Formulae: past paper questions
Real questions on formulae
The newest 20 of 123 written questions. Open one to see it on the real paper.
- 0620/31 · May/June 2026 · Q6e[2]
Cobalt forms a compound with the nitrate ion. The formula of the compound is Co(NO 3 ) 2 . Complete Table 6.1 to calculate the relative formula mass of Co(NO 3 ) 2 . Table 6.1 type of atom number of atoms relative atomic mass 1 59 cobalt nitrogen 14 oxygen 16 1 × 59 = 59 relative formula mass =
See it on the paper → - 0620/32 · May/June 2026 · Q6e[2]
Nickel( II ) hydroxide has the formula Ni(OH) 2 . Complete Table 6.1 to calculate the relative formula mass of Ni(OH) 2 . Table 6.1 type of atom relative atomic mass 1 59 nickel oxygen 16 hydrogen 1 1 × 59 = 59 relative formula mass = number of atoms
See it on the paper → - 0620/33 · May/June 2026 · Q6e[2]
Titanium forms a compound with the nitrate ion. The formula of the compound is Ti(NO 3 ) 2 . Complete Table 6.1 to calculate the relative formula mass of Ti(NO 3 ) 2 . type of atom number of atoms relative atomic mass 1 48 titanium nitrogen 14 oxygen 16 1 × 48 = 48 relative formula mass = Table 6.1
See it on the paper → - 0620/43 · May/June 2026 · Q7c[3]
Organic compound D has the following composition by mass. C, 88.9%; H, 11.1% Calculate the empirical formula of compound D. empirical formula =
See it on the paper → - 0620/61 · May/June 2026 · Q1a(ii)[1]
Explain why the copper( II ) carbonate must be added in excess.
See it on the paper → - 0620/63 · May/June 2026 · Q4[6]
Rhubarb plant leaves contain oxalic acid. Oxalic acid is soluble in water. Acidified aqueous potassium manganate( VII ) changes from purple to colourless when it reacts with oxalic acid. Plan an experiment to find which of two rhubarb plant leaves, A and B, contains the highest concentration of oxalic acid. You are pro...
See it on the paper → - 0620/42 · February/March 2026 · Q4f[1]
Ethanol is a common fuel. Methanol can also be used as a fuel. Complete and balance the symbol equation for the incomplete combustion of methanol, CH 3 OH. CH 3 OH + CO + H 2 O
See it on the paper → - 0620/31 · October/November 2025 · Q4c[2]
A different molecule found in plants has the molecular formula C 11 H 14 O 3 . Complete Table 4.1 to calculate the relative molecular mass of C 11 H 14 O 3 . Table 4.1 type of atom number of atoms relative atomic mass carbon 11 12 hydrogen 1 oxygen 16 11 × 12 = 132 relative molecular mass =
See it on the paper → - 0620/31 · October/November 2025 · Q8b(ii)[1]
the total volume of H 2 produced when the reaction is complete.
See it on the paper → - 0620/32 · October/November 2025 · Q4c[2]
A different molecule found in plants has the molecular formula C 10 H 16 O 2 . Complete Table 4.1 to calculate the relative molecular mass of C 10 H 16 O 2 . Table 4.1 type of atom number of atoms relative atomic mass carbon 10 12 hydrogen 1 oxygen 16 10 × 12 = 120 relative molecular mass =
See it on the paper → - 0620/32 · October/November 2025 · Q8a[1]
Use Fig. 8.1 to determine the total volume of H 2 S produced when the reaction is complete. total volume of H 2 S = cm 3
See it on the paper → - 0620/41 · October/November 2025 · Q3a[2]
Complete the symbol equation for the reaction. Include state symbols.
See it on the paper → - 0620/41 · October/November 2025 · Q3c[1]
Calculate the concentration of NaOH(aq) used in step 1. concentration of NaOH(aq) = mol / dm 3
See it on the paper → - 0620/41 · October/November 2025 · Q3e[2]
Calculate the volume of H 2 SO 4 (aq), in cm 3 , added in step 3. volume of H 2 SO 4 (aq) = cm 3
See it on the paper → - 0620/41 · October/November 2025 · Q5b(ii)[2]
Write the symbol equation for the reaction in method 1. (ii)
See it on the paper → - 0620/41 · October/November 2025 · Q5b(iii)[2]
Write the symbol equation for the reaction in method 2.
See it on the paper → - 0620/41 · October/November 2025 · Q5c(ii)[1]
Butane-1,4-diol reacts with ethanoic acid. Determine the number of moles of ethanoic acid which react fully with one mole of butane-1,4-diol.
See it on the paper → - 0620/42 · October/November 2025 · Q3b[2]
mass = g (b) Calculate the mass of solid BaCl 2 dissolved in step 1.
See it on the paper → - 0620/62 · October/November 2025 · Q1b(iii)[2]
After washing the residue, the student dries the residue in an oven. The student then measures the mass of the dry residue. The masses the student records are shown in Table 1.1. Table 1.1 mass of small pieces of eggshell / g 2.00 mass of dry residue after filtration / g 0.11 Use the data in Table 1.1 to calculate the...
See it on the paper → - 0620/31 · May/June 2025 · Q2a(ii)[1]
The total mass of compounds formed from 1000 cm 3 of sea water is 19.0 g. Calculate the total mass of compounds formed from 1750 cm 3 of sea water. mass = g
See it on the paper →
What examiners said
Comprehensive responses • Most candidates completed and balanced the equation. Limited responses • A few candidates gave an incorrect reactant.
— Examiner report, February/March 2026, 0620/42 Q4(f) (Cambridge)
Candidates should be reminded to give all numerical answers in the decimal format. Some calculators produce answers as fractions e.g. 133/4 which are not accepted.
— Examiner report, May/June 2025, 0620/31 Q2(a)(ii) (Cambridge)
The use of a formula with brackets caused significant confusion. Many candidates did not know what they represented and frequently multiplied all the numbers together. Some candidates confused atomic mass and atomic number. The contribution of aluminium atoms to the relative mass was often correct.
— Examiner report, May/June 2025, 0620/31 Q3(c) (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.