Reactivity Series, Extraction of Metals, Recycling and Metal Reactions

1. Metals W, X, Y and Z are tested with dilute hydrochloric acid.

metal	observation with dilute HCl
W	vigorous fizzing
X	slow fizzing
Y	no reaction
Z	moderate fizzing

Which order shows the metals from most reactive to least reactive?

A W, Z, X, Y
B Y, X, Z, W
C W, X, Z, Y
D Z, W, X, Y

2. A metal reacts slowly with cold water but rapidly with steam. It reacts with dilute acid to produce hydrogen.

Which metal could it be?

A sodium
B magnesium
C copper
D gold

3. Which metal reacts most vigorously with cold water?

A calcium
B magnesium
C zinc
D copper

4. Which statement about potassium, sodium and lithium is correct?

A Lithium reacts most violently with water because it is the smallest atom.
B Potassium reacts most violently with water because its outer electron is lost most easily.
C Sodium is least reactive because it has the lowest density.
D Potassium is least reactive because it has the most electron shells.

5. Which metal does not normally react with dilute hydrochloric acid to produce hydrogen?

A zinc
B magnesium
C iron
D copper

6. Which equation correctly represents magnesium reacting with hydrochloric acid?

A Mg + HCl → MgCl + H2
B Mg + 2HCl → MgCl2 + H2
C 2Mg + HCl → Mg2Cl + H2
D Mg + 2HCl → MgCl2 + 2H2

7. Which metal can displace copper from aqueous copper(II) sulfate?

A silver
B gold
C iron
D platinum

8. A strip of copper is placed in iron(II) sulfate solution.

What is observed?

A brown copper disappears and grey iron forms
B blue solution forms
C no reaction
D hydrogen gas is produced

9. Which pair of substances reacts to produce zinc metal?

A zinc oxide + carbon
B zinc + carbon dioxide
C zinc carbonate + oxygen
D zinc sulfate solution + copper

10. Which statement about displacement reactions is correct?

A A less reactive metal displaces a more reactive metal from its compound.
B A more reactive metal displaces a less reactive metal from its compound.
C A metal can displace itself only from molten compounds.
D Displacement reactions never involve electron transfer.

Written and Compiled By Sir Hunain Zia (AYLOTI), World Record Holder With 154 Total A Grades, 11 World Records and 7 Distinctions, Educate A Change.

11. Metal X displaces metal Y from Y(NO3)2 solution. Metal Z does not displace metal Y from Y(NO3)2 solution.

Which statement must be correct?

A X is more reactive than Y.
B Z is more reactive than Y.
C Y is more reactive than X.
D X is less reactive than Z.

12. A student adds zinc powder to copper(II) sulfate solution.

Which observation is expected?

A blue colour fades and a brown solid forms
B colourless solution turns blue
C green precipitate forms
D blue solution turns purple

13. Which ionic equation represents zinc reacting with copper(II) ions?

A Zn(s) + Cu2+(aq) → Zn2+(aq) + Cu(s)
B Zn2+(aq) + Cu(s) → Zn(s) + Cu2+(aq)
C Zn(s) + Cu(s) → ZnCu(s)
D Zn2+(aq) + Cu2+(aq) → Zn(s) + Cu(s)

14. In the reaction Zn + CuSO4 → ZnSO4 + Cu, which species is reduced?

A Zn
B Zn2+
C Cu2+
D SO4 2–

15. In the reaction Fe + CuSO4 → FeSO4 + Cu, what happens to iron?

A it gains electrons and is reduced
B it loses electrons and is oxidised
C it gains oxygen and is reduced
D it loses oxygen and is oxidised

16. Which metal is extracted from its ore by electrolysis rather than by reduction with carbon?

A iron
B zinc
C aluminium
D copper

17. Why is aluminium extracted by electrolysis?

A aluminium is below carbon in the reactivity series
B aluminium oxide is too stable to be reduced by carbon
C aluminium is found as the free metal
D aluminium oxide is a liquid at room temperature

18. Which metal oxide can be reduced by carbon?

A sodium oxide
B calcium oxide
C magnesium oxide
D zinc oxide

19. Which metal is extracted in a blast furnace?

A aluminium
B iron
C sodium
D potassium

20. Which raw material provides iron oxide in the blast furnace?

A limestone
B coke
C hematite
D cryolite

Written and Compiled By Sir Hunain Zia (AYLOTI), World Record Holder With 154 Total A Grades, 11 World Records and 7 Distinctions, Educate A Change.

