Quiznetik

Engineering Chemistry | Set 1

1. Hardness of water is due to the presence of salts of

Correct : C. magnesium

2. Select the incorrect statement from the following option.

Correct : D. due to the presence of dissolved hardness- producing salts, the boiling point of water is depressed

3. Select the incorrect statement from the following option.

Correct : D. boiler feed water should also be hard in nature

4. Which of the following is not a unit of hardness?

Correct : B. degree centigrade

5. Hardness of water is conventionally expressed in terms of equivalent amount of

Correct : C. caco3

6. The chemical equivalent of MgSO4 salt is

Correct : D. 70,000

7. 1 ppm =

Correct : C. 0.10fr

8. How many grams of MgCO3 dissolved per litre gives 84 ppm hardness?

Correct : A. 70.56 mg/l

9. EDTA method for hardness determination is a less accurate and inconvenient procedure.

Correct : B. false

10. Estimation of hardness can be determined by                  types.

Correct : A. 2

11. Total hardness of water can be determined by titrating the fixed volume of water against the standard                        solution.

Correct : D. alcoholic soap

12. The sodium soap will precipitate all the hardness causing ions into their respective

Correct : C. stereates

13. The water which form lather directly with the soap is called

Correct : B. soft water

14. EDTA method is also called as

Correct : A. complexometric titration

15. The indicator used in the EDTA method is

Correct : D. erichrome black t

16. The change in colour is sharper at the PH of

Correct : B. 10

17. At PH=10, the metal dye complex has the colour

Correct : A. wine red

18. To prepare EDTA solution                     grams of EDTA is dissolved in the one litre of water.

Correct : D. 4

19. drops of indicator is used in the EDTA method.

Correct : A. 1 to 2 drops

20. The buffer used in the EDTA solution must have the PH of

Correct : C. 10

21. The standard hard water is prepared such that each ml must contain                  mg of CaCO3.

Correct : A. 1

22. Water is mainly used in boilers for the generation of

Correct : C. steam

23. Which of the following is not a result of the excess of impurity in boiler-feed?

Correct : B. decomposition

24. The scales decrease the efficiency of boiler and chances of explosions are also there.

Correct : A. true

25. Foaming is caused by the formation of

Correct : C. oils and alkalis

26. Corrosion is the decay or disintegration of boiler body material either due to chemical or electrochemical reaction with environment.

Correct : A. true

27. Ion exchange process is also called as

Correct : B. demineralization

28. The operational cost of the ion exchange process is

Correct : B. low

29. The hardness in the ion exchange process is reduced to

Correct : B. 0-2ppm

30. The total                      are removed completely in the ion exchange process.

Correct : B. dissolved solids

31. In ion exchange process, the iron and manganese ions are removed from the water.

Correct : A. true

32. Water softened during                      method will be ideal in boilers.

Correct : B. lime soda method

33. The regeneration of acids and alkalis in ion exchange process is

Correct : B. costlier

34. In ion exchange process, the cation exchange resin is generated by passing

Correct : B. dilute acids

35. In the case of the zeolites, ion exchange process do not function properly because of the

Correct : C. turbidity and suspended matter

36. The initial equipment in the ion exchange process is

Correct : A. more

37. The residual hardness after the treatment of water is about

Correct : D. less than 2pmm

38. The continuous supply of soft water can be provided by having

Correct : A. storage facilities

39. The cost of the resins used in the ion exchange process is

Correct : A. high

40. The mineral free water is not used in

Correct : D. drinking

41. In which process of water softening, ion exchange phenomenon takes place?

Correct : B. zeolite process

42. In which process of water softening, the chemicals are added to remove hardness from water?

Correct : A. lime soda process

43. Zeolites are complex compound of

Correct : C. aluminium, silica and soda

44. The color of the artificial zeolite permutit is

Correct : D. white

45. Natural zeolite is mainly processed from

Correct : B. green sand

46. The color of the natural zeolite is

Correct : A. green

47. The chemical formula of Permutit is

Correct : B. sio2al2o3na2o

48. The zeolite process is unsuitable for water containing iron and manganese.

Correct : A. true

49. The thickness of the layers of filter sand of zeolite softener is

Correct : D. 100cm

50. Salt cannot be separated from brackish water by freezing.

Correct : B. false

51. Electrodialysis is based on the fact that the ions present in saline water migrate towards their respective electrodes under the influence of applied

Correct : D. emf

52. The cation selective membrane is embedded with functional groups of

Correct : B. negative charge

53. Electrodialysis is an electrically driven separation conducted at a very low pressure- driven, size-exclusion filtering process.

Correct : A. true

54. The ion-exchange membrane are electrically conductive and are not permeable to                        flow, even under pressure.

