Electrolysis Cell And Batteries MCQs In English

 

1. The current flow through electrolyte is due to the movement of
(A) ions
(B) holes
(C) electrons
(D) none of the above
Ans: (A)

2. If a lead-acid cell is discharged below 1.8 V the following will happen.
(A) Capacity of cell will reduce
(B) Sulphation of plates will occur
(C) Internal resistance will increase
(D) All above will occur
Ans: (D)

3. Each cell has a vent cap
(A) to allow gases out when the cell is on charge
(B) to add water to the cell if needed
(C) to check the level of electrolyte
(D) to do all above functions
Ans: (D)

4. Following will occur if level of electrolyte falls below plates
(A) capacity of the cell is reduced
(B) life of the cell is reduced
(C) open plates are converted to lead sulphate
(D) all above
Ans: (D)

5. Which of the following battery is used for air-craft ?
(A) Lead-acid battery
(B) Nickel-iron battery
(C) Dry cell battery
(D) Silver oxide battery
Ans: (B)

6. Cells are connected in parallel to
(A) increase the efficiency
(B) increase the current capacity
(C) increase the voltage output
(D) increase the internal resistance
Ans: (B)

7. In a battery cover is placed over the element and sealed to the top of the battery container. This is done
(A) to reduce evaporation of water from electrolyte
(B) to exclude dirt and foreign matter from the electrolyte
(C) to discharge both of the above functions
(D) to discharge none of the above functions
Ans: (C)

8. Level of electrolyte in a cell should be _____ the level of plates
(A) below
(B) equal to
(C) above
(D) none of the above
Ans: (C)

9. Under normal charging rate, the charging current should be
(A) 10% of capacity
(B) 20% of capacity
(C) 30% of capacity
(D) 40% of capacity
Ans: (A)

10. Satellite power requirement is provided through
(A) solar cells
(B) dry cells
(C) nickel-cadmium cells
(D) lead-acid batteries
Ans: (A)

11. While preparing electrolyte for a lead-acid battery

(A) water is poured into acid
(B) acid is poured into water
(C) anyone of the two can be added to other chemical
(D) none of the above
Ans: (B)

12. When two batteries are connected in parallel, it should be ensured that
(A) they have same e.m.f.
(B) they have same make
(C) they have same ampere-hour capacity
(D) they have identical internal resistance
Ans: (A)

13. A battery of 6 cells will show a drop of _____ volts from fully charged state to fully discharged state.
(A) 1.0
(B) 1.5
(C) 2.4
(D) 2.9
Ans: (C)

14. Which of the following primary cells has the highest voltage ?
(A) Manganese-alkaline

(B) Carbon-zinc
(C) Lithium
(D) Mercury
Ans: (C)

15. Chargmg of sulphated battery produces ____ heat.
(A) no
(B) very little
(C) less
(D) more
Ans: (D)

16. Excessive charging a battery tends to
(A) produce gassing
(B) increase the internal resistance of the battery
(C) to corrode the positive plates into lead peroxide thereby weakening them physically
(D) bring about all above changes
Ans: (D)

17. Shelf life of a small dry cell is
(A) equal to that of large dry cell
(B) less than that of large dry cell
(C) more than that of large dry cell
(D) none of the above
Ans: (B)

18. Hydrogen evolved during charging produces explosive mixture when it is more than
(A) 2%
(B) 4%
(C) 6%
(D) 8%
Ans: (D)

19. In a lead-acid battery the energy is stored in the form of
(A) charged ions
(B) chemical energy
(C) electrostatic energy
(D) electromagnetic energy
Ans: (B)

20. Extent of corrosion in the underground metal work depends upon
(A) amount of moisture
(B) type of metals
(C) type of soil chemicals
(D) all above factors
Ans: (D)

21. Charging a sulphated battery at high rate results in

(A) boiling of electrolyte due to gassing

(B) warping of plates

(C) damage to separators, cell caps covers and battery case due to excessive temperature

(D) all above

Ans: (D)

22. Which of the following is incorrect ?

(A) A storage cell has a reversible chemical reaction

(B) A lead-acid cell can be recharged

(C) A carbon-zinc cell has unlimited shelf life

(D) A primary cell has an irreversible chemical reaction

Ans: (C)

23. Which of the following has lower sp. gravity V

(A) Dilute H2S04

(B) Concentrated H2SO4

(C) Water

(D) Any of the above

Ans: (C)

24. Petroleum jelly is applied to the electrical connections to the lead-acid battery

(A) prevent local heating

(B) prevent short-circuiting

(C) reduce path resistance

(D) prevent corrosion

Ans: (D)

25 _____ of electrolyte indicates the state of charge of the battery

(A) colour

(B) mass

(C) viscosity

(D) specific gravity

Ans: (D)

26. The following indicate that battery on charge has attained full charge

(A) colour of electrode

(B) gassing

(C) specific gravity

(D) all above

Ans: (D)

