Chapter-2 Solutions MCQs
Q 41.: The mass % of NaOH in 1.25 molal NaOH solution is:
(A) 1.25 %
(B) 3.50 %
(C) 4.76 %
(D) 5.28 %
Option – C
Q 42.: 60 mL of 0.2 N H2SO4 , 10 mL of 0.5 N HNO3 and 30 mL of 0.1 N HCl are mixed together. The normality of the resulting mixture is:
(A) 0.1 N
(B) 0.2 N
(C) 0.3 N
(D) 0.4 N
Option – B
Q 43.: The molarity of a solution obtained by mixing 800 mL of 0.5 M HCl with 200 mL of 1 M HCl will be:
(A) 0.6 M
(B) 0.8 M
(C) 0.2 M
(D) 0.4 M
Option – A
Q 44.: Two bottles ‘A’ and ‘B’ contains 1 M and 1 m aqueous solution of H2SO4 respectively.
(A) ‘A’ is more concentrated than ‘B’
(B) ‘B’ is more concentrated than ‘A’
(C) Concentration of ‘A’ is equal to concentration of ‘B’
(D) It is not possible to compare the concentration
Option – A
Q 45.: The volume of water is to be added to 100 cm3 of 0.5 N H2SO4 to get decinormal concentration is :
(A) 400 mL
(B) 450 mL
(C) 500 mL
(D) 550 mL
Option – A
Q 46.: 10 mL of 0.1 N monobasic acid is required to neutralised 15 mL of NaOH solution whose normality is :
(A) 1.5 N
(B) 0.15 N
(C) 0.066 N
(D) 0.66 N
Option – C
Q 47.: Concentrated H2SO4 is 98% by mass and has density 1.80 gm/mL. Volume of acid required to make 1 L of 0.1 M H2SO4 solution is :
(A) 11.01 mL
(B) 16.35 mL
(C) 8.35 mL
(D) 5.55 mL
Option – D
Q 48.: An aqueous solution of glucose is 10 % in strength. The volume in which 1 mole of it is dissolved will be :
(A) 18 L
(B) 9 L
(C) 4.5 L
(D) 1.8 L
Option – D
Q 49.: The volume of 10 N and 4 N HCl required to make 1 L of 7 N HCl are :
(A) 0.60 L of 10 N HCl and 0.40 L of 4 N HCl
(B) 0.50 L of 10 N HCl and 0.50 L of 4 N HCl
(C) 0.80 L of 10 N HCl and 0.20 L of 4 N HCl
(D) 0.25 L of 10 N HCl and 0.75 L of 4 N HCl
Option – B
Q 50.: Mole fraction of a solute in benzene is 0.2 then find molality of solute.
(A) 2.2 m
(B) 3.2 m
(C) 3.6 m
(D) 4.2 m
Option – B
Q 51.: To prepare a solution of concentration of 0.03 gm/mL of AgNO3, what amount of AgNO3 should be added in 60 mL of solution ?
(A) 0.8 gm
(B) 0.18 gm
(C) 1.8 gm
(D) None of these
Option – C
Q 52.: How much volume of 1 M H2SO4 is required to neutralise 20 mL of 1 M NaOH ?
(A) 10 mL
(B) 15 mL
(C) 20 mL
(D) 25 mL
Option – A
Q 53.: Vapour pressure of chloroform (CHCl3) and dichloromethane (CH2Cl2) at 25 °C are 200 mmHg and 41.5 mmHg respectively. Vapour pressure of the solution obtained by mixing 25.5 grams of CHCl3 and 40.0 grams of CH2Cl2 at the same temperature will be :
(A) 173.9 mmHg
(B) 375.9 mmHg
(C) 615.0 mmHg
(D) 90.63 mmHg
Option – D
Q 54.: The system that forms maximum boiling azeotrope is :
(A) Ethanol and Acetone
(B) Carbon disulphide and acetone
(C) Acetone and chloroform
(D) Benzene and toluene
Option – C
Q 55.: Among the following, the azeotropic mixture is :
(A) C2H5Br + C2H5Cl
(B) CCl4 + CHCl3
(C) C6H14 + C7H16
(D) C6H5Br + C6H5Cl
Option – B
Q 56.: The vapour pressure of pure solvent is 0.8 mmHg at a particular temperature. On addition of a non-volatile solute ‘A’ the vapour pressure of solution become 0.6 mmHg. The mole fraction of component ‘A’ is :
(A) 0.75
(B) 0.52
(C) 0.35
(D) 0.25
Option – D
Q 57.: At 300 K, the vapour pressure of an ideal solution containing 1 mole of liquid ‘A’ and 2 moles of liquid ‘B’ is 500 mmHg. The vapour pressure of the solution increases by 25 mmHg, If one more mole of ‘B’ is added to the above ideal solution at 300 K. Then the vapour pressure of ‘A’ in its pure state is :
(A) 200 mmHg
(B) 250 mmHg
(C) 300 mmHg
(D) 600 mmHg
Option – C
Q 58.: Henry’s law constant of oxygen is 1.4 × 10-3 mol L-1 atm-1 at 298 K. How much of oxygen is dissolved in 100 mL at 298 K when the partial pressure of oxygen is 0.5 atm ?
