Metallurgy and Extraction of Metals - Question Bank

1. The Dow process is used for the extraction of which metal from seawater?
A) Sodium
B) Magnesium
C) Potassium
D) Calcium
2. Which term describes the process of removing a metal from its ore in an aqueous solution?
A) Pyrometallurgy
B) Electrometallurgy
C) Hydrometallurgy
D) Thermomettalurgy
3. Which of the following is an example of a pyrometallurgical process?
A) Electrolytic refining
B) Leaching with cyanide
C) Smelting in a blast furnace
D) Zone refining
4. What is the main purpose of using carbon monoxide as a reducing agent in the blast furnace?
A) It is readily available and cost-effective
B) It is a stronger reducing agent than carbon at high temperatures
C) It reacts with impurities to form slag
D) It helps to melt the iron ore
5. Which method is employed for the extraction of tin from stannic oxide (SnO₂)?
A) Electrolysis
B) Smelting with carbon
C) Reduction with hydrogen
D) Leaching
6. The Bessemer process, though primarily for steel making, involves the removal of impurities from molten pig iron. Which of the following is NOT typically removed in a Bessemer converter?
A) Carbon
B) Silicon
C) Manganese
D) Phosphorus
7. The extraction of zinc from zinc blende (ZnS) typically involves roasting followed by:
A) Electrolytic reduction
B) Smelting with carbon
C) Reduction with aluminium
D) Leaching with cyanide
8. Which of the following metals is extracted by electrolysis of its fused salt?
A) Iron
B) Copper
C) Sodium
D) Silver
9. What is the primary use of the thermite reaction in metallurgy?
A) Purification of metals
B) Extraction of highly reactive metals
C) Welding of broken iron parts, like railway tracks
D) Concentration of ores
10. Thermite reaction is an example of:
A) Electrolytic reduction
B) Reduction by carbon
C) Displacement method using a more reactive metal
D) Reduction using hydrogen
11. Which of the following processes is used to convert a metal oxide into a metal by heating it with a more electropositive metal?
A) Smelting
B) Reduction
C) Displacement method
D) Electrolysis
12. Smelting is a process of extraction that typically involves:
A) Heating in the absence of air
B) Electrolysis of molten salts
C) Heating with a reducing agent and a flux above the melting point
D) Dissolving the ore in a solvent
13. Which of the following is a reducing agent commonly used in smelting at high temperatures?
A) Carbon monoxide
B) Hydrogen
C) Aluminium
D) All of the above
14. The term 'gangue' refers to:
A) The desired metal in the ore
B) The valuable mineral extracted from the ore
C) The undesired rocky material associated with the ore
D) The flux used in smelting
15. Which of the following ores can be separated by magnetic separation?
A) Copper pyrites
B) Haematite
C) Bauxite
D) Zinc blende
16. What is the basic principle behind the magnetic separation of ores?
A) Difference in density
B) Difference in magnetic properties
C) Difference in wettability
D) Difference in chemical reactivity
17. In the Van Arkel method, a metal reacts with iodine to form a volatile metal iodide. This iodide is then heated to decompose it into the pure metal and iodine. Which metal is commonly purified by this method?
A) Copper
B) Iron
C) Titanium
D) Zinc
18. The Van Arkel method is used for the purification of which group of metals?
A) Alkali metals
B) Alkaline earth metals
C) Highly electropositive metals like Zr, Ti, Hf
D) Transition metals
19. In Mond's process, nickel reacts with carbon monoxide to form nickel carbonyl. What is the state of nickel carbonyl at room temperature?
A) Solid
B) Liquid
C) Gas
D) Aqueous solution
20. Mond's process is used for the purification of which metal?
A) Iron
B) Nickel
C) Copper
D) Gold
21. What is the term for the process where a metal is purified by converting it into a volatile compound and then decomposing it?
