1 .Solution & Colligative Properties Q

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SOLUTIONS AND COLLIGATIVE COLLIGATIVE PROPERTIES CET WORKSHEET

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A solution is a) a mixture of two components b) a compound of two components c) A homogenous mixture of two components d) All the above 50 g. of a solvent is dissolved in 0.95 kg of the solvent. The weight percent of the solution is a) 50 b) 0.95 c) 5 d) 0.095 A solution is 0.25% by weight. The weight of the solvent containing 1.25 g of solute would be a) 500 g b) 498.75 g c) 500.25 g d) 501.25 g 200 g of a 5% solution (by weight) of the solute A is mixed with 300 g of a 10% solution (by weight) of solute B. The weight percent of A and B in the mixture are respectively a) 3.33 and 15 b) 5 and 10 c) 2 and 16 d) 6 and 2 Equal volumes of a 10% solution (by weight) of the solute A and 15% solution (by weight) of the solute B are mixed. The weight percent of A and B in the mixture would be respectively a) 5 and 7.5 b) 10 and 15 c) 15 and 10 d) 20 and 30 400 cm3 of water is added to 600 g of a 6% (weight percent) aqueous soln. of a solute. The final weight percent of the solute is a) 10 b) 1.5 c) 9 d) 3.6 2 mole of ethanol is dissolved in 8 mole of water. The mole fraction of water in the solution a) 0.2 b) 0.8 c) 0.4 d) 1 92 g of ethanol is dissolved in 108 g of water. The mole fraction of ethanol in the soln is a) 0.25 b) 0.75 c) 92/108 d) 108/92 4.9 gm of H 2 SO4 is present in 500 cm3 of the solution. Its molarity will be a) 0.2 b) 0.1 c) 0.05 d) 0.025 A centi-molar solution is diluted 10 times. Its molarity would be a) 0.01 b) 0.1 c) 0.001 d) 0.005

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If 20 gm. of sodium hydroxide is dissolved in 1 dm3 of water, the molality of the solution will be a) 0.5 b) 1 c) 0.01 d) 0.2 Which of the following statements is true for a solution ? a) Normality is always equal to molarity b) Normality is always less than molarity c) Molarity is always less than normality d) Molarity is either equal to or less than normality 30 gm of acetic acid is dissolved in 1dm3 of the solvent. The molality of the soln. will be (Given, density of solvent = 1.25 g. cm −3 ) a) 0.4 b) 0.3 c) 0.5 d) 0.45 Colligative properties of a solution are there whose values depend on a) No. of molecules present in it b) No. of ions present in it c) No. of particles present in it d) None of these Which one of the following is a colligative property ? a) Boiling point b) Freezing point c) Vapour pressure d) lowering of vapour pressure Some of the statements are given below A] lowering of vapour pressure is a colligative property B] Freezing point of a soln. depends on its concentration C] Higher the vapour pressure of a liquid, lower is its boiling point D] Vapour pressure of a solution is always more than that of pure solvent. Among the above the true statements are a) only A and B b) only A and C c) A, B and D d) A, B and C If “n” mole of solute are dissolved in “N” mole of solvent and if vapour pressure of pure solvent is ‘P’, then the partial vapour pressure of the solvent in the solution. Will be P nP a) b) n+N n+N NP nP c) d) n+N N Solutions and Colligative Properties