21. What is the main purpose of coke in the blast furnace?

A to remove acidic impurities only
B to produce carbon monoxide, which reduces iron oxide
C to lower the melting point of aluminium oxide
D to form slag directly with iron

22. Which equation shows the main reduction of iron(III) oxide in the blast furnace?

A Fe2O3 + 3CO → 2Fe + 3CO2
B Fe2O3 + 3CO2 → 2Fe + 3CO
C Fe + CO2 → FeO + CO
D Fe2O3 + 3C → 2FeC + 3O

23. What is the role of limestone in the blast furnace?

A it reduces iron oxide to iron
B it decomposes to calcium oxide, which removes silicon dioxide impurities
C it burns to produce carbon monoxide
D it acts as a catalyst for iron formation

24. Which equation shows limestone decomposing in the blast furnace?

A CaCO3 → CaO + CO2
B CaO + SiO2 → CaSiO3
C C + O2 → CO2
D CO2 + C → 2CO

25. Which equation shows slag formation in the blast furnace?

A CaCO3 → CaO + CO2
B CaO + SiO2 → CaSiO3
C Fe2O3 + 3CO → 2Fe + 3CO2
D C + O2 → CO2

26. Which substance is removed as slag in the blast furnace?

A calcium silicate
B molten iron
C carbon monoxide
D aluminium oxide

27. In the blast furnace, carbon dioxide reacts with carbon to form carbon monoxide.

Which equation is correct?

A C + O2 → CO2
B CO2 + C → 2CO
C 2CO + O2 → 2CO2
D CO + C → CO2

28. Why is hot air blown into the blast furnace?

A to freeze molten iron quickly
B to burn coke and produce heat
C to remove oxygen from iron
D to dissolve limestone in water

29. Which product leaves from the bottom of the blast furnace?

A molten iron
B oxygen
C aluminium
D sulfuric acid

30. Which impurity in iron ore is removed by calcium oxide?

A silicon dioxide
B nitrogen
C sodium chloride
D water

Written and Compiled By Sir Hunain Zia (AYLOTI), World Record Holder With 154 Total A Grades, 11 World Records and 7 Distinctions, Educate A Change.

31. Aluminium is extracted from aluminium oxide dissolved in molten cryolite.

Why is cryolite used?

A to increase the melting point of aluminium oxide
B to lower the operating temperature and dissolve aluminium oxide
C to react with aluminium to make aluminium oxide
D to make oxygen form at the cathode

32. In aluminium extraction, which ions move to the cathode?

A Al3+
B O2–
C C4+
D Na+

33. Which half-equation occurs at the cathode during aluminium extraction?

A Al3+ + 3e– → Al
B Al → Al3+ + 3e–
C 2O2– → O2 + 4e–
D O2 + 4e– → 2O2–

34. Which half-equation occurs at the anode during aluminium extraction?

A Al3+ + 3e– → Al
B Al → Al3+ + 3e–
C 2O2– → O2 + 4e–
D O2 + 4e– → 2O2–

35. Why do graphite anodes in aluminium extraction need replacing?

A aluminium reacts with carbon to form aluminium carbide only
B oxygen produced reacts with carbon to form carbon dioxide
C cryolite reacts with carbon to form sodium
D molten aluminium dissolves all carbon instantly without reaction

36. Which statement about aluminium extraction is correct?

A aluminium forms at the anode
B oxygen forms at the cathode
C aluminium ions are reduced
D oxide ions gain electrons

37. Why is aluminium extraction expensive?

A aluminium oxide is not an ionic compound
B large amounts of electricity are needed
C the reaction occurs at room temperature only
D aluminium is extracted by heating with carbon

38. Why is iron not extracted by electrolysis in industry?

A iron is too unreactive to form compounds
B reduction with carbon is cheaper and works because iron is below carbon
C iron oxide does not contain ions
D iron is above aluminium in the reactivity series

39. Which metal can be extracted from its oxide by heating with carbon but not normally from its aqueous solution by displacement using copper?

