Question Bank — Metals and Non-metals

Section A — MCQs (10 questions, 1 mark each)

1. Which of the following metals is stored in kerosene oil to prevent its reaction with air and moisture?
(a) Magnesium (b) Sodium (c) Copper (d) Zinc

2. An element X forms an oxide that reacts with both acids and bases to form salt and water. X is most likely:
(a) Sodium (b) Aluminium (c) Sulphur (d) Iron

3. Assertion (A): Copper vessels get coated with a green layer when exposed to moist air for a long time.
Reason (R): Copper reacts with moist carbon dioxide to form basic copper carbonate.
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true but R is not the correct explanation of A.
(c) A is true but R is false.
(d) A is false but R is true.

4. Which of the following non-metals exists in liquid state at room temperature?
(a) Carbon (b) Sulphur (c) Bromine (d) Iodine

5. Assertion (A): Ionic compounds conduct electricity in the molten state but not in the solid state.
Reason (R): In the solid state, ions are held by strong electrostatic forces and cannot move freely.
(a) Both A and R are true and R is the correct explanation of A.
(b) Both A and R are true but R is not the correct explanation of A.
(c) A is true but R is false.
(d) A is false but R is true.

6. Metals can be drawn into wires. This property is called:
(a) Malleability (b) Ductility (c) Sonority (d) Lustre

7. Which of the following metals will displace copper from copper sulphate solution?
(a) Silver (b) Gold (c) Iron (d) Mercury

8. The process of heating sulphide ores strongly in excess air to convert them into oxides is known as:
(a) Calcination (b) Roasting (c) Reduction (d) Refining

9. Which metal is found in native state in nature?
(a) Sodium (b) Aluminium (c) Gold (d) Zinc

10. Graphite, an allotrope of carbon, conducts electricity while diamond does not. This is because:
(a) Graphite has free electrons while diamond does not.
(b) Diamond is harder than graphite.
(c) Graphite is a metal and diamond is a non-metal.
(d) Diamond has higher melting point.

Section B — Very Short Answer (6 questions, 2 marks each)

11. Why are electric wires coated with PVC or rubber?
12. Name two metals that are highly malleable and ductile. Give one use of each based on these properties.
13. What happens when magnesium ribbon is burnt in air? Write the balanced chemical equation.
14. Why is gold used for making jewellery while sodium is stored under oil?
15. Define gangue. How is it different from an ore?
16. Write the balanced chemical equation for the reaction of zinc with dilute hydrochloric acid.

Section C — Short Answer (5 questions, 3 marks each)

17. Explain with reason why (i) aluminium oxide is called an amphoteric oxide, (ii) sodium is kept immersed in kerosene, (iii) copper is a better conductor of heat than lead.
18. Describe an activity to show that metals are good conductors of electricity. Draw a labelled diagram of the setup.
19. Differentiate between roasting and calcination with one example each. Why are sulphide and carbonate ores converted to oxides before reduction?
20. What are the conditions necessary for rusting of iron? How can rusting be prevented by galvanisation?
21. A metal M reacts with dilute HCl to liberate hydrogen gas and forms a salt. Another metal N does not react with dilute HCl but displaces M from its salt solution. Arrange M and N in the reactivity series and justify.

Section D — Long Answer (3 questions, 5 marks each)

22. (a) Draw a neat labelled diagram of the electrolytic refining of copper. Mark the anode, cathode, electrolyte and direction of flow of electrons. (b) Explain the process with balanced equations showing how pure copper is obtained. (Diagram-based)
23. Describe the extraction of metals of medium reactivity (such as zinc or iron) from their ores. Explain the steps of roasting/calcination and reduction with carbon with balanced equations. Why is electrolytic reduction used for metals high in the reactivity series?
24. What are ionic compounds? List any four general properties of ionic compounds with explanation. How do these properties arise from their structure?

Section E — Case/Source-Based (2 questions, 4 marks each)

25. Case: An iron nail is placed in three test tubes. Test tube A contains water and is corked. Test tube B contains boiled distilled water with a layer of oil and is corked. Test tube C contains anhydrous calcium chloride and is corked. After a few days, rusting is observed only in test tube A.
(i) What does this experiment show about the conditions required for rusting? (1)
(ii) Name the brown flaky substance formed on iron. (1)
(iii) Suggest one method (other than painting) to prevent rusting of an iron gate used outdoors. (1)
(iv) Why does the oil layer in test tube B prevent rusting? (1)

26. Case: A student heats a clean aluminium wire clamped on a stand. A pin is attached to the free end with wax. After some time the wax melts and the pin falls. The student concludes that aluminium is a good conductor of heat.
(i) Name the property demonstrated by the metal. (1)
(ii) Which two metals are the best conductors of heat according to the chapter? (1)
(iii) Why do cooking vessels are usually made of aluminium or copper? (1)
(iv) Name one metal that is a poor conductor of heat. (1)

Section F — HOTS and Application (4 questions, 3 marks each)

27. Predict-and-justify: What would happen if a piece of sodium metal is kept exposed to air instead of being stored in kerosene? Explain with reason.
28. Analyse anomalous observation: In an experiment, a student observes that iodine (a non-metal) has a shiny surface like metals, yet it does not conduct electricity. How can this observation be explained using chapter concepts?
29. Apply to unfamiliar situation: A farmer notices that the iron fencing around his field is rusting rapidly near a coastal area but slowly inland. Apply the concept of corrosion to explain the difference and suggest a suitable prevention method.
30. Compare two situations: Two test tubes contain iron nails. One nail is wrapped with copper wire and placed in copper sulphate solution; the other is placed alone in the same solution. In which case will a reaction occur? Justify which situation shows displacement and why the outcomes differ.