Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Unit
Principles of Chemistry
991 practice questions
Topics covered
- States of Matter102 practice questions
- Elements, Compounds and Mixtures69 practice questions
- Atomic Structure108 practice questions
- The Periodic Table103 practice questions
- Chemical Formulae, Equations and Calculations Part 119 practice questions
- Chemical Formulae, Equations and Calculations Part 2144 practice questions
- Ionic Bonding143 practice questions
- Covalent Bonding68 practice questions
- Metallic Bonding19 practice questions
- Electrolysis198 practice questions
Practice questions
791–800 of 991
Question 791
5 marks · Hard
Answer and see the solution →A teacher tests the electrical conductivity of four substances in different states. The results are shown in the table below.
Conductivity of substances in different states Substance State Conducts electricity? Potassium nitrate Solid No Potassium nitrate Aqueous Yes Sulfur dioxide Liquid No Lead(II) bromide Molten Yes (a)[1 mark]Identify which of the substances in the table are ionic compounds.
(b)[2 marks]Explain why potassium nitrate conducts electricity when dissolved in water but not as a solid.
(c)[2 marks]Suggest why sulfur dioxide does not conduct electricity, even when liquid. Use your knowledge of bonding.
Question 792
2 marks · Hard
Answer and see the solution →Explain, with reference to structure and particles, why molten lead(II) bromide can conduct electricity.
Question 793
1 mark · Easy
Answer and see the solution →State the name of the liquid or solution that undergoes electrolysis and contains ions.
Question 794
3 marks · Easy
Answer and see the solution →The diagram shows an apparatus for electrolysis.
(a)[1 mark]Name the positively charged electrode.
(b)[1 mark]Name the negatively charged electrode.
(c)[1 mark]Give the term for the solution or molten compound that contains ions in this process.
Question 795
2 marks · Easy
Answer and see the solution →How many positive ions and how many negative ions are present in the formula unit of magnesium bromide ()? State the name for each type of ion.
Question 796
2 marks · Easy
Answer and see the solution →Describe how you could investigate whether molten lead(II) bromide conducts electricity. Explain the observation that would show conduction is occurring.
Question 797
3 marks · Easy
Answer and see the solution →The table shows the roles of electrodes and ions in electrolysis of sodium bromide solution.
(a)[0 marks]Part Type Charge Electrode A Electrode B Na^+ ion Br^- ion (b)[3 marks]Complete the table by naming the type (anode/cathode/cation/anion) and the charge (+/–) for each part.
Question 798
1 mark · Easy
Answer and see the solution →State the name given to a negatively charged ion formed when an atom gains electrons.
Question 799
3 marks · Easy
Answer and see the solution →Describe an experiment to investigate the electrolysis of aqueous copper(II) sulfate solution using copper electrodes.
(a)[1 mark]Name the apparatus needed for this investigation.
(b)[1 mark]State what you would observe at the electrodes during electrolysis.
(c)[1 mark]Explain briefly why a change occurs at the anode.
Question 800
2 marks · Easy
Answer and see the solution →The formula of calcium chloride is . Explain which ions are present and give their names and charges.