Colligative Properties and Solutions Multiple Choice Questions

Government of Karnataka 1 Multiple Choice Questions (MCQs) 1. 2. 3. 4. 5. 6. 7. Which of the following is dependent on temperature? a) Molarity b) Mole fraction c) Weight percentage d) Molality Which of the following compounds can be used as antifreeze in automobile radiators? a) Methyl alcohol b) Nitrophenol c) Glycol d) Ethyl alcohol The dissolution of gas is in a liquid is governed a) Raoult’s law b) Henry's law c) Dalton’s law of pressure d) van’t Hoff factor The mole fraction of the solute in one molal aqueous solution is a) 0.009 b) 0.018 c) 0.027 d) 0.036 Out of following which one is not an example of a solution. a) Air b) Brass c) amalgam d) benzene in water If one mole of a substance is present in one kg of solvent, then a) It shows molar concentration b) It shows molal concentration c) It shows normality d) It shows strength g/g Statement I: On adding NaCl to water its vapour pressure increases Statement II: Addition of non-volatile solute increases the vapour pressure. 8. 9. 10. a) Both statement I and II are correct b) Both statement I and statement II are wrong c) Statement I is correct and statement II is incorrect d) Statement I is incorrect and statement II is correct PA and PB are the vapour pressures of pure liquid components, A and B, respectively of an ideal binary solution. If XA represents the mole fraction of component A, the total pressure of the solution will be a) PA+ XA(PB–PA) b) PA+ XA(PA–PB) c) PB+XA(PB–PA) d) PB+XA(PA–PB) The vapour pressure of two liquids P and Q are 80 and 60 torr, respectively. The total vapour pressure of solution obtained by mixing 3 mole of P and 2 mol of Q would be a) 72 torr b) 140 torr c) 68 torr d) 20 torr The mixture which shows positive deviation from Raoult's law is a) ethanol + acetone b) benzene + toluene c) acetone + chloroform d) chloroethane + bromoethane. 11. 12. 13. 14. 15. 16. 17. 18. 19. The mixture that forms maximum boiling azeotrope is a) heptane + octane b) water nitric acid c) ethanol + water d) acetone + carbon disulphide. Which of the following statements is correct regarding a solution of two components A and B exhibiting positive deviation from ideal behaviour? a) Intermolecular attