Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Section
Why things conduct electricity
17 practice questions
Practice questions
11–17 of 17
Question 11
4 marks · Normal
Answer and see the solution →(a)[2 marks]The table shows the results from testing four substances for electrical conductivity:
Substance State Conducts electricity? Potassium bromide Solid No Potassium bromide Molten Yes Glucose Solution in water No Potassium bromide Solution in water Yes Use the data to identify the substance(s) that conduct electricity and describe the conditions in which conduction occurs.
(b)[2 marks]Suggest a reason why potassium bromide conducts electricity in its molten state and in aqueous solution, but not as a solid.
Question 12
1 mark · Normal
Answer and check →Which statement best explains why sodium chloride solution conducts electricity?
- A.It contains ions that are free to move.
- B.It contains free electrons that carry charge.
- C.It contains molecules that can move around.
- D.It contains atoms that are free to move.
Question 13
4 marks · Normal
Answer and see the solution →(a)[2 marks]Explain why molten zinc chloride can conduct electricity but solid zinc chloride cannot.
(b)[2 marks]Describe what must be present in a substance for it to conduct electricity.
Question 14
2 marks · Normal
Answer and see the solution →Explain why solid sodium chloride does not conduct electricity, but molten sodium chloride does.
Question 15
2 marks · Hard
Answer and see the solution →Explain why pure, solid silver chloride does not conduct electricity, but when dissolved in water, it does.
Question 16
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 17
2 marks · Hard
Answer and see the solution →Explain, with reference to structure and particles, why molten lead(II) bromide can conduct electricity.