NCERT Class 12 Important Chemistry Solutions Questions with Answers for Board Exam

NCERT Class 12 Important Chemistry Questions with Answers for Exam

NCERT Class 12 Important Chemistry Questions with Answers For 2021 Important Chemistry Questions for Exams Chapter 2 Solution Short Questions with Answer for 2021

NOTE: NCERT Solutions for Class 12 Chemistry : The NCERT solutions provided here will enhance the concepts of the students, as well as suggest alternative methods to solve particular problems to the teachers. So, the target is to direct individuals towards problem solving strategies, rather than solving problems in one prescribed format. The links below provide the detailed solutions for all the Class 12 Chemistry problems

51. Ifa is the degree of dissociation of Na,SO,. Van’t Hoff’s factor () used for calculating the molecular mass is 

(b) 1-a 

(a) 1+a 

(d) 1-20 

(c) 1+2a 

52. The van’t Hoff factor for BaCI, at 0.01M concentration is 1.98. The % dissociation of BaCl, at this concentration is – 

(b) 69 

(a) 49 

(d) 89 

(c) 98 

53. Which of the following does not vary with temperature? 

(b) molarity 

(a) normality 

(d) none of these 

(c) molality 

54. Highest boiling point is found in – 

(b) 0-1M BaCl, 

(a) 0-1 MNaCl 

(d) 0-1M KC. 

(c) 0-1 M sucrosee 

55. Vapour pressure of pure solvent is 0-8 mm of Hg at a particular temperature. On addition of non-volatile solute ‘A’ the vapour pressure of solution become 0-6 mm of Hg. The mole fraction of component A is 

(b) 0-75 

(a) 0-25 

(d) 0-35 

(c) 0-5 

56. The solubility of a gas in a liquid is directly proportional to the pressure of the gas. This statement is 

(b) Van’t Hoff’s law 

(a) Raoult’s law 

(d) None of these 

(c) Henry’s law 

57. An azeotropic mixture of two liquids boils at a lower temperature than either of them when 

(a) it is saturated 

(b) it does not deviate from Raoult’s law 

(c) It shows negative deviation from Raoult’s law 

(d) It shows positive deviation from Raoult’s law 

58. The solubility of a substance is defined as the amount of solute in gram 

(a) present per litre of solution 

(b) present per 100 g solution 

(c)present per 100 g solvent 

(d) present per 100 ml solution 

59. The solubility of a gas in a liquid increase with 

(a)increase in pressure 

(b)decrease in temperature 

(c) increase in amount of liquid 

(d) both (a) and (b) 

60. Normal boiling point of a liquid is that temperature at which vapour pressure of the liquid is equal to 

(a) zero 

(b) 76Omm 

(c) 100mm 

(d) 273mm 

61. Water boils at lower temperature on higher altitudes because 

(a)atmospheric pressure is high there 

(6) hydrogen bond is weaker there 

(c) atmospheric pressure is low there 

(d) none of these 

62. Which of the following is not a property of liquid? 

(a) viscosity 

(b) surface tension 

(C)anisotropy 

(d) evaporation 

63. Which of the following decreases with increase in molecular mass for a liquid? 

(a) Viscosity 

(b) vapour pressure 

(C) boiling point 

(d) surface tension 

64. Semipermeable membrane is that which permits the passage of 

(a) solute molecules only 

(6) solvent molecules only 

(c)both solute and solvent molecules 

(d) 1ons only 

65. The osmotic pressure of a 5% solution of glucose (mol. mass= 180) at 15°C is 

(a) 6.56 atm 

(b) 5 atm 

(c) 6.65 atm 

(d) 3.4h atm 

66. Which of the following has highest osmotic pressure? 

a) 0.1M A, (SO, ),

(b) 0.1M BaCL 

(d) 0.1 M glucose 

(c) 0.1M NaC 

67. A 1.05% (W/v) solution or a substance  was found to be isotonic with o glucose solution the molecular mass of the substance is 