A zinc
B sodium
C calcium
D aluminium

40. Which metal is found naturally as the element more often than aluminium?

A sodium
B potassium
C gold
D calcium

Written and Compiled By Sir Hunain Zia (AYLOTI), World Record Holder With 154 Total A Grades, 11 World Records and 7 Distinctions, Educate A Change.

41. Why is recycling aluminium especially useful?

A aluminium cannot be extracted from ores
B recycling uses much less energy than electrolysis
C aluminium becomes more reactive after recycling
D recycling removes the need for any transport

42. Which is an environmental benefit of recycling metals?

A it increases mining
B it reduces the need to extract ores
C it always produces more carbon dioxide than extraction
D it makes metals non-renewable

43. Which is an economic benefit of recycling iron?

A it saves raw materials and energy
B it makes iron ore disappear faster
C it prevents all rusting permanently
D it turns iron into aluminium

44. Which statement about recycling metals is correct?

A Recycling always produces a completely pure metal without sorting.
B Recycling can reduce landfill and conserve finite ore resources.
C Recycling requires no energy at all.
D Recycling is only possible for aluminium.

45. A metal carbonate is heated and forms a metal oxide and carbon dioxide.

Which carbonate is most likely to decompose easily on heating?

A sodium carbonate
B potassium carbonate
C copper(II) carbonate
D calcium carbonate

46. Which substance reacts with steam but not with cold water under normal O Level conditions?

A copper
B magnesium
C sodium
D gold

47. Which reaction produces hydrogen?

A copper + dilute hydrochloric acid
B zinc + dilute sulfuric acid
C silver + dilute hydrochloric acid
D gold + dilute sulfuric acid

48. A metal reacts with steam to form an oxide and hydrogen. The metal does not react with cold water.

Which equation could represent the reaction?

A Mg + H2O → MgO + H2
B 2Na + 2H2O → 2NaOH + H2
C Cu + H2O → CuO + H2
D Ag + H2O → AgOH + H2

49. A student has four metals: magnesium, zinc, copper and silver.

Which metal will react with the greatest number of the following solutions: ZnSO4, CuSO4, AgNO3?

A magnesium
B zinc
C copper
D silver

50. A metal X reacts with steam but not with cold water. X displaces copper from copper(II) sulfate but does not displace zinc from zinc sulfate.

Which metal is X most likely to be?

A magnesium
B iron
C sodium
D silver

Written and Compiled By Sir Hunain Zia (AYLOTI), World Record Holder With 154 Total A Grades, 11 World Records and 7 Distinctions, Educate A Change.

1. A

A right: Vigorous fizzing = fastest reaction = most reactive. Then moderate, then slow, then no reaction. Order: W, Z, X, Y.
B wrong: Puts unreactive Y first.
C wrong: X and Z are reversed.
D wrong: Z is less reactive than W.

2. B

A wrong: Sodium reacts vigorously with cold water, not slowly.
B right: Magnesium reacts very slowly with cold water but reacts more readily with steam; it also reacts with dilute acid to form hydrogen.
C wrong: Copper does not react with dilute acid or steam normally.
D wrong: Gold is very unreactive.

3. A

A right: Calcium reacts with cold water more vigorously than magnesium, zinc or copper.
B wrong: Magnesium reacts very slowly with cold water.
C wrong: Zinc does not react with cold water.
D wrong: Copper does not react with cold water.

4. B

A wrong: Lithium is least reactive of the three.
B right: Potassium has more shells, so its outer electron is lost most easily; it reacts most violently.
C wrong: Sodium is not least reactive here.
D wrong: More electron shells make potassium more reactive, not less.

5. D

A wrong: Zinc reacts with dilute hydrochloric acid.
B wrong: Magnesium reacts strongly with dilute hydrochloric acid.
C wrong: Iron reacts slowly with dilute hydrochloric acid.
D right: Copper is below hydrogen, so it does not normally produce hydrogen with dilute hydrochloric acid.