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The vapour pressure of pure solvent and solutions are 120mm and 108mm respectively. The mole fraction of the solvent in the soln is a) 0.1 b) 0.9 c) 120/108 d) 1.08 The vapour pressure of the solution and pure solvent are P and Po respectively. If P/Po is 0.15. then the mole fraction of the solute in the solution is a) 0.85 b) 0.15 c) 1/0.15 d) 1/0.85 In ostwald’s and walkes’s method for determining the lowering of vapour pressure, the loss in weight of solvent bulb is 50 times less than the gain in weight of CaCl2 tubes. The vapour pressure of the soln. would be (Given v.p of pure solvent = 100mm) a) 2 mm b) 0.5 mm c) 98 mm d) 100 mm The 0.1 molar aqueous soln. of glucose boils at 100.160 C . The boiling point of 0.5 molal aqueous soln. of sucrose will be a) 500.800 C b) 100.800 C d) 20.80 C c) 20.160 C Which one of the following aqueous soln. will have the highest boiling point ? a) 0.1 M urea b) 30 g of glucose per dm3 c) 3.42 g of sucrose in 100 ml d) 0.2 M glucose If kb denotes the molal elevation constant of

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water, then the boiling point, of an aqueous soln. containing 36 g. of glucose per dm3 in 0 C will be

2kb  kb    b) 100 +  100 +  10 10     c) (100 + kb) d) (100 + 2 kb) For a solvent kb = 5 K kg mol −1 . Using this solvent the solution records the elevation of boiling point of 0.50 C . The molality of the solution is a) 0.25 b) 0.1 c) 10 d) Unpredictable Which one of the following aqueous solution will have the highest freezing point ? a) 0.1 M urea b) 0.2 M cane sugar c) 6 g of glucose in 100 cm3 d) 1.5 g of urea in 500 cm3

a)

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Solutions and Colligative Properties

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The values of K f for solvents A,B,C and D are 1.86, 1.99, 5.12 and 4.4 K kg mol −1 respectively. The equimolal solutions of a solute in there solvents will have the freezing in order of solvents as a) C > D > B > A b) A > C > D > B c) A > B > D > C d) C > B > A > D The solution containing 6 g of urea (mol. Wt = 60) per dm3 of water and another containing 9 g of solute A per dm3 of water freeze at the same temperature. The molecular weight of ‘A’ is a) 120 b) 90 c) 54 d) 900 Osmosis is the flow, through semi permeable membrane of a) Solvent molecules from pure solvent to solution b) Solvent molecules from a solution of lower concentration to that at hiqher concentration c) Solute molecules from a solution of higher concentration to that at lower concentration d) Both (a) and (b) osmotic pressure is defined as a) The excess pressure which must be applied to a solution to stop osmosis b) The excess pressure which must be applied to a solution to increase its vapour pressure till it becomes equal to the vapour pressure of pure solvent c) The decrease in pressure of the pure solvent till it becomes equal to the vapour pressure of the solution d) All the above When a solution is separated from the solvent by a semi-permeable membrane, the solution rises to maximum height of 10cm. The osmotic pressure of the solution in Pascal is (Given, Density of solution = 1.1 kg dm3 ) a) 1079.1 b) 107.91 c) 10791 d) 10.791 The osmotic pressure of a solution is directly proportional to a) Its molarity b) Its temperature c) Both (a) and (b) d) None of these The isotonic solutions have same a) Molarities b) Osmotic pressure c) Temperatures d) All of these

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A 0.1m solution of a solute A is isotonic with a solution of B containing 1.5 g of it per 100 cm3 . The molecular weight of B is a) 150 b) 15 c) 75 d) 750 A 0.2 M solution of a solute is isotonic with a solution containing a) 3.42 g of sucrose in 100 cm3 b) 18 g of glucose per dm3 c) 6 g of urea in 500 cm3 d) 27 g of fructose per dm3 For isotonic solutions which one of the following is equal ? a) Molality b) Normality c) Weight percent d) Molarity Solution ‘A’ contains 5.85 g of NaCl in 500 cm3 of water and 1 solution B is 0.2 m glucose in water. Temperature being same, which one of the following is true ? a) Both the solutions are isotonic b) A is hypotonic solution with respect to B c) B is hypertonic solution with respect to A d) A is hypertonic solution with respect to B The weight of glucose to be dissolved in 250 cm3 of water, to set a solution which is isotonic with 0.2 M solution of urea, is a) 36 g b) 9 g c) 18 g d) 4.5 g The solutions of electrolytes have higher values of colligative properties than the equimolar solutions of non-electrolytes. This is because a) of ionization of electrolytes b) non-electrolytes do not ionize c) electrolytes ionize to increase the number of particles in the solution d) the number of particles in the solution of electrolytes increases due to ionization and the value of colligative property depends on number of particles in the solution The boiling point of a decimolal aqueous solution of glucose could be (Given kb = 0.52 mol −1 )