27. Which among the following constitutes the major load for an automobile battery ?

(A) Brake light

(B) Self starter

(C) Parking lights

(D) Spark plugs

Ans: (B)

28. Specific gravity of electrolyte in Edison cell is

(A) 0.8

(B) 0.95

(C) 1.1

(D) 1.21

Ans: (D)

29. All the electrical connections between the battery and vehicle should be by

(A) thin aluminium wires

(B) thin copper wires

(C) rigid cables

(D) flexible cables

Ans: (D)

30. Persons preparing electrolyte should wear

(A) goggles or other face shield

(B) rubber

(C) rubber boots and gloves

(D) all above safety devices

Ans: (D)

31. A constant-voltage generator has
(A) minimum efficiency
(B) minimum current capacity
(C) low internal resistance
(D) high internal resistance
Ans: (C)

32. 48 ampere-hour capacity would deliver a current of
(A) 48 amperes for 1 hour
(B) 24 amperes for 2 hours
(C) 8 amperes for 6 hours
(D) 6 amperes for 8 hours
Ans: (D)

33. Mercury cell has which of the following characteristics ?
(A) Flat discharge current-voltage curve
(B) High power to weight ratio
(C) Comparatively longer shelf life under adverse conditions of high temperature and humidity
(D) All of the above
Ans: (D)

34. Which of the following factors adversely affects the capacity of the lead acid battery ?
(A) Temperature of surroundings
(B) Specific gravity of electrolyte
(C) Rate of discharge
(D) All of the above
Ans: (D)

35. Internal resistance of a cell is reduced by
(A) using vent plug to permit gas formed during discharge
(B) increasing the plate area
(C) putting plates very close together
(D) all above methods
Ans: (D)

36. Trickle charging of a storage battery helps to
(A) maintain proper electrolyte level
(B) increase its reserve capacity
(C) prevent sulphation
(D) keep it fresh and fully charged
Ans: (D)

37. It is noticed that durum charging
(A) there is a rise in voltage
(B) energy is absorbed by the cell
(C) specific gravity of H2SO4 is increased
(D) the anode becomes chocolate brown in colour (PbCfe) and cathode becomes grey metallic lead (Pb)
(E) all of the above
Ans: (E)

38. Which of the following cell has a. reversible chemical reaction ?
(A) Lead-acid
(B) Mercury oxide
(C) Carbon-zinc
(D) Silver-oxide
Ans: (A)

39. Batteries are charged by
(A) rectifiers
(B) engine generator sets
(C) motor generator sets
(D) any one of the above methods
Ans: (D)

40. Cell short circuit results in
(A) low specific gravity electrolyte
(B) abnormal high temperature
(C) reduced gassing on charge
(D) all above
Ans: (D)

41. The capacity of a battery is expressed in terms of
(A) current rating
(B) voltage rating
(e) ampere-hour rating
(D) none of the above
Ans: (C)

42. During the charging and discharging of a nickel-iron cell
(A) corrosive fumes are produced
(B) water is neither formed nor absorbed
(C) nickel hydroxide remains unsplit
(D) its e.m.f. remains constant
Ans: (B)

43. Those substances of the cell which take active part in chemical combination and hence produce electricity during charging or discharging are known as______materials.
(A) passive
(B) active
(C) redundant
(D) inert
Ans: (B)

44. The capacity of a lead-acid cell is measured in
(A) amperes
(B) ampere-hours
(C) watts
(D) watt-hours
Ans: (B)

45. The capacity of a lead-acid cell depends on
(A) rate of discharge
(B) temperature
(C) density of electrolyte
(D) quantity of active materials
(E) all above
Ans: E

46. The internal resistance of a lead-acid cell is that of Edison cell
(A) less than
(B) more than
(C) equal to
(D) none of the above
Ans: (A)

47. Electrolyte used in an Edison cell is
(A) NaOH
(B) KOH
(C) HC1
(D) HN03
Ans: (B)

48. Life of the Edison cell is at least
(A) five years
(B) seven years
(C) eight years
(D) ten years
Ans: (A)

49. A dead storage battery can be revived by
(A) adding distilled water
(6) adding so-called battery restorer
(C) a dose of H2SO4
(D) none of the above
Ans: (D)

50. As compared to a lead-acid cell, the efficiency of a nickel-iron cell is less due to its
(A) compactness
(B) lower e.m.f.
(C) small quantity of electrolyte used
(D) higher internal resistance
Ans: (D)

51. The specific gravity of electrolyte is measured by
(A) manometer
(B) a mechanical gauge
(C) hydrometer
(D) psychrometer
Ans: (C)

52. Over charging
(A) produces excessive gassing
(B) loosens the active material
(C) increases the temperature resulting in buckling of plates
(D) all above
Ans: (D)

53. Undercharging
(A) reduces specific gravity of the electrolyte
(B) increases specific gravity of the electrolyte
(C) produces excessive gassing
(D) increases the temperature
Ans: (A)