6. B

A wrong: Magnesium chloride formula is MgCl2, not MgCl.
B right: Mg + 2HCl → MgCl2 + H2.
C wrong: Formulae are incorrect.
D wrong: Hydrogen gas is H2, but coefficient should be 1, not 2.

7. C

A wrong: Silver is less reactive than copper.
B wrong: Gold is less reactive than copper.
C right: Iron is more reactive than copper, so it displaces copper from copper(II) sulfate.
D wrong: Platinum is less reactive than copper.

8. C

A wrong: Copper cannot displace iron.
B wrong: Blue solution would suggest copper(II) ions forming, but copper does not react here.
C right: Copper is less reactive than iron, so no displacement occurs.
D wrong: No acid is present to produce hydrogen.

9. A

A right: Carbon reduces zinc oxide to zinc.
B wrong: Zinc does not react with carbon dioxide to form zinc metal.
C wrong: Heating zinc carbonate gives zinc oxide and carbon dioxide, not zinc metal.
D wrong: Copper cannot displace zinc from zinc sulfate.

10. B

A wrong: Less reactive metals cannot displace more reactive metals.
B right: More reactive metals displace less reactive metals from their compounds.
C wrong: This is not a useful rule.
D wrong: Displacement reactions involve electron transfer/redox.

Written and Compiled By Sir Hunain Zia (AYLOTI), World Record Holder With 154 Total A Grades, 11 World Records and 7 Distinctions, Educate A Change.

11. A

A right: X displaces Y, so X is more reactive than Y.
B wrong: Z does not displace Y, so Z is less reactive than Y.
C wrong: Y is less reactive than X.
D wrong: X is more reactive than Y, and Z is less reactive than Y, so X is not less reactive than Z.

12. A

A right: Zinc displaces copper; blue CuSO4 fades and brown copper is deposited.
B wrong: Solution becomes less blue, not colourless to blue.
C wrong: No green precipitate forms.
D wrong: Purple is not expected.

13. A

A right: Zn loses electrons to form Zn2+; Cu2+ gains electrons to form Cu.
B wrong: Reverse reaction.
C wrong: Zinc and copper do not simply combine as ZnCu.
D wrong: Both metal ions are not reduced together.

14. C

A wrong: Zinc is oxidised.
B wrong: Zn2+ is the oxidised product.
C right: Cu2+ gains electrons to form copper, so it is reduced.
D wrong: Sulfate ions are spectators.

15. B

A wrong: Iron does not gain electrons.
B right: Iron loses electrons to form Fe2+, so it is oxidised.
C wrong: It does not gain oxygen here.
D wrong: It does not lose oxygen here.

16. C

A wrong: Iron is extracted by reduction with carbon monoxide/carbon in the blast furnace.
B wrong: Zinc can be extracted by reduction with carbon.
C right: Aluminium is too reactive and is extracted by electrolysis.
D wrong: Copper can be extracted by reduction or other methods, not mainly electrolysis from oxide at this level.

17. B

A wrong: Aluminium is above carbon, not below it.
B right: Aluminium oxide is very stable and cannot be reduced by carbon economically.
C wrong: Aluminium is found in compounds, not usually free.
D wrong: Aluminium oxide is solid at room temperature.

18. D

A wrong: Sodium is too reactive; sodium oxide cannot be reduced by carbon.
B wrong: Calcium oxide cannot be reduced by carbon at O Level.
C wrong: Magnesium oxide cannot be reduced by carbon.
D right: Zinc oxide can be reduced by carbon.

19. B

A wrong: Aluminium is extracted by electrolysis.
B right: Iron is extracted in a blast furnace.
C wrong: Sodium is extracted by electrolysis.
D wrong: Potassium is too reactive and not extracted in a blast furnace.

20. C

A wrong: Limestone removes impurities.
B wrong: Coke provides carbon/carbon monoxide and heat.
C right: Hematite contains iron(III) oxide.
D wrong: Cryolite is used in aluminium extraction.

