Chapter 8 : METALS

Choose Appropriate Alternative

1. What is the chemical formula of alumina?
   

   [A] Al2O3 [B] Al2O3.2H2O [C] Al2O3.H2O [D] NaAlO2

2. Which of the following reactions is called roasting?
   

   [A] ZnCO3(s) --> ZnO(s) + CO2(g) [B] 2ZnS(s) + 3O2(g) --> 2ZnO(s) + 2SO2(g) 
   [C] ZnO(s) + C(s) --> Zn(s) + CO(g) [D] Zn(s) + H2O(g) --> ZnO(s) + H2(g)

3. Which of the following is an alloy?
   

   [A] Silver [B] Gallium [C] 22 Carat gold [D] 24 Carat gold

4. During which of the following reactions is dihydrogen gas not produced under normal conditions?
   

   [A] Metal + dilute sulphuric acid [B] Metal + dilute hydrochloric acid 
   [C] Metal + dilute nitric acid    [D] Metal + water

5. In which of the following, is displacement reaction possible?
   

   [A] Solution of NaCl + coin of copper  [B] Solution of MgCl2 + coin of aluminium
   [C] Solution of FeSO4 + coin of silver [D] Solution of AgNO3 + coin of copper

6. Which of the following reactions is not possible?
   

   [A] Zn(s) + CuSO4(aq) --> ZnSO4(aq) + Cu(s) [B] Zn(s) + FeSO4(aq) --> ZnSO4(aq) + Fe(s)
   [C] Fe(s) + CuSO4(aq) --> FeSO4(aq) + Cu(s) [D] Cu(s) + FeSO4(aq) --> CuSO4(aq) + Fe(s)

7. By which reaction is a metal obtained from its oxide?
   

   [A] Liquefaction [B] Reduction [C] Calcination [D] Roasting

8. Which of the following statements is incorrect?
   

   [A] Corrosion of copper takes place by contact with air and water.
   [B] The melting point and the boiling point of metals are low. 
   [C] Carbonate containing ores are converted to metal oxide by calcination. 
   [D] A more reactive metal displaces a less reactive metal from its solution.

9. Which alloy is used to solder electric wires?
   

   [A] Copper + zinc [B] Aluminium + magnesium [C] Lead + tin [D] Copper + tin

10. Which metal is available in highest proportion on the earth?
    

    [A] Iron [B] Copper [C] Aluminum [D] Silver

11. Which metal is used in thermometer?
    

    [A] Silver [B] Mercury [C] Sodium [D] Copper

12. Which of the following substances is hygroscopic?
    

    [A] Cryolite [B] Feldspar [C] Anhydrous calcium chloride [D] Slag

13. How many elements are known till today?
    

    [A] 112 [B] 113 [C] 114 [D] 115

14. Most of the elements are found in the form of...
    

    [A] metals [B] nonmetals [C] metalloids [D] gases

15. Which metal is generally used in packaging of food materials?
    

    [A] Copper [B] Iron [C] Aluminium [D] Zinc

16. Which of the following is not an inert metal?
    

    [A] Gold [B] Silver [C] Tin [D] Platinum

17. Which of the following metals is used for protection from radiation?
    

    [A] Gold [B] Lead [C] Silver [D] Aluminium

18. Which of the following is considered a noble metal?
    

    [A] Aluminium [B] Silver [C] Copper [D] Sodium

19. Which of the following metals is/are available in free state in nature?
    

    [A] Gold [B] Silver [C] Platinum [D] All three

20. The formula of siderite is...
    

    [A] Fe2O3 [B] Fe3O4 [C] FeCO3 [D] FeS2

21. The formula of bauxite is...
    

    [A] Al2O3 [B] Al2O3.2H2O [C] NaAlO2 [D] Na2AlF6

22. Malachite is an ore of...
    

    [A] iron [B] silver [C] copper [D] calcium

23. Which of the following is not an ore of calcium?
    

    [A] Limestone [B] Dolomite [C] Gypsum [D] Siderite

24. The formula of gypsum is...
    

    [A] CaSO4.2H2O [B] CaCO3 [C] CaSO4.7H2O [D] Ca(OH)2

25. Which of the following methods is based on the difference in densities of ore and impurity?
    

    [A] Centrifugation [B] Liquefaction [C] Froth floatation [D] Pulverizing

26. Which of the following ores is concentrated by froth floatation?
    

    [A] Bauxite [B] Haematite [C] Copper pyrite [D] Dolomite

27. Sulphide ores are converted to ores containing metal oxide by...
    

    [A] calcination [B] liquefaction [C] smelting [D] roasting

28. Calcination is used to convert...
    

    [A] metal carbonate to metal oxide [B] metal oxide to metal carbonate 
    [C] calcium to calcium chloride [D] metal sulphide to metal oxide

