Solutions MCQs

 

Solutions

Multiple Choice Questions

  

 

1. On dissolving sugar in water at room temperature solution feels cool to touch. Under which of the following cases dissolution of sugar will be most rapid?
   1.   Sugar crystals in cold water
   2.   Sugar crystals in hot water
   3.   Powdered sugar in cold water
   4.   Powdered sugar in hot water.
2. At equilibrium the rate of dissolution of a solid solute in a volatile liquid solvent is ____
   1.   less than the rate of crystallisation
   2.   greater than the rate of crystallisation
   3.   equal to the rate of crystallisation
   4.   zero.
3. The unit of ebulioscopic constant is
   1.   K kg mol^-1 or K (molality)^-1
   2.   mol kg K^-1 or K^-1 (molality)
   3.   kg mol^-1 K^-1 or K^-1 (molaity)^-1
   4.   K mol kg^-1 or K (molality)
4. A beaker contains a solution of substance ‘A’. Precipitation of substance ‘A’ takes place when small amount of ‘A’ is added to the solution. The solution is ____
   1.   saturated
   2.   supersaturated
   3.   unsaturated
   4.   concentrated
5. Maximum amount of a solid solute that can be dissolved in a specified amount of a given liquid solvent does not depend upon _____
   1.   Temperature
   2.   Nature of solute
   3.   Nature of solvent
   4.   Pressure
6. Low concentration of oxygen in the blood and tissues of people living in high altitude is due to ____
   1.   low atmospheric pressure
   2.   low temperature
   3.   high atmospheric pressure
   4.   both low temperature and high atmospheric pressure
7. What type of deviation from Raoult's law is shown by a mixture of cyclohexane and ethanol ?
   1.   Positive
   2.   Negative
   3.   No deviation
   4.   It forms an ideal solution.
8. Colligative properties depend on _______
   1.   the nature of the solute particles dissolved in solution.
   2.   the nature of solvent particles
   3.   the physical properties of the solute particles dissolved in solution.
   4.   the number of solute particles.
9. An unripe mango placed in a concentrated salt solution to prepare pickle, shrivels because ___
   1.   it gains water due to osmosis
   2.   it loses water due to osmosis
   3.   it gains water due to reverse osmosis
   4.   it loses water due to reverse osmosis.
10. Considering the formation, breaking and strength of hydrogen bond, predict which of the following mixtures will show a positive deviation from Raoult’s law?
    1.   Methanol and acetone.
    2.   Chloroform and acetone.
    3.   Phenol and aniline
    4.   Nitric acid and water.
11. Which of the following aqueous solutions should have the highest boiling points?
    1.   1.0 M NaOH
    2.   1.0 M NH₄NO₃
    3.   1.0 M KNO₃
    4.   1.0 M Na₂SO₄
12. Calculate the molarity of a solution containing 5 g of NaOH in 450 mL solution.
    1.   1.9 mol L^-1
    2.   1.5 mol L^-1
    3.   0.278 mol L^-1
    4.   2.075 mol L^-1
13. At a given temperature, osmotic pressure of a concentrated solution of a substance ____
    1.   is lower than that of a dilute solution
    2.   is higher than that of a dilute solution
    3.   is same as that of a dilute solution
    4.   cannot be compared with osmotic pressure of dilute solution.
14. Which of the following statements is false?
    1.   Units of atmospheric pressure and osmotic pressure are the same
    2.   The value of molal depression constant depends on nature of solvent.
    3.   Relative lowering of vapour pressure, is a dimensionless quantity
    4.   In reverse osmosis, solvent molecules move through a semipermeable membrane from a region of lower concentration of solute to a region of higher concentration.
15. Isotonic solution must have the same _______
    1.   solute
    2.   elevation in boiling point
    3.   depression in freezing point
    4.   Both B & C.
16. If we place blood cells in a solution containing more than 0.9 % (m/v) NaCl solution :
    1.   Blood cells will shrink
    2.   pH of blood will change
    3.   Blood cells will swell
    4.   There is no change
17. In comparison to a 0.01 M solution of glucose, the depression in freezing point of a 0.01 M MgCl₂ solution is ____
    1.   about three times
    2.   the same
    3.   about twice
    4.   about six times
18. Which of the following is not a colligative property?
    1.   Depression in freezing point
    2.   Lowering of vapour pressure
    3.   Elevation in boiling point
    4.   Osmotic pressure.
19. Chloroform and acetone are mixed with each other. Will the mixture follow Raoult’s law?
    1.   It initially follows but after sometime does not follow
    2.   Yes
    3.   No
    4.   It initially does not follow but after sometime follow
20. Value of Henry’s constant K_H ____
    1.   increases with increase in temperature
    2.   decreases with increase in temperature
    3.   remains constant
    4.   first increases then decreases.
21. If two liquids A and B form minimum boiling azeotrope at same specific composition then _____
    1.   A-B interaction are weaker than those between A-A or B-B.
    2.   A-B interaction are stronger than those between A-A or B-B.
    3.   vapour pressure of solution increases because more number of molecules of liquids A and B can escape from the solution.
    4.   vapour pressure of solution decreases because less number of molecules of only one of the liquids escape from the solution.
22. KH value for Ar(g), CO₂(g), HCHO(g) and CH₄ (g) are 40.39, 1.67, 1.83 x 10_-5 and 0.413 respectively.
    Arrange these gases in the order of their increasing solubility.
    