Written and Compiled By Sir Hunain Zia (AYLOTI), World Record Holder With 154 Total A Grades, 11 World Records and 7 Distinctions, Educate A Change.

21. B

A wrong: Limestone/calcium oxide removes acidic impurities.
B right: Coke burns to provide heat and forms carbon monoxide, which reduces iron oxide.
C wrong: Cryolite is used in aluminium extraction.
D wrong: Slag forms from calcium oxide and silicon dioxide, not directly from coke and iron.

22. A

A right: Fe2O3 + 3CO → 2Fe + 3CO2 is the main reduction.
B wrong: Carbon dioxide is not reducing iron oxide.
C wrong: This is not the blast furnace reduction.
D wrong: FeC is not the product.

23. B

A wrong: Carbon monoxide reduces iron oxide.
B right: Limestone decomposes to calcium oxide, which reacts with silicon dioxide impurities.
C wrong: Coke burns to produce heat/carbon monoxide.
D wrong: Limestone is not a catalyst.

24. A

A right: CaCO3 → CaO + CO2.
B wrong: This is slag formation.
C wrong: This is coke combustion.
D wrong: This forms carbon monoxide.

25. B

A wrong: This is limestone decomposition.
B right: CaO + SiO2 → CaSiO3, calcium silicate slag.
C wrong: This is iron oxide reduction.
D wrong: This is combustion.

26. A

A right: Calcium silicate is slag.
B wrong: Molten iron is the desired product.
C wrong: Carbon monoxide is a reducing gas.
D wrong: Aluminium oxide is not the slag in the blast furnace.

27. B

A wrong: This forms carbon dioxide from carbon.
B right: CO2 + C → 2CO.
C wrong: This converts carbon monoxide to carbon dioxide.
D wrong: Not balanced/correct for blast furnace.

28. B

A wrong: The furnace must stay hot, not freeze iron.
B right: Hot air allows coke to burn, producing heat.
C wrong: Carbon monoxide removes oxygen from iron oxide.
D wrong: Limestone is not dissolved in water.

29. A

A right: Molten iron collects at the bottom and is tapped off.
B wrong: Oxygen is not the bottom product.
C wrong: Aluminium is not produced.
D wrong: Sulfuric acid is unrelated.

30. A

A right: Silicon dioxide is an acidic impurity removed by calcium oxide.
B wrong: Nitrogen is not the main impurity removed this way.
C wrong: Sodium chloride is not the key impurity.
D wrong: Water is not removed as slag.

Written and Compiled By Sir Hunain Zia (AYLOTI), World Record Holder With 154 Total A Grades, 11 World Records and 7 Distinctions, Educate A Change.

31. B

A wrong: Cryolite lowers the melting point.
B right: Cryolite dissolves aluminium oxide and lowers the operating temperature.
C wrong: Cryolite does not react with aluminium to form aluminium oxide.
D wrong: Oxygen forms at the anode, not cathode.

32. A

A right: Al3+ ions move to the negative cathode.
B wrong: O2– ions move to the positive anode.
C wrong: C4+ is not the relevant ion.
D wrong: Sodium ions from cryolite are not discharged as the intended product.

33. A

A right: Aluminium ions gain electrons at the cathode: Al3+ + 3e– → Al.
B wrong: This is oxidation of aluminium, not extraction at cathode.
C wrong: This is the anode reaction.
D wrong: This is reduction of oxygen, not the cathode reaction here.

34. C

A wrong: This occurs at the cathode.
B wrong: Aluminium metal is not oxidised at the anode here.
C right: Oxide ions lose electrons at the anode: 2O2– → O2 + 4e–.
D wrong: This is reduction, not oxidation.

35. B

A wrong: Aluminium carbide is not the main reason.
B right: Oxygen formed at the anode reacts with carbon graphite to form carbon dioxide, so anodes wear away.
C wrong: Cryolite does not form sodium this way.
D wrong: Carbon is consumed by reaction, not just dissolved.

36. C

A wrong: Aluminium forms at the cathode.
B wrong: Oxygen forms at the anode.
C right: Aluminium ions gain electrons, so they are reduced.
D wrong: Oxide ions lose electrons.