Correct : D. water

55. Select the incorrect statement from the following option.

Correct : D. electrodialysis process is not economical as per capital cost

56. Which one of the following is not a cation exchanger?

Correct : B. triolite

57. The                  the salt rejection, the better the system is performing.

Correct : A. higher

58. What is the osmotic pressure for sea water?

Correct : D. 2.45 mpa

59. Membrane permeation rate increases proportionally to effective pressure.

Correct : A. true

60. RO membranes are made of

Correct : D. polymer

61. Concentrated seawater which is called

Correct : B. brine

62. 7 REVERSE OSMOSIS.

Correct : A. true

63. The upper limit of brine concentration is

Correct : C. 2.5

64. What is the maximum acceptable limit of temperature for RO?

Correct : C. 40˚c

65. What is the design temperature of RO systems?

Correct : B. 25˚c

66. What is the thumb rule to consider for osmotic pressure?

Correct : A. 1 psi for every 86 ppm of na

67. What is the flux considered while designing a reverse osmosis system for treating RO permeate?

Correct : A. 30-40 lmh

68. What is the flux considered while designing a reverse osmosis system for treating bore well water?

Correct : C. 20-30 lmh

69. What is the flux considered while designing a reverse osmosis system for treating surface water?

Correct : A. 15-22 lmh

70. What is the flux considered while designing a reverse osmosis system for treating surface water with UF system?

Correct : B. 20-30 lmh

71. What do you mean by the term “Sorption”?

Correct : A. attachment

72. The desorption curve is higher than the adsorption curve.

Correct : A. true

73. Which of the following isotherm is applicable to physical adsorption?

Correct : C. freundlich

74. Which type of isotherm is given from the figure, Choose from the following options?

Correct : A. type 1 adsorption isotherm

75. Which of the following statements regarding the physical adsorption of a gas on surface of solid is not correct?

Correct : A. on increasing temperature, adsorption increases continuously

76. Which of the following is not characteristic of chemisorption?

Correct : C. it is multilayer phenomenon

77. For an adsorbant-adsorbate system obeying the Langmuir adsorption isotherm, b = 0.48 bar-1 and p = 0.16 bar-1. At what pressure will 50% of the surface be covered?

Correct : B. 0.07 bar

78. Adsorption of methane follows the Langmuir adsorption isotherm at 90K. If p = 1.896cm3g-1bar-1 and b = 0.146bar-1. Calculate the value of θ.

Correct : D. 0.216 bar

79. In Langmuir’s model of adsorption of a gas on a solid surface the mass of gas striking a given area of surface is                             to the pressure of the gas.

Correct : A. proportional

80. The physical process that occurs when gas or liquid molecules are brought into contact with a solid surface and condense on the surface

Correct : B. adsorption

81. Adsorption when interaction between the solid and the condensed molecules is relatively strong as contrasted with physical adsorption.

Correct : B. adsorption

82. The gas molecules are held on solid surface by                    in physical adsorption.

Correct : D. vander waal’s forces

83. The extent of adsorption of a gas on a solid depend on

Correct : D. all of the mentioned

84. Which of the following gases is adsorbed by charcoal?

Correct : A. nh3

85. Langmuir isotherm Mathematical relation for                        that takes place at equilibrium.

Correct : B. adsorption

86. Adsorption process must be

Correct : C. exothermic

87. The rate law for a reaction between the substances A and B is given by rate = K[A]n [B]m. On doubling the concentration of A and halving the concentration of B. What will be the ratio of the new rate of the earlier rate of the reaction?

Correct : D. 2n-m

88. On which factor the rate constant of a reaction does not depend upon?

Correct : D. concentration of reactants and products

89. The rate of reaction, A + B Products, is given by the equation, r = k[A][B]. If B is taken in excess, what would be the order of reaction?

Correct : B. 1

90. In a reaction, 2A2 + B2 → 2A2B, when the reactant A will disappear?

Correct : D. twice the rate that b will decrease

91. The rate of reaction that does not involve gases, is not dependent on

Correct : A. pressure

92. Which is not true for a second order reduction?

Correct : C. time to complete 75% reaction is twice of half-life

93. The rate of decomposition of a substance increases concentration of substance at same temperature. Find out order of reaction.

Correct : B. 2

94. Molecularity of a reaction is equal to the total number of

Correct : B. reactants taking part in elementary step

95. Which of the following statement is incorrect about the molecularity of a reaction?

Correct : D. it can be zero, fractional or integer

96. Which of the following factor does not effect the rate of reaction?

Correct : C. pressure

97. The reaction rate is greatly influenced by

Correct : C. both nature and strength of the reactant molecules

98. The reactions register an increase in rates in the presence of radiations of specific wavelengths.

Correct : A. true

99. Select the correct option from the following option.

Correct : C. catalyst is used to increase the rate of reaction and remains unaltered chemically during the course of reaction

100. Which of the following is not an adsorbent?

Correct : D. dry sponge