Relative masses of atoms and molecules: past paper questions

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• Question 11May/June 2026, paper 11Multiple choice1 mark

  Which formula gives the $M_{\mathrm{r}}$ of lead(II) bromide?

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• Question 11Oct/Nov 2025, paper 12Multiple choice1 mark

  What is the relative formula mass of calcium sulfate, ${\text{CaSO}}_4$?

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• Question 8Oct/Nov 2024, paper 11Multiple choice1 mark

  What is the relative molecular mass, $M_{\text{r}}$, of sulfuric acid, ${\text{H}}_2{\text{SO}}_4$?

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• Question 9Oct/Nov 2023, paper 12Multiple choice1 mark

  The formula of a compound containing element X is ${\mathrm{N}\mathrm{a}}_2{\mathrm{X}}_2{\mathrm{O}}_3$. The relative formula mass of the compound is 158. What is the relative atomic mass of X?

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• Question 10May/June 2026, paper 13Multiple choice1 mark

  What is the relative formula mass of ammonium nitrate, ${\mathrm{N}\mathrm{H}}_4{\mathrm{N}\mathrm{O}}_3$?

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• Question 11Oct/Nov 2025, paper 13Multiple choice1 mark

  What is the relative formula mass, $M_{\text{r}}$, of calcium hydroxide, ${\text{Ca(OH)}}_2$?

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• Question 10Oct/Nov 2024, paper 12Multiple choice1 mark

  What is the relative formula mass of magnesium bromide?

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• Question 9Oct/Nov 2023, paper 13Multiple choice1 mark

  Calcium nitrate has the formula ${\mathrm{C}\mathrm{a}(\mathrm{N}\mathrm{O}}_3{)}_2$. What is the relative formula mass, $M_r$, of calcium nitrate?

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• Question 6Oct/Nov 2025, paper 22Multiple choice1 markHas a diagram

  Which two values are used to calculate the relative atomic mass of a sample of boron?

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• Question 10Oct/Nov 2024, paper 13Multiple choice1 mark

  The isotope of which element is used to define the relative atomic mass of other elements?

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• Question 4Oct/Nov 2023, paper 22Multiple choice1 markHas a diagram

  The percentage abundances of three isotopes in a sample of neon are shown.

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• Question 8May/June 2026, paper 21Multiple choice1 mark

  The formula of a compound containing element $\text{Z}$ is ${\text{Na}}_2{\text{Z}}_2{\text{O}}_3$. The relative formula mass of the compound is $158$. What is the relative atomic mass of $\text{Z}$?

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• Question 35Oct/Nov 2024, paper 13Multiple choice1 markHas a diagram

  Which row gives the relative molecular mass, $M_{\text{r}}$, of the first member of the named homologous series?

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• Question 9May/June 2026, paper 22Multiple choice1 mark

  Which statement defines relative molecular mass?

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• Question 10May/June 2025, paper 11Multiple choice1 mark

  The equation shows the thermal decomposition of magnesium carbonate. $${\text{MgCO}}_3\to \text{MgO}+{\text{CO}}_2$$ [$M_r$: ${\text{MgCO}}_3$, 84] Which mass of magnesium oxide is formed when $21.0\text{ g}$ of magnesium carbonate is completely decomposed?

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• Question 7Oct/Nov 2023, paper 32Structured13 marksHas a diagram

  Fig. 7.1 shows the displayed formula of fumaric acid. On Fig. 7.1, draw a circle around one carboxylic acid functional group.

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• Question 9May/June 2025, paper 13Multiple choice1 mark

  The relative formula mass, $M_r$, of calcium carbonate, ${\text{CaCO}}_3$, is 100. What is the mass of carbon present in $100\text{ g}$ of calcium carbonate?

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• Question 4Oct/Nov 2024, paper 31Structured13 marksHas a diagram

  Fig. 4.1 shows the displayed formula of compound A. Explain why compound A is described as unsaturated.

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• Question 7Oct/Nov 2023, paper 33Structured13 marksHas a diagram

  Ethanoic acid and methacrylic acid are both carboxylic acids. Complete the word equation for the reaction of ethanoic acid with calcium.

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• Question 10May/June 2025, paper 13Multiple choice1 mark

  What is the definition of relative atomic mass?

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• Question 4Oct/Nov 2024, paper 33Structured13 marksHas a diagram

  Fig. 4.1 shows the displayed formula of compound A. Fig. 4.1 On Fig 4.1 draw a circle around the carboxylic acid functional group.

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• Question 2Oct/Nov 2024, paper 41Structured14 marks

  This question is about atomic structure and the Periodic Table. Define the term nucleon number.

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• Question 8May/June 2023, paper 12Multiple choice1 mark

  What is the relative formula mass of ${\mathrm{M}\mathrm{g}(\mathrm{O}\mathrm{H})}_2$?

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• Question 3May/June 2025, paper 31Structured11 marksHas a diagram

  This question is about sulfur and its compounds. Explain why sulfur is placed in Group VI of the Periodic Table.

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• Question 12May/June 2024, paper 12Multiple choice1 mark

  What is the definition of relative molecular mass, $M_r$?

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• Question 8May/June 2023, paper 13Multiple choice1 mark

  The compound magnesium nitrate has the formula ${\text{Mg(NO}}_3{)}_2$. What is the relative formula mass of magnesium nitrate?

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• Question 3May/June 2025, paper 32Structured11 marksHas a diagram

  This question is about phosphorus and its compounds. Phosphorus is in Group V of the Periodic Table. Explain why phosphorus is placed in this group.

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• Question 7May/June 2023, paper 22Multiple choice1 mark

  Which sample contains the largest number of molecules?

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• Question 4May/June 2025, paper 33Structured10 marksHas a diagram

  This question is about nitrogen and its compounds. Explain why nitrogen is in Group V of the Periodic Table.

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• Question 1May/June 2024, paper 22Multiple choice1 mark

  Which gas has the slowest rate of diffusion?

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