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l kg a) 100.520 C b) 99.480 C c) 99.9480 C d) 100.0520 C osmotic pressure of a 0.6% solution of urea is 300mm Hg at 298 k. The osmotic pressure of a 0.2m cane sugar solution at the same temperature would be a) 300 mm b) 600 mm c) 150 mm d) 30 mm

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The vapour pressure of a solvent is decreased by 2.5mm by adding a solute. The mole fraction of the solute in the solution is (Given v. p of pure solvent B = 250 mm) a) 0.1 b) 0.9 c) 0.01 d) 1.01 The relative lowering of vapour pressure in a solution is 0.23. The mole fraction of the solvent in the solution is a) 0.23 b) 0.43 c) 0.77 d) 0.34 The example of solution of liquid in gas is a) Dry air b) Aerated water c) Amalgam d) Moist air The vapour pressure of pure solvent is Po. The mole fraction of a non-volatile solute in the solution is x. The vapour pressure of the solution will be a) Po (1 – x) b) Po / (1 – x) c) Pox d) Po/x The lowering of vapor pressure of solvent occurs a) When the solvent is volatile b) When the solute is non-electrolyte c) When the solute is non-volatile d) In all the above cases Arrange the following aqueous solutions in the order of there increasing boiling points i) 10−4 M NaCl ii) 10−3 M Urea iii) 10 −3 M MgCl2 iv) 10−2 M NaCl a) (i) < (ii) < (iii) < b) (ii) < (i) = (iii) < (iv) (iv) c) (ii) < (i) < (iii) < d) (iv) > (iii) > (i) = (iv) (ii) Which one of the following aqueous solution will have the lowest freezing point ? (Assume complete ionization) a) 0.1 m urea b) 0.1 m NaCl c) 0.2 m sucrose d) 0.15 m BaCl2 If π1 is the osmotic pressure of a solution containing 6 g of acetic acid per dm3 and π2 is that of a solution containing 5.85 g of NaCl per dm3 at the some temperature, then a) π1 < π2 b) π1 > π2 c)

π1 = π2

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2π1 = π2

Solutions and Colligative Properties

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At constant temperature, the osmotic pressure ( π ) and the molarity (M) of the solution are

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related as 1 M 1 c) π α M d) π α M The osmotic pressure ( π ) is given as equal to

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παM

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a) M/RT b) MR/T c) MRT d) RT/M The osmotic pressure (in atm) of a 1 M solution a non-electrolyte at O 0 C will be a) 1 b) 22.4 c) 0.0821 d) 10 Equimolar solutions of urea and KCl are separated by a semi permeable membrane. Which one of the following will take place ? a) No net flow of solvent in either direction b) Solvent will flow from KCl to urea solution c) Solvent will flow from urea to KCl solution d) Nothing can be predicted For NaBr solution, M = 0.5, α = 0.8 and π = 400mm and for Na3 Po4 solution, m =

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Solutions and Colligative Properties

( A + x )0 c

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x  x  d)  A +  k  A+  c 5 5   For water k f = 1.86 K kg mol −1 . Assuming

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complete ionization, the freezing point of 1 molal aqueous solution of KCl would be a) 3.720 c b) −3.720 c 0 c) −1.86 c d) Unpredictable The freezing point of a 0.05 molal solution of a non-electrolyte in water is ( K f = 1.86 K kg mol −1 ) a) 0.0930 c b) 273.093 K c) 272.907 K d) -0.093 K The best solvent to determine the depression of freezing point accurately is that which has a) A low value of K f b)

