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A Level H1 Chemistry Periodic Table Quiz

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A Level H1 Chemistry From Real Exams Generated by Gemma 4 31B Updated 2026-06-03

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Questions

A-Level Chemistry H1 Quiz - Periodic Table

Name: ____________________ Class: ____________________ Date: ____________________ Score: / 45

Duration: 60 Minutes
Total Marks: 45
Instructions: Answer all questions. Show all working for calculations. Use the Periodic Table provided in your data booklet.

Section A: Atomic Properties & Trends (Questions 1–7)

Define the term first ionisation energy. [2]
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Explain why the first ionisation energy of magnesium is higher than that of aluminium. [2]
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Compare the atomic radius of sodium (Na) and potassium (K). Explain your answer in terms of electronic structure. [2]
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Explain why the electronegativity of fluorine is higher than that of chlorine. [2]
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Describe the trend in the first ionisation energy across Period 3 from sodium to argon. [2]
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Why does the atomic radius decrease across a period from left to right? [2]
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Explain why the second ionisation energy of sodium is significantly higher than its first ionisation energy. [2]
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Section B: Period 3 Oxides & Elements (Questions 8–14)

Identify the Period 3 element that forms a sparingly soluble amphoteric oxide. [1]
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Write a balanced chemical equation, including state symbols, for the reaction of silicon(IV) oxide with hot concentrated sodium hydroxide. [2]
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Compare the melting points of sodium chloride (NaCl) and magnesium chloride (MgCl₂). Explain the difference. [3]
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Phosphorus(V) oxide ( $\text{P}_4\text{O}_{10}$ ) is a powerful dehydrating agent. Explain why it reacts vigorously with water. [2]
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State the formula and the nature (acidic/basic/amphoteric) of the oxide formed when sulfur reacts with oxygen. [2]
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Describe the change in the nature of oxides across Period 3 from sodium to chlorine. [2]
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Explain why $\text{Al}_2\text{O}_3$ is described as amphoteric. [2]
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Section C: Group Trends & Applications (Questions 15–20)

Predict the trend in the reactivity of Group 1 elements as you move down the group. Justify your answer. [3]
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Explain why the boiling point of helium is lower than that of neon. [2]
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(a) State the general formula for Group 17 halides. [1]
(b) Explain why hydrogen chloride ( $\text{HCl}$ ) is a gas while sodium chloride ( $\text{NaCl}$ ) is a solid at room temperature. [2]
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Compare the oxidizing power of fluorine and iodine. Explain your reasoning. [3]
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Describe the structure and bonding in solid aluminium. [2]
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An element X in Period 3 forms a chloride with the formula $\text{XCl}_3$ . (a) Identify element X. [1] (b) Predict the shape of the $\text{XCl}_3$ molecule and state the bond angle. [2]
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Answers

Answer Key - A-Level Chemistry H1 Quiz (Periodic Table)

Definition: The energy required to remove one mole of electrons from one mole of gaseous atoms to form one mole of gaseous 1+ ions. [2]
Mg vs Al: Magnesium has a stable $3s^2$ configuration. Aluminium has a $3s^2 3p^1$ configuration. The electron in the $3p$ orbital is higher in energy and further from the nucleus (more shielded), making it easier to remove. [2]
Na vs K: Potassium has a larger atomic radius. [1] Potassium has more occupied principal energy levels (n=4) compared to sodium (n=3), increasing the distance between the nucleus and valence electrons. [1]
F vs Cl: Fluorine has a smaller atomic radius. [1] The bonding pair of electrons is closer to the nucleus and less shielded, resulting in a stronger attraction for the shared pair of electrons. [1]
Trend: Generally increases across the period. [1] This is due to the increase in nuclear charge with a constant shielding effect, increasing the attraction between the nucleus and valence electrons. [1]
Atomic Radius: Nuclear charge increases across the period [1] while electrons are added to the same principal energy level (shielding remains relatively constant), pulling electrons closer to the nucleus. [1]
Na 2nd IE: The second electron is removed from a stable, full inner shell (2p⁶) [1] which is much closer to the nucleus and experiences significantly less shielding, requiring much more energy. [1]
Element: Aluminium (Al). [1]
Equation: $\text{SiO}_2(s) + 2\text{NaOH}(aq) \rightarrow \text{Na}_2\text{SiO}_3(aq) + \text{H}_2\text{O}(l)$ [2] (1 mark for correct formula/states, 1 mark for balancing).
NaCl vs MgCl₂: $\text{MgCl}_2$ has a higher melting point. [1] $\text{Mg}^{2+}$ has a higher charge density (smaller radius, higher charge) than $\text{Na}^+$ . [1] This results in stronger electrostatic attractions between the cation and the chloride anions in the giant ionic lattice. [1]
$\text{P}_4\text{O}_{10}$ : It is a strong Lewis acid. [1] The P-O bonds are highly polar, and the phosphorus atoms are electron-deficient, leading to a very exothermic reaction with water to form phosphoric acid. [1]
Sulfur Oxide: $\text{SO}_2$ (or $\text{SO}_3$ ). [1] Acidic. [1]
Nature Trend: Oxides change from basic ( $\text{Na}_2\text{O}, \text{MgO}$ ) to amphoteric ( $\text{Al}_2\text{O}_3$ ) to acidic ( $\text{SiO}_2, \text{P}_4\text{O}_{10}, \text{SO}_2, \text{Cl}_2\text{O}_7$ ). [2]
Amphoteric: It reacts with both acids (e.g., $\text{HCl}$ ) [1] and strong bases (e.g., $\text{NaOH}$ ) to form salts and water. [1]
Group 1 Reactivity: Increases down the group. [1] Atomic radius increases and shielding increases. [1] The attraction between the nucleus and the valence electron decreases, making it easier to lose the electron. [1]
He vs Ne: Neon has a larger molecular size/more electrons. [1] This leads to stronger London dispersion forces (Van der Waals forces) between neon atoms. [1]
(a) Formula: $\text{HX}$ (where X is halogen). [1] (b) HCl vs NaCl: $\text{HCl}$ is a simple covalent molecule with weak intermolecular forces. [1] $\text{NaCl}$ is a giant ionic lattice with strong electrostatic attractions between ions. [1]
F vs I: Fluorine is a stronger oxidizing agent. [1] Fluorine has a smaller atomic radius and higher electronegativity. [1] It has a greater tendency to attract and gain an electron to achieve a stable noble gas configuration. [1]
Al Structure: Giant metallic structure. [1] Consists of $\text{Al}^{3+}$ cations surrounded by a sea of delocalized valence electrons held by strong electrostatic forces. [1]
(a) Element: Aluminium (Al). [1] (b) Shape/Angle: Trigonal planar. [1] $120^\circ$ . [1]