AQA Year 11 Chemistry Quiz

Why do ionic compounds have high melting points?

• Because ions are small

• Because of weak intermolecular forces

• Because of strong electrostatic forces

• Because electrons move freely

Which substance is formed at the cathode during the electrolysis of molten lead bromide?

• Lead

• Bromine

• Oxygen

• Hydrogen

What is the purpose of cryolite in the electrolysis of aluminium oxide?

• Increase melting point

• Prevent oxygen formation

• Lower operating temperature

• Increase cost efficiency

What is the half equation for the formation of chlorine during electrolysis?

• Cl⁻ → Cl₂ + e⁻

• Cl₂ → 2Cl⁻

• 2Cl⁻ → Cl₂ + 2e⁻

• Cl → Cl₂ + 2e⁻

Why is graphite used as an electrode in electrolysis?

• It conducts electricity and is cheap

• It dissolves easily

• It is a metal

• It reacts with oxygen

Why do covalent substances like carbon dioxide not conduct electricity?

• They are acidic

• They are reactive

• They contain no ions

• They are solid

Which property is typical of a transition metal?

• Poor conductor

• High reactivity

• Low melting point

• Variable oxidation states

Why does magnesium lose two electrons when it reacts?

• To become heavier

• To form a neutral atom

• To achieve a full outer shell

• To create energy

Which element forms a white precipitate with sodium hydroxide solution?

• Iron(II)

• Aluminium

• Copper

• Iron(III)

A student makes 25g of product, but the theoretical yield is 40g. What is the percentage yield?

• 50%

• 62.5%

• 75%

• 88%