54. “The mass of an ion liberated at an electrode is directly proportional to the quantity of electricity”.
The above statement is associated with
(A) Newton’s law
(B) Faraday’s law of electromagnetic
(C) Faraday’s law of electrolysis
(D) Gauss’s law
Ans: (C)

55. The charge required to liberate one gram equivalent of any substance is known as ______ constant
(A) time
(B) Faraday’s
(C) Boltzmann

(D) none of above
Ans: (B)

56. When a lead-acid battery is in fully charged condition, the color of its positive plate is
(A) dark grey
(B) brown
(C) dark brown
(D) none of above
Ans: (C)

57. The active materials of a nickel-iron battery are
(A) nickel hydroxide
(6) powdered iron and its oxide
(C) 21% solution of KOH
(D) all of the above
Ans: (D)

58. The ratio of ampere-hour efficiency to watt-hour efficiency of a lead-acid cell is
(A) just one
(B) always greater than one
(C) always less than one
(D) none of the above.
Ans: (B)

59. The best indication about the state of charge on a lead-acid battery is given by
(A) output voltage
(B) temperature of electrolyte
(C) specific gravity of electrolyte
(D) none of the above
Ans: (C)

60. As compared to constant-current system, the constant-voltage system of charging a lead acid cell has the advantage of
(A) reducing time of charging
(B) increasing cell capacity
(C) both (A) and (B)
(D) avoiding excessive gassing
Ans: (C)

61. In a lead-acid cell dilute sulfuric acid (electrolyte) approximately comprises the following
(A) one part H2O, three parts H2SO4
(B) two parts H2O, two parts H2SO4
(C) three parts H2O, one part H2SO4
(D) all H2S04
Ans: (C)

62. The ampere-hour efficiency of a leadacid cell is normally between
(A) 20 to 30%
(B) 40 to 50%
(C) 60 to 70%
(D) 90 to 95%
Ans: (D)

63. The watt-hour efficiency of a lead-acid cell varies between
(A) 25 to 35%
(B) 40 to 60%
(C) 70 to 80%
(D) 90 to 95%
Ans: (C)

64. The e.m.f. of an Edison cell, when fully charged, is nearly
(A) 1.4 V
(B) 1 V
(C) 0.9 V
(D) 0.8 V
Ans: (A)

65. The internal resistance of an alkali cell is nearly _____ times that of the lead-acid cell.
(A) two
(B) three
(C) four
(D) five
Ans: (D)

66. The average charging voltage for alkali cell is about
(A) 1 V
(B) 1.2 V
(C) 1.7 V
(D) 2.1 V
Ans: (C)

67. On the average the ampere-hour efficiency of an Edison cell is about
(A) 40%
(B) 60%
(C) 70%
(D) 80%
Ans: (D)

68. The active material of the positive plates of silver-zinc batteries is
(A) silver oxide
(B) lead oxide
(C) lead
(D) zinc powder
Ans: (A)

69. Lead-acid cell has a life of nearly charges and discharges
(A) 500
(B) 700
(C) 1000
(D) 1250
Ans: (D)

70. Electrolyte used in a lead-acid cell is
(A) NaOH
(B) onlyH2S04
(C) only water
(D) dilute H2SO4
Ans: (D)

71. Negative plate of an Edison cell is made of
(A) copper
(B) lead
(C) iron
(D) silver oxide
Ans: (C)

72. The open circuit voltage of any storage cell depends wholly upon
(A) its chemical constituents
(B) on the strength of its electrolyte
(C) its temperature
(D) all above
Ans: (D)

73. During the charging of a lead-acid cell
(A) its voltage increases
(B) it gives out energy
(C) its cathode becomes dark chocolate brown in colour
(D) specific gravity of H2SO4 decreases
Ans: (A)

74. The capacity of a lead-acid cell does not depend on its
(A) temperature
(B) rate of charge
(C) rate of discharge
(D) quantity of active material
Ans: (B)

75. During charging the specific gravity of the electrolyte of a lead-acid battery
(A) increases
(B) decreases
(C) remains the same
(D) becomes zero
Ans: (A)

76. The active materials on the positive and negative plates of a fully charged lead-acid battery are
(A) lead and lead peroxide
(B) lead sulphate and lead
(C) lead peroxide and lead
(D) none of the above
Ans: (C)

77. The storage battery generally used in electric power station is
(A) nickel-cadmium battery
(B) zinc-carbon battery
(C) lead-acid battery
(D) none of the above
Ans: (C)

78. The output voltage of a charger is
(A) less than the battery voltage
(B) higher than the battery voltage
(C) the same as the battery voltage
(D) none of the above
Ans: (B)

79. Cells are connected in series in order to
(A) increase the voltage rating
(6) increase the current rating
(C) increase the life of the cells
(D) none of the above
Ans: (A)

80. Five 2 V cells are connected in parallel. The output voltage is
(A) 1 V
(6) 1.5 V
(C) 1.75 V
(D) 2 V
Ans: (D)