A) Smelting
B) Mond's process
C) Pyrometallurgy
D) Hydrometallurgy
22. Which of the following metals is typically extracted by electrolysis of its molten chloride?
A) Copper
B) Iron
C) Magnesium
D) Silver
23. In the Parkes process, molten lead is treated with molten zinc. What happens to the impurity being removed?
A) It dissolves in lead
B) It forms an alloy with zinc and rises to the surface
C) It reacts with zinc to form a gas
D) It settles at the bottom of the molten lead
24. The Parkes process is used for the removal of which impurity from lead?
A) Copper
B) Silver
C) Iron
D) Zinc
25. Which metal is extracted using the Parkes process?
A) Iron
B) Copper
C) Lead
D) Zinc
26. The process of separating a metal from its ore by dissolving it in a suitable solvent is called:
A) Smelting
B) Roasting
C) Leaching
D) Calcination
27. What is the material used for electrodes in the electrolytic cell for Aluminium extraction?
A) Iron
B) Copper
C) Graphite (carbon)
D) Platinum
28. What is the role of cryolite (Na₃AlF₆) in the electrolytic extraction of Aluminium?
A) It acts as a reducing agent
B) It increases the melting point of alumina
C) It decreases the melting point of alumina and increases its conductivity
D) It is the source of aluminium
29. The extraction of Aluminium from bauxite is done by the:
A) Smelting process
B) Electrolytic reduction of molten alumina (Al₂O₃) dissolved in cryolite
C) Reduction with carbon
D) Acid leaching process
30. What is the primary ore of Aluminium?
A) Haematite
B) Bauxite
C) Magnetite
D) Copper pyrites
31. Which of the following metals can be extracted by leaching with a dilute cyanide solution followed by displacement with zinc?
A) Iron
B) Copper
C) Gold
D) Aluminium
32. Thermodynamic principles, like Ellingham diagrams, are useful in predicting:
A) The rate of a reduction reaction
B) The feasibility of a reduction reaction at a given temperature
C) The purity of the extracted metal
D) The physical properties of the ore
33. The extraction of metals from their ores using a reducing agent is known as:
A) Smelting
B) Calcination
C) Reduction
D) Roasting
34. Which method is used for the purification of metals like silicon and germanium, which have very low impurity levels?
A) Electrolytic refining
B) Smelting
C) Zone refining
D) Distillation
35. What is the 'anode mud' formed during the electrolytic refining of copper?
A) Impure copper particles
B) Valuable metals like gold, silver, and platinum
C) Oxidized impurities
D) Electrolyte residue
36. In electrolytic refining of copper, the impure copper is made the anode, and a thin strip of pure copper is made the cathode. What is used as the electrolyte?
A) Dilute sulphuric acid
B) Molten copper chloride
C) Acidified copper sulphate solution
D) Copper oxide solution
37. What is the term for the process of removing impurities from an impure metal by electrolysis?
A) Smelting
B) Calcination
C) Electrolytic refining
D) Zone refining
38. The slag formed during the smelting of iron from haematite is primarily:
A) Iron sulphide
B) Calcium silicate
C) Aluminium oxide
D) Ferrous oxide
39. Which of the following is a common flux used in the smelting of iron ore?
A) Silica (SiO₂)
B) Limestone (CaCO₃)
C) Coke (C)
D) Alumina (Al₂O₃)
40. In the blast furnace, iron is extracted from haematite (Fe₂O₃). What acts as the reducing agent in the lower, hotter part of the furnace?
A) Carbon monoxide (CO)
B) Carbon (C)
C) Calcium carbonate (CaCO₃)
D) Silicon dioxide (SiO₂)
41. What is the main purpose of adding a flux during smelting?
A) To increase the melting point of the ore
B) To reduce the ore to the metal
C) To remove impurities by forming a fusible slag
D) To increase the temperature of the furnace
42. During roasting of sulphide ores, the sulphide is converted into:
A) Sulphate
B) Sulphide
C) Oxide
D) Sulphur
43. Roasting is typically carried out for which type of ores?
A) Carbonates
B) Sulphides
C) Oxides
D) Chlorides
44. Which process involves heating the concentrated ore in the absence or limited supply of air below its melting point?
A) Smelting
B) Calcination
C) Roasting
D) Reduction
45. In the froth flotation process, the mineral particles attach to the air bubbles and rise to the surface, while the undesired impurities (gangue) sink. What substance is typically used to make the mineral particles hydrophobic?
A) Depressant
B) Frother
C) Collector
D) Activator
46. Which of the following is NOT a common method for concentrating ores?
A) Hydraulic washing
B) Froth flotation
C) Magnetic separation
D) Electrolytic refining
47. What is the term for the naturally occurring solid material from which a metal can be profitably extracted?
A) Mineral
B) Ore
C) Gangue
D) Slag
48. Which method is commonly used to extract highly reactive metals like Sodium and Potassium?
A) Electrolysis of molten salts
B) Smelting with carbon
C) Reduction with hydrogen
D) Leaching with cyanide
49. What is the primary objective of metallurgy?
A) To study the properties of metals
B) To extract metals from their ores and prepare them for use
C) To synthesize new metallic alloys
D) To understand the atomic structure of metals
50. Which of the following terms describes the process of separating a metal from its ore?
A) Refining
B) Smelting
C) Extraction
D) Roasting