0.25, α = 0.6 and π = P2 . Temperature being same, the value of P2 will be a) 533.3 atm b) 1200 mm c) 300 mm d) 2133. mm The molecular weights of CaCl2 , NaCl and glucose, as determined from osmotic pressure are A, B and C respectively. Assuming CaCl2 and NaCl to be completely ionized the order observed molecules weights will be a) C > B > A b) A > C > B c) C > A > B d) B > A > C The plant cell will shrink when it is placed in a) A hypertonic soln b) A hypotonic soln c) An isotonic soln d) None of these The molal elevation constant is the ratio of the elevation of boiling point to a) Molarity b) Molality c) Normality d) Mole fraction of solute

The value of Kb for a solvent is x K kg mol −1 , A 0.2m solution, of a non-electrolyte, in this solvent will boil at (Given, B.P of solvent = A 0c )

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A high value of K f

c) A low freezing point d) A high freezing point Molal elevation constant of water is 0.51. The boiling of a decimolal aqueous KCl is hearly equal to a) 100.10 c b) 100.050 c 0 c) 105.1 c d) 101.50 c The elevation of boiling point of a solution of 10g of a binary strong electrolyte (mol. wt = 100) in 100g. of water is ∆T . The value of Kb for water is a) 10 b) 2 c) 2 ∆T d) ∆T / 2 Equal volumes of centimolar solutions of glucose and fructose are mixed. The osmotic pressure of the mixture is a) equal to either of the solution b) less than either of the solution c) more than either of the solution d) the sum of osmotic pressure of individual solution

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The ratio of the value of any colligative property for BaCl2 and Na3 PO4 , assuming α to be same for both, is a) 3 : 4 b) 1 : 4 c) 1 : 2 d) 4 : 3 A 5% solution of glucose is isotonic with a 1% solution of solute A. The mol. wt of A is a) 900 b) 180 c) 36 d) 90 A non-volatile solute lowers the vapour pressure of a solvent by 20 mm when its mole fraction in the solution is 0.3. To obtain a lowering of vapour pressure of 40 mm, the mole fraction of the solvent should be a) 0.6 b) 0.3 c) 0.4 d) 0.15 The osmotic pressure of 1% urea solution ( π1 ) ,

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equal if K b = K f

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a)

π3 > π2 > π1

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a) 5 : 5 : 4 b) 4 : 5 : 4 c) 1 : 0.8 : 1 d) 0.8 : 1 : 1 To 100 ml of a 0.5 M solution, 400 ml of water is added. The final molarity would be a) 0.125 b) 0.1 c) 0.25 d) 0.15 800 ml of 0.1 M H 2 SO4 is mixed with 200 ml

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of 0.8 M H 2 SO4 . The molarity of the mixture. is a) 0.32 b) 0.24 c) 0.2 d) 0.45 400 ml of 0.2 m H 2 SO4 is mixed with 100 ml

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π1 > π2 > π3

d) π2 > π1 > π3 π3 > π1 > π2 One mole of urea is dissolved in 36 g of water. The V.P of the solution and pure water are in the ratio of a) 1 : 1 b) 1 : 3 c) 2 : 3 d) 1 : 2 The elevation of boiling point for 0.1 m sucrose, 0.2 m urea and 0.2 m NaCl are in the ratio of a) 1 : 2 : 4 b) 1 : 2 : 2 c) 1 : 1 : 2 d) 1 : 1 : 4 How much glucose per 100 cm3 should be present to get a solution which would be isotonic with a 3.42% sucrose solution ? a) 18 g b) 9 g c) 1.8 g d) 3.6 g The weight of urea, to be dissolved per dm3 , to get a solution which is isotonic with a 0.1m aqueous solution of BaCl2 ( α = 1) would be c)

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a) c)

108 g 6g

b) d)