29. Oxide of which of the following metals cannot be reduced by carbon?
    

    [A] Zinc [B] Iron [C] Magnesium [D] Manganese

30. Which of the following methods is not used for refining of metals?
    

    [A] Electrolysis [B] Liquefaction [C] Froth floatation [D] Fractional crystallization

31. During electrolytic refining of a metal the insoluble impurities collected at the bottom of the cell form...
    

    [A] anode [B] anode mud [C] cathode [D] cathode mud

32. What works as anode in electrolytic refining of a metal?
    

    [A] A rod of impure metal [B] A rod of pure metal [C] Graphite [D] Platinum

33. What works as cathode in electrolytic refining of a metal?
    

    [A] A rod of impure metal [B] A rod of pure metal [C] Graphite [D] Platinum

34. Which of the following metals is purified by electrolytic refining?
    

    [A] Iron [B] Lead [C] Tin [D] Copper

35. Liquefaction method is used for refining of metals having...
    

    [A] low boiling point [B] high boiling point [C] low melting point [D] high melting point

36. Which of the following metals is refined by liquefaction method?
    

    [A] Copper [B] Aluminium [C] Mercury [D] Tin

37. Which of the following methods uses the principle of fractional crystallization?
    

    [A] Froth floatation [B] Liquefaction [C] Zone refining [D] Smelting

38. Which of the following metals is purified by zone refining?
    

    [A] Silicon [B] Boron [C] Germanium [D] All three

39. Which of the following is a semi-conductor?
    

    [A] Boron [B] Copper [C] Lead [D] Gold

40. The melting point of alumina is...
    

    [A] 1578 K [B] 1875 K [C] 2348 K [D] 3284 K

41. To bring down the melting point of alumina during Hall-Heroult process, we add ______ and ______.
    

    [A] NaCl, CaF2 [B] Na3AlF6, CaF2 [C] NaCl, Na3AlF6 [D] NaOH, NaCl

42. Carbon (graphite) lining of electrolytic cell works as _____ in Hall-Heroult process.
    

    [A] anode [B] cathode [C] electrolyte [D] thermal stabilizer

43. Alumina is obtained from bauxite by...
    

    [A] Hall-Heroult process [B] Bayer's process [C] Blast furnace [D] Calcination

44. In blast furnace, during the manufacture of iron, the temperature in the bottom region is...
    

    [A] 1000 K [B] 1173 K [C] 1973 K [D] 2223 K

45. What is the formula of slag formed in blast furnace?
    

    [A] Ca2SiO3 [B] Na2SiO3 [C] Ca2SiO2 [D] CaSiO3

46. In blast furnace, the oxidation of molten iron is prevented by...
    

    [A] CO2 [B] CaCO3 [C] CaSiO3 [D] hot air

47. The activity of metals is determined by...
    

    [A] displacement reaction  [B] combination reaction 
    [C] decomposition reaction [D] reaction with hydrogen

48. The most reactive metal is...
    

    [A] sodium [B] potassium [C] calcium [D] zinc

49. The least reactive metal is...
    

    [A] sodium [B] copper [C] gold [D] lead

50. Which of the following is the true order of reactivity of metals?
    

    [A] Mg>Al>Zn>Fe [B] Mg> Zn>Al>Fe [C] Al>Mg>Fe>Zn [D] Fe>Zn>Al>Mg

51. Which of the following metals exists in liquid form?
    

    [A] Sodium [B] Tin [C] Manganese [D] Gallium

52. Which of the following metals is very soft?
    

    [A] Tin [B] Aluminium [C] Magnesium [D] Potassium

53. We can prepare about ______ long wire from 1 gram of gold.
    

    [A] 500 m [B] 1000 m [C] 2000 m [D] 5000 m

54. Which of the following metals is a poor conductor of heat and electricity?
    

    [A] Gold [B] Cobalt [C] Sodium [D] Lead

55. The melting point of iron is...
    

    [A] 1218 K [B] 1281 K [C] 1812 K [D] 2181 K

56. Generally metals form _____ oxides.
    

    [A] acidic [B] basic [C] neutral [D] acidic and neutral

57. Which of the following is an amphoteric oxide?
    

    [A] Al2O3 [B] Na2O [C] CaO [D] Fe2O3

58. Which of the following metals does not react with cold water?
    

    [A] Sodium [B] Potassium [C] Magnesium [D] Calcium

59. Stainless steel contains...
    

    [A] 70% Fe, 10% Cr, 20% Ni [B] 70% Fe, 20% cr, 10% Ni
    [C] 20% Fe, 10% Cr, 70% Ni [D] 10% Fe, 20% Cr, 70% Ni