(A) 2.24 mg
(B) 3.2 mg
(C) 1.4 mg
(D) 2.82 mg
Option – A
Q 59.: At 300 K two pure liquid ‘A’ and ‘B’ have vapour pressure respectively 150 mmHg and 100 mmHg. In an equimolar liquid mixture of ‘A’ and ‘B’, the mole fraction of ‘B’ in the vapour mixture at this temperature is :
(A) 0.8
(B) 0.6
(C) 0.5
(D) 0.4
Option – D
Q 60.: Vapour pressure of pure ‘A’ is 70 mmHg at 298 K. It forms an ideal solution with ‘B’ in which mole fraction of ‘A’ is 0.8. If the vapour pressure of the solution is 84 mmHg at 298 K, the vapour pressure of pure ‘B’ at 298 K is :
(A) 140 mmHg
(B) 70 mmHg
(C) 56 mmHg
(D) 28 mmHg
Option – A
Q 61.: Which of the following liquid pairs show a positive deviation from Raoult’s law ?
(A) Water and Nitric acid
(B) Benzene and Methanol
(C) Water and Hydrochloric acid
(D) Acetone and Chloroform
Option – B
Q 62.: At 298 K, the total pressure of an ideal solution obtained by mixing 3 moles of ‘A’ and 2 moles of ‘B’ is 184 torr. What is the vapour pressure (in torr) of pure ‘B’ at the same temperature ? (Vapour pressure of ‘A’ at 298 K is 200 torr)
(A) 100
(B) 120
(C) 140
(D) 160
Option – D
Q 63.: If two substances ‘A’ and ‘B’ have vapour pressure in pure respectively 1 : 2 and have mole fraction in solution 1 : 2 respectively then mole fraction of ‘A’ in vapour is :
(A) 0.1
(B) 0.2
(C) 0.3
(D) 0.52
Option – B
Q 64.: If ‘α’ is the degree of dissociation of Na2SO4 then van’t Hoff factor (i) used for calculating the molecular mass is :
(A) 1 + α
(B) 1 − α
(C) 1 + 2α
(D) 1 − 2α
Option – C
Q 65.: Distribution Law was given by :
(A) Nernst
(B) Ostwald
(C) Henry
(D) Van’t Hoff
Option – A
(A) Phenylacetic acid exists as such in benzene
(B) Phenylacetic acid undergo partial ionisation in benzene
(C) Phenylacetic acid undergo complete ionisation in benzene
(D) Phenylacetic acid dimerises in benzene
Option – D
Q 67.: What happens when an egg is kept in saturated solution of NaCl after removing its hard shell in dilute HCl ?
(A) Egg will shrink
(B) Egg will swell
(C) Egg will remain same
(D) Egg will first shrink and then swell
Option – A
Q 68.: What happens to freezing point to benzene when naphthalene is added ?
(A) Increases
(B) Decreases
(C) Remains unchanged
(D) First increases and then decreases
Option – B
Q 69.: What is the freezing point of a solution containing 8.1 gm HBr in 100 gm Water assuming the acid to be 90 % ionised ? (Kf for water is 1.86 K/mol)
(A) 0 °C
(B) 0.85 °C
(C) 3.53 °C
(D) 5.62 °C
Option – C
Q 70.: Dissolution of 1.5 gm of a non-volatile solute (molecular weight = 60) in 250 gm of a solvent reduces its freezing point by 0.01 °C. Find the molal depression constant of the solvent.
(A) 0.1
(B) 0.01
(C) 0.001
(D) 0.0001
Option – A
Q 71.: 20 gm of a non-volatile solute is added to 500 gm of solvent. Freezing point of pure solvent and solution are 5.48 °C and 4.47 °C. Molecular mass of the solute is: (Given Kf is 1.93 °C/m)
(A) 70.6
(B) 73.2
(C) 75.2
(D) 76.4
Option – D
Q 72.: A 0.2 molal HX acid ionises 20 % in water. (Kf = 1.86) Freezing point of the solution is :
(A) −0.45
(B) −0.50
(C) −0.55
(D) −0.60
Option – A
Q 73.: Which of the following can be measured by the Ostwald-Walker dynamic method ?
(A) Vapour pressure of the solvent
(B) Lowering of Vapour pressure
(C) Relative lowering of vapour pressure
(D) All of the above
Option – C
Q 74.: Camphor is often used in molecular mass determination because
(A) It is readily available
(B) It has a very high cryoscopic constant
(C) It is volatile in nature
(D) It is solvent for organic substances
Option – C
Q 75.: Which of the following colligative properties can provide molar mass of proteins with greater precision ?
(A) Relative lowering of vapour pressure
(B) Elevation in boiling point
(C) Depression in freezing point
(D) Osmotic pressure
Option – D
Q 76.: The mole fraction of solute in 2.5 molal aqueous solution is :
(A) 0.086
(B) 0.068
(C) 0.034
(D) 0.043
Option – D
Q 77.: The volume of 80 % sulphuric acid (H2SO4) by weight required to prepare 1 L of 0.2 M H2SO4 is :
(A) 13.60 mL
(B) 15.60 mL
(C) 9.08 mL
(D) 71.08 mL
Option – A
Q 78.: Which of the following statement is false ?
(A) Both molality and mole fraction do not change with temperature.
(B) 1 M aqueous solution of glucose is more concentrated than 1 m solution.
(C) Sodium amalgam is an example of solid in solid solution.
(D) Parts per million by mass express mass of solute in gram per 103 Kg of the sample.
Option – C
Q 79.: The density of a solution prepared by dissolving 120 gm of urea (molar mass= 60 gm/mol) in 1000 gm of water is 1.15 gm/mL. The molarity of this solution is :
(A) 1.78 M
(B) 2.05 M
(C) 1.02 M
(D) 2.36 M
Option – B
Q 80.: A 6.9 M solution of KOH in water contains 30% by mass of KOH. The density of KOH solution is :
(A) 2.061 gm/mL
(B) 1.288 gm/mL
(C) 1.106 gm/mL
(D) 1.823 gm/mL
Option – B