    1.   HCHO < CH₄ < CO₂ < Ar
    2.   HCHO < CO₂ < CH₄ < Ar
    3.   Ar < CO₂ < CH₄ < HCHO
    4.   Ar < CH₄ < CO₂ < HCHO
23. The value of Henry’s constant K_H is ____________
    1.   greater for gases with higher solubility
    2.   constant for all gases
    3.   greater for gases with lower solubility
    4.   not related to the solubility of gases
24. 4 L of 0.02 M aqueous solution of NaCl was diluted by adding one litre of water. The molality of the resultant solution is ____
    1.   0.004
    2.   0.016
    3.   0.012
    4.   0.008
25. Out of 0.1M KCl and 0.1M Glucose
    1.   KCl has higher boiling point
    2.   Glucose has higher boiling point
    3.   Both have same boiling point
    4.   None of the above
26. Colligative properties are observed when ____
    1.   a non volatile solid is dissolved in a volatile liquid.
    2.   a non volatile liquid is dissolved in another volatile liquid.
    3.   a volatile liquid is dissolved in another volatile liquid.
    4.   Both A & B.
27. If N2 gas is bubbled through water at 293 K, how many millimoles of N2 gas would dissolve in 1 litre of water? Assume that N2 exerts a partial pressure of 0.987 bar. Given that Henry’s law constant for N2 at 293 K is 76.48 kbar.
    1.   0.717 mmol
    2.   1.4 mmol
    3.   8.4 mmol
    4.   815 mmol
28. Assertion (A): Molarity of a solution in liquid state changes with temperature
    Reason (R): The volume of a solution changes with change in temperature.
    
    1.   Both assertion (A) and reason (R) are correct statements, and reason (R) is the correct explanation of the assertion (A).
    2.   Both assertion (A) and reason (R) are correct statements, but reason (R) is not the correct explanation of the assertion (A).
    3.   Assertion (A) is correct, but reason (R) is incorrect statement.
    4.   Assertion (A) is incorrect, but reason (R) is correct statement.
29. Assertion (A): When a solution is separated from the pure solvent by a semipermeable membrane, the solvent molecules pass through it from pure solvent side to the solution side.
    Reason (R): Diffusion of solvent occurs from a region of high concentration solution to a region of low concentration solution.
    
    1.   Both assertion (A) and reason (R) are correct statements, and reason (R) is the correct explanation of the assertion (A).
    2.   Both assertion (A) and reason (R) are correct statements, but reason (R) is not the correct explanation of the assertion (A).
    3.   Assertion (A) is correct, but reason (R) is incorrect statement.
    4.   Assertion (A) is incorrect, but reason (R) is correct statement.
30. Assertion (A): Osmotic pressure is a colligative property.
    Reason (R): Osmotic pressure is directly proportional to molarity
    
    1.   Both assertion (A) and reason (R) are correct statements, and reason (R) is the correct explanation of the assertion (A).
    2.   Both assertion (A) and reason (R) are correct statements, but reason (R) is not the correct explanation of the assertion (A).
    3.   Assertion (A) is correct, but reason (R) is incorrect statement.
    4.   Assertion (A) is incorrect, but reason (R) is correct statement.

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