37. B

A wrong: Aluminium oxide is ionic.
B right: Electrolysis needs large amounts of electricity, making extraction expensive.
C wrong: It does not occur at room temperature.
D wrong: Aluminium is not extracted by heating with carbon.

38. B

A wrong: Iron forms compounds.
B right: Iron is below carbon, so carbon/carbon monoxide reduction is cheaper than electrolysis.
C wrong: Iron oxide contains ions.
D wrong: Iron is below aluminium, not above it in reactivity.

39. A

A right: Zinc oxide can be reduced by carbon, but copper cannot displace zinc from zinc ions in solution.
B wrong: Sodium cannot be extracted by carbon.
C wrong: Calcium cannot be extracted by carbon.
D wrong: Aluminium cannot be extracted by carbon.

40. C

A wrong: Sodium is very reactive and found in compounds.
B wrong: Potassium is very reactive and found in compounds.
C right: Gold is very unreactive and can be found native as the element.
D wrong: Calcium is reactive and found in compounds.

Written and Compiled By Sir Hunain Zia (AYLOTI), World Record Holder With 154 Total A Grades, 11 World Records and 7 Distinctions, Educate A Change.

41. B

A wrong: Aluminium can be extracted from ores, but extraction is energy-intensive.
B right: Recycling aluminium uses far less energy than extracting it by electrolysis.
C wrong: Recycling does not make aluminium more reactive.
D wrong: Transport is still needed.

42. B

A wrong: Recycling reduces the need for mining.
B right: Recycling reduces the need to extract ores.
C wrong: Recycling usually reduces carbon dioxide emissions compared with extraction.
D wrong: Metals are finite resources; recycling conserves them.

43. A

A right: Recycling iron saves raw materials and energy.
B wrong: It helps conserve iron ore.
C wrong: It does not permanently prevent rusting.
D wrong: It does not turn iron into aluminium.

44. B

A wrong: Sorting and purification may still be needed.
B right: Recycling reduces landfill and conserves finite ore resources.
C wrong: Recycling still requires energy.
D wrong: Many metals can be recycled.

45. C

A wrong: Sodium carbonate is thermally stable at O Level.
B wrong: Potassium carbonate is thermally stable at O Level.
C right: Copper(II) carbonate decomposes easily on heating to copper(II) oxide and carbon dioxide.
D wrong: Calcium carbonate decomposes on strong heating, but copper(II) carbonate decomposes more easily.

46. B

A wrong: Copper does not react with steam.
B right: Magnesium reacts with steam but not significantly with cold water under normal O Level conditions.
C wrong: Sodium reacts vigorously with cold water.
D wrong: Gold does not react with steam.

47. B

A wrong: Copper does not react with dilute hydrochloric acid.
B right: Zinc reacts with dilute sulfuric acid to produce hydrogen.
C wrong: Silver does not react with dilute hydrochloric acid.
D wrong: Gold does not react with dilute sulfuric acid.

48. A

A right: Magnesium reacts with steam: Mg + H2O → MgO + H2.
B wrong: Sodium reacts with cold water to form sodium hydroxide, not steam-only oxide reaction.
C wrong: Copper does not react with steam under these conditions.
D wrong: Silver does not react like this.

49. A

A right: Magnesium is more reactive than zinc, copper and silver, so it reacts with ZnSO4, CuSO4 and AgNO3.
B wrong: Zinc reacts with CuSO4 and AgNO3, but not ZnSO4.
C wrong: Copper reacts with AgNO3 only.
D wrong: Silver reacts with none of these.

50. B

A wrong: Magnesium would displace zinc from zinc sulfate because it is more reactive than zinc.
B right: Iron reacts with steam, displaces copper, but does not displace zinc.
C wrong: Sodium reacts with cold water and would be too reactive.
D wrong: Silver does not displace copper and does not react with steam.

Written and Compiled By Sir Hunain Zia (AYLOTI), World Record Holder With 154 Total A Grades, 11 World Records and 7 Distinctions, Educate A Change.