Metals below carbon in the reactivity series
5 marks · HardThe table shows the position of three metals in the reactivity series:
| Metal | Position relative to carbon |
|---|---|
| Lead | Below carbon |
| Aluminium | Above carbon |
| Zinc | Below carbon |
A manufacturer wants to extract each metal from its oxide using the cheapest method.
State which two of these metals can be extracted from their oxides by heating with carbon. Explain your answer using the reactivity series.
Aluminium oxide is not extracted by heating with carbon. Explain why not, and name the method used instead.
Write a balanced symbol equation for the extraction of zinc from zinc oxide using carbon.
Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.
Show answer
(a) Lead and zinc can be extracted by heating with carbon because both are below carbon in the reactivity series. Carbon is more reactive and can remove oxygen from their oxides.
(b) Aluminium oxide cannot be reduced by carbon because aluminium is above carbon in the reactivity series. Aluminium is too reactive. Instead, aluminium is extracted by electrolysis of its molten oxide.
(c) ZnO(s) + C(s) -> Zn(s) + CO(g) · must show Balanced equation with states.
Show mark scheme and worked solution
Marking points
B1 (a) · 1 mark · Identifies both lead and zinc as the metals that can be extracted by heating with carbon.
B2 (a) · 1 mark · Explanation: Both are below carbon in the reactivity series, so carbon can reduce their oxides.
B3 (b) · 1 mark · Explains that aluminium is above carbon in the reactivity series / too reactive for carbon reduction.
B4 (b) · 1 mark · Names electrolysis as the method for extraction of aluminium oxide.
B5 (c) · 1 mark · Writes correct balanced symbol equation: ZnO(s) + C(s) -> Zn(s) + CO(g)
Worked solution
a) Lead and zinc can be extracted from their oxides by heating with carbon. Carbon is more reactive than both and so can remove oxygen from their oxides (carbon is above them in the reactivity series).
b) Aluminium cannot be extracted by heating with carbon because it is more reactive than carbon. Carbon cannot reduce aluminium oxide. Instead, electrolysis is used to extract aluminium from its oxide.