60. An alloy containing _____ is called amalgam.
    

    [A] zinc [B] aluminium [C] mercury [D] tin

61. Brass is an alloy of...
    

    [A] iron and zinc [B] copper and tin [C] iron and nickel [D] copper and zinc

62. Bronze is an alloy of...
    

    [A] iron and zinc [B] copper and tin [C] iron and nickel [D] copper and zinc

63. Which of the following alloys is used in preparing surgical instruments?
    

    [A] Stainless steel [B] Brass [C] Bronze [D] Magnalium

64. Which alloy is used in preparing scientific balance?
    

    [A] Stainless steel [B] Brass [C] Duralumin [D] Magnalium

65. 22 carat gold contains about _____% gold.
    

    [A] 22 [B] 78.4 [C] 86.5 [D] 91.6

66. 24 carat gold contains...
    

    [A] 24 parts gold, 2 parts copper [B] 22 parts gold, 2 parts copper 
    [C] 24 parts gold, 2 parts silver [D] None of the three

67. What is the chemical formula of copper glance?
    

    [A] CuFeS2 [B] Cu2S [C] CuCl2 [D] Cu(OH)2

68. Which of the following particles are wetted by turpentine?
    

    [A] Oxide ore particles    [B] Sand particles 
    [C] Carbonate ore particles [D] Sulphide ore particles

69. Which of the following is not a chemical reducing agent?
    

    [A] Sulphur [B] Aluminium [C] Carbon [D] Carbon monoxide

70. What is the concentration of sodium hydroxide used in Bayer's process?
    

    [A] 40% [B] 45% [C] 54% [D] 66%

71. Which of the following metals can be cut with a knife?
    

    [A] Magnesium [B] Manganese [C] Antimony [D] Sodium

72. Which metal is used in thermometers?
    

    [A] Mercury [B] Silver [C] Platinum [D] Aluminium

73. For concentration of ore of which of the following metals is magnetic separation method used?
    

    [A] Copper [B] Iron [C] Aluminium [D] Tin

74. The chemical formula of rust is...
    

    [A] FeO [B] Fe3O4 [C] Fe2O3.xH2O [D] FeSO4

75. A thin layer of _____ is deposited on iron for galvanization.
    

    [A] Al [B] Zn [C] Cr [D] Ni

76. Addition of small amount of _____ increases the hardness of iron.
    

    [A] C [B] Al [C] Zn [D] Sn

77. Which metal is added to gold used for making ornaments?
    

    [A] Copper [B] Silver [C] Copper or silver [D] Aluminium

78. Which of the following alloys is used for making statues and medals?
    

    [A] Brass [B] Duralumin [C] Magnalium [D] Bronze

79. Which of the following alloy is used in soldering of electric wires?
    

    [A] Lead + tin [B] Copper + zinc [C] Zinc + tin [D] Copper + tin

80. Aqueous solution of K₂O is...
    

    [A] acidic [B] basic [C] neutral [D] amphoteric

81. Which of the following alloys is used for manufacturing pressure c ookers?
    

    [A] Brass [B] Duralumin [C] Bronze [D] Magnalium

82. Which phenomenon is seen in electroplating process for copper?
    

    [A] Positive electrode increases 
    [B] Positive electrode decreases
    [C] The concentration of Cu+2 increases in the electrolyte
    [D] The concentration of Cu+2 decreases in the electrolyte

83. 
    

ANSWERS

(1) A (2) B (3) C (4) C (5) D (6) D (7) B (8) B (9) C (10) C (11) B (12) C (13) C (14) A (15) C (16) C (17) B (18) B (19) D (20) C (21) B (22) C (23) D (24) A (25) A (26) C (27) D (28) A (29) C (30) C (31) B (32) A (33) B (34) D (35) C (36) D (37) C (38) D (39) A (40) C (41) B (42) B (43) B (44) C (45) D (46) C (47) A (48) B (49) C (50) A (51) D (52) D (53) C (54) D (55) C (56) B (57) A (58) C (59) B (60) C (61) D (62) B (63) A (64) D (65) D (66) D (67) B (68) D (69) A (70) B (71) D (72) A (73) B (74) C (75) B (76) A (77) C (78) D (79) A (80) B (81) B (82) B (83) (84) (85) (86) (87) (88) (89) (90) (91) (92) (93) (94) (95) (96) (97) (98) (99) (100)