The Periodic Table: chemical periodicity: past paper questions

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• Question 17May/June 2026, paper 11Multiple choice1 markHas a diagram

  The table contains some statements about Period 3 elements and their compounds. In which row are both statements correct?

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• Question 5Oct/Nov 2025, paper 11Multiple choice1 mark

  Which statement explains why sodium and potassium have different melting points?

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• Question 6Oct/Nov 2024, paper 11Multiple choice1 markHas a diagram

  The graphs show trends in four physical properties of elements in Period 3, excluding argon.

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• Question 16Oct/Nov 2023, paper 11Multiple choice1 mark

  X, Y and Z are elements all found within Groups 13, 14 and 15 of the Periodic Table. X is in the same group in the Periodic Table as Y. Y and Z are in Period 3.

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• Question 18May/June 2026, paper 11Multiple choice1 mark

  Which statement explains why silicon has the highest melting point of the elements of Period 3?

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• Question 16Oct/Nov 2025, paper 11Multiple choice1 markHas a diagram

  The atomic radii and ionic radii for three elements in Period 3 are shown.

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• Question 16Oct/Nov 2024, paper 11Multiple choice1 markHas a diagram

  What are the acid–base nature and structure of ${\text{SO}}_2$?

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• Question 17Oct/Nov 2023, paper 11Multiple choice1 mark

  Which row about silicon, Si, and magnesium, Mg, and their ions is correct?

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• Question 16May/June 2026, paper 12Multiple choice1 mark

  Which statement about the Period 3 elements sodium to phosphorus and their compounds is correct?

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• Question 17Oct/Nov 2025, paper 11Multiple choice1 mark

  Three equations are listed. $x$, $y$ and $z$ are all whole numbers.

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• Question 17Oct/Nov 2024, paper 11Multiple choice1 markHas a diagram

  Elements X and Y are in Period 3 of the Periodic Table. Element X is either phosphorus or sulfur. Element Y is either sodium or magnesium.

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• Question 18Oct/Nov 2023, paper 11Multiple choice1 markHas a diagram

  Bromocresol green is an acid-base indicator. Below a pH of 3.8 it is yellow. Above a pH of 5.4 it is blue.

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• Question 17May/June 2026, paper 12Multiple choice1 markHas a diagram

  X, Y and Z are elements in Period 3. Some physical properties of X, Y and Z are shown.

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• Question 18Oct/Nov 2025, paper 11Multiple choice1 mark

  Which oxide has a simple structure rather than a giant structure?

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• Question 18Oct/Nov 2024, paper 11Multiple choice1 mark

  Q is a semi-conductor. The chloride of Q reacts with water to form white fumes and an acidic solution. Which Period 3 element is Q?

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• Question 10Oct/Nov 2023, paper 12Multiple choice1 markHas a diagram

  In the structure of solid ${\text{SiO}}_2$ each silicon atom is bonded to x oxygen atoms each oxygen atom is bonded to y silicon atoms each bond is a z type bond. What is the correct combination of x, y and z in these statements?

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• Question 19May/June 2026, paper 12Multiple choice1 mark

  The chloride of element J is added to a beaker of water. The oxide of element J is then added to the same beaker.

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• Question 7Oct/Nov 2025, paper 12Multiple choice1 markHas a diagram

  $\text{X}$ and $\text{Y}$ are different elements in Period 3. Atoms of $\text{X}$ and $\text{Y}$ each have only one completely filled orbital in their highest occupied energy sub-shell. $\text{Y}$ has a greater first ionisation energy than $\text{X}$.

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• Question 17Oct/Nov 2024, paper 12Multiple choice1 mark

  Which oxide is insoluble in aqueous sodium hydroxide?

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• Question 18Oct/Nov 2023, paper 12Multiple choice1 markHas a diagram

  Which row gives the best description of the variations in the melting points and the first ionisation energies of the elements in Period 3 from sodium to argon?

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• Question 16May/June 2026, paper 13Multiple choice1 mark

  Elements W, X, Y and Z are different elements in Period 3 of the Periodic Table. Four statements about W, X, Y and Z are given. 1 X has the greatest electronegativity value of the four elements.

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• Question 17Oct/Nov 2025, paper 12Multiple choice1 markHas a diagram

  Sodium and sulfur react together to form sodium sulfide, ${\text{Na}}_2\text{S}$. How do the atomic radius and ionic radius of sodium compare with those of sulfur?

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• Question 18Oct/Nov 2024, paper 12Multiple choice1 markHas a diagram

  Sodium and sulfur are burned separately in oxygen. Each reaction has a distinctive coloured flame. Which row is correct?

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• Question 19Oct/Nov 2023, paper 12Multiple choice1 mark

  X and Y are atoms of different elements in Period 3 of the Periodic Table. Neither X nor Y is argon. X is a non-metal.

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• Question 17May/June 2026, paper 13Multiple choice1 markHas a diagram

  The table shows the melting points of ${\text{SiO}}_2$ and ${\text{P}}_4{\text{O}}_6$.

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• Question 18Oct/Nov 2025, paper 12Multiple choice1 mark

  Compound $\text{X}$ is an oxide of a Period 3 element. Compound $\text{X}$ is a white solid at $25{}^{\circ }\text{C}$. It reacts with water to form an acidic solution.

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• Question 19Oct/Nov 2024, paper 12Multiple choice1 markHas a diagram

  X and Y are elements in Period 3 of the Periodic Table. Y has a greater atomic number than X. The stable ion formed by Y has a greater radius than the stable ion formed by X. The stable ion formed by Y has 18 electrons. Which row is correct?

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• Question 20Oct/Nov 2023, paper 12Multiple choice1 mark

  Four mixtures are added to four separate $50{\text{ cm}}^3$ samples of water and stirred. Which mixture results in a solution with the highest pH?

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• Question 1May/June 2026, paper 22Structured14 marks

  Oxygen reacts with many elements. State the total number of electrons that occupy the 2p sub-shell in an oxygen atom.

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• Question 23Oct/Nov 2025, paper 12Multiple choice1 mark

  Element $\text{E}$ is in Period 3. It forms a chloride which reacts with a small amount of water to produce a white precipitate and steamy fumes. This precipitate is soluble in $\text{NaOH(aq)}$ and in $\text{HCl(aq)}$.

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