Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Section
Metals above carbon in the reactivity series
18 practice questions
Practice questions
1–8 of 8 · Normal
Question 1
2 marks · Normal
Answer and see the solution →State why metals above carbon in the reactivity series cannot be extracted from their oxides by reduction with carbon.
Question 2
4 marks · Normal
Answer and see the solution →Aluminium is extracted from aluminium oxide using electrolysis.
(a)[1 mark]Name the substance in which aluminium oxide is dissolved for the electrolysis process.
(b)[1 mark]Write the ionic equation for the reaction at the cathode during the electrolysis of aluminium oxide.
(c)[1 mark]Write the ionic equation for the reaction at the anode during this process.
(d)[1 mark]Explain why the extraction of aluminium by electrolysis is much more expensive than extracting iron by reduction with carbon.
Question 3
3 marks · Normal
Answer and see the solution →Titanium cannot be extracted from its oxide using carbon. It is often extracted by heating titanium oxide with sodium or magnesium.
Explain why this method is expensive and give a reason why this process is used instead of reduction with carbon.
Question 4
4 marks · Normal
Answer and see the solution →The table shows some metals and whether they can be extracted from their oxides by using carbon.
(a)[0 marks]Extraction of Metals by Carbon Metal Extracted using carbon (Yes/No) Potassium No Iron Yes Aluminium No Copper Yes (b)[1 mark]Identify two metals from the table that cannot be extracted using carbon.
(c)[1 mark]Explain why potassium cannot be extracted by reduction with carbon.
(d)[1 mark]State the method used to extract aluminium from its ore.
(e)[1 mark]Describe why copper can be extracted by using carbon.
Question 5
1 mark · Normal
Answer and check →Which statement describes a correct feature of aluminium extraction by electrolysis?
- A.The process uses less electricity than iron extraction.
- B.Aluminium oxide is dissolved in molten cryolite.
- C.Aluminium forms at the anode as a gas.
- D.The anode reaction is Al^3+ + 3e^- -> Al.
Question 6
2 marks · Normal
Answer and see the solution →Give one reason why electrolysis is used to extract aluminium, but iron is extracted by reduction with carbon.
Question 7
4 marks · Normal
Answer and see the solution →Scandium is a metal above carbon in the reactivity series. It can be extracted from its oxide by heating with calcium. Use your knowledge of the reactivity series to answer the questions.
(a)[2 marks]Explain why calcium can be used to extract scandium from its oxide.
(b)[2 marks]Suggest one reason, other than expense, why this method might not be widely used for large-scale scandium extraction.
Question 8
3 marks · Normal
Answer and see the solution →Aluminium is extracted by electrolysis, while iron is extracted by reduction with carbon. The extraction of 1 tonne of aluminium requires 14,000 kWh of electricity at a cost of £0.12 per kWh. The extraction of 1 tonne of iron requires 500 kWh of electricity at the same cost per kWh. Calculate the difference in electricity cost between extracting 1 tonne of aluminium and 1 tonne of iron, and explain one reason why aluminium is extracted by electrolysis rather than by carbon reduction.
(a)[2 marks]Calculate the electricity cost to extract 1 tonne of aluminium and 1 tonne of iron.
(b)[1 mark]Explain one reason why aluminium is extracted using electrolysis rather than by reduction with carbon.