(b) 63 

(a) 6.3 

(d) 10.5 

(c) 36 

68. Which of the following pairs of solutiosolutions are isotonic? 

(a) 0.1M urca and 0.1M NaCI 

(b) 0.1 M NaCl and 0.1M Na, S0, 

(c) 0.1M Ca(NO,), and 0. 1M K,SO, 

(d) 0.1M glucose and 0.2M MgC1 

69. Cryoscopy is related with 

(a) Osmotic pressure of solution 

(b) elevation in boiling point of solution 

(c) depression in freezing point of solution 

(d) none of these 

70. The plant cells will shrink when placed in 

(b) hypotonic solution 

(a) water 

(c) hypertonic solution  

(d) isotonic solution 

71. The study of colligative property is useful for the calculation of 

(a) atomic weight of solute 

(b) molecular weight of solute 

(c) equivalent weight of solute 

(d) all of these 

72. The relative lowering of vapour pressure is equal to mole fraction of the solute. This is known as 

(a) Raoult’s law 

(b) Van’t Hoff’s law 

(c) Ostwald’s law 

(d) Henery’s law 

73. Which of the following solutions will have the lowest vapour pressure ? 

(a) 0.IM Na, PO, 

(b) 0.1M BaCl, 

(c) 0.1MNaCl 

(d) 0.1M urea 

74. 18g glucose is dissolved in 90g water. The relain 1owering of vapour pressure is equal to 

(a) ⅙ 

(b)⅕ 

(C)50/51 

(d)1/51 

75.The vapour pressure of toluene is 20.9mm and benzene is 74.2 mm at same temperature. The total vapour pressure of an equimolar solution of two liquids is 

(b) 37.2mm 

(a) 57.4mm 

(d) 10.4mm 

(c) 47.5mm 

76. Which of the following form an idcal solution ? 

(b) C2 H4 & CCI3 

(a) H,O & HBr 

(c) C6 H12 OH & CCI,

(d) all of these 

77. When a solute is dissolved in a solvent the vapour pressure of the solution is decreased. It causes 

(a) a decrease in B.P. of solution 

(b) an increase in BP of solution 

(c) a decrease in osmotic pressure 

(d)none of these 

78. The vapour pressure of a dilute solution containing solute is not affected by 

(a) degree of dissociation of solute 

(b) melting point of solute 

(c)temperature of solution 

(d) mole fraction of solute 

79.Which of the following precipitate can act as a semipermeable membrane ? 

(a) copper ferrocyanide 

(b) Barium oxalate 

(c) Calcium sulphate 

(d) Nickel sulphate 

80. The osmotic pressure of glucose solution at 27°C is 2.5 atm, the concentration of glucose solution is 

(b) 9gL 

(a) 0.1gL 

(d) 10 g/L 

(c) 18 g/L 

81. Which of the following expression gives the osmotic pressure of a solution. 

(a) π= RT/C  

(b) π= CRT 

(C) π= VRT  

(d) π= RC/T  

82. Which pairs of equimolar solutions will have equal Osmotic pressure. 

(a)glucose and urea

(b) NaCl and urea 

(c) NaCl and glucose

(d) none of these 

83, Boiling point of a solution is independent of 

(a) amount of solute

(b) amount of solution 

(c)nature of solvent

(d) pressure 

84. The elevation in boiling point for one mole of a solute in 1000g solvent is called 

(a)cryoscopic constant 

(b) boiling point constant 

(c)ebullioscopic constant 

(d)freezing point constant 

85. Which of the following methods can not be used to determine the molecular weight of non-volatile solute ? 

(a) Cryoscopic method 

(b) Osmotic pressure 

(c) Ebullioscopic method 

(d) Victor meyer’s method 

ANSWER

51. (c) 52. (a) 53. (c) 54. (b) 5. (a) 56. (c) 57. (d) 58. (c) 59. (d) 60. (b) 61. (c) 62. (c) 63. (b) 64. (b) 65. (a) 66. (a) 67. (b) 68. (c) 69. (c) 70. (c) 71. (b) 72. (a) 73. (a) 74. (d) 75. (c) 76. (b) 77. (b) 78. (b) 79. (a) 80. (c) 81. (b) 82. (a) 83. (b) 84. (c) 85. (d) 

Leave a Comment