Common incorrect responses had sodium chloride as a solid and water as aqueous or gaseous. Some put numbers into the state symbol brackets.
— Examiner report, May/June 2025, 0654/43 Q8(e) (Cambridge)
Past papers, syllabus and examiner reports © UCLES (Cambridge University Press & Assessment). Questions are matched to topics from the official syllabus. AssessPro is independent and not endorsed by Cambridge.