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C] Among a set of solution, that which has highest F. pt and will also have highest B. pt. D] Equimolar solutions of all solutes are isotonic Among the above the false statements are a) B, C and D b) A, B and C c) C and D d) B and C Assuming the degree of ionization to be equal the ratio of osmotic pressure of equimolar solutions of Al2 ( SO4 )3 , Na3 PO4 and K 4  Fe ( CN )6 

2% glucose ( π2 ) and 3.42% sucrose solution

( π3 ) , at same temperature are in the order

Some statements are given below : A] In solution of a non-volatile solute, the V.P of solution is equal to partial V.P of solvent B] For a given solution ∆Tb and ∆T f will be

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of 0.1 N H 2 SO4 . The final normality is a) 0.17 b) 0.45 c) 0.25 d) 0.34 The lowering of vapour pressures is 0.1 m aqueous solutions of NaCl, CuSO4 and K 2 SO4 are in the ratio of a) 1 : 2.5 : 1.5 b) 1 : 1 : 3 c) 1 : 1 : 1.5 d) None of these The factor of ∆Tb / kb is equal to a) Molality b) Molarity c) Mole fraction d) None of these Osmotic pressure can be increased by a) Increasing temperature b) Decreasing temperature c) Increasing volume d) All of these Which of the following is not a colligative property ? a) ∆Tb b) π c) K f d) P0 − P Solutions and Colligative Properties

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When a solution is diluted the mole fraction of the solvent a) Decreases b) Increases c) Remains unchanged d) Changes unpredictably When to a solution, the solvent is added, the value of lowering of vapour pressure a) Decreases b) Increases c) Remains unchanged d) Records an unpredictable change A molal solution is that which contains one mole of solute in a) one litr. of solvent b) one litr. of solution c) one kg of solution d) one kg of solvent The osmotic pressure, of a solution of benzoic acid in benzene, is less than expected. This is because a) Benzene is a non-polar solvent b) Benzoic acid is an organic solute c) Benzoic acid is in associated state in benzene d) Benzoic acid gets dissociated in benzene The Raoult’s law of lowering of V.P is best applicable in determination of correct mol. wt. in case of a) Volatile solute in a concentrated solution b) Volatile solute in a dilute solution c) Non-volatile solute in a concentrated solution d) Non-volatile solute in a dilute solution The plot of partial vapour pressure of a volatile component of a solution vs its mole fraction at a constant temp. is a straight line with a) Negative slope b) With positive slope c) With positive slope passing though the origin and reaching a maxima d) With a positive slope and passing through the origin The vapour pressure of a liquid depends on a) Its surface area b) Its volume c) Temperature d) All of these

Solutions and Colligative Properties

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The normal molecular wt. of on electrolyte is M 1 and its molecular wt. obtained from a colligative property is M 2 . Then a) M 1 = 2M 2 b) M 1 > M 2

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d) 2M 1 = M 2 c) M 1 < M 2 Which of the following happens, in case of solution, when the mole fraction of a solute in the solution decreases ? a) V.P increases b) F. pt.. increases c) Osmotic pressure increases d) Both (a) and (b) The molarity of a 10% NaOH solution is a) 2.5 b) 0.5 c) 0.25 d) 0.05 The mole fraction of nitrogen lima mixture of 7 g of N 2 and 16 g of O2 , is a) 0.5 b) 0.75 c) 0.66 d) 0.33 100 ml of 2NHCl is mixed with 400 ml of 5N H 2 SO4 and the mixture is made 2 litr by water. The normality of the resulting mixture is a) 2.2 b) 1.4 c) 1.1 d) 0.7 Which of the following solutions has highest normality ? a) 1 M HCl b) 0.5M H 2 SO4 c) 0.4M H 3 PO4 d) 0.55M H 2 SO4 Colligative properties of a solution depends upon: a) Nature of both solvent and solute b) The relative number of solvent and solute particles c) Nature of solute only d) Nature of solvent only Isotonic solution have the same a) Density b) Molar concentration c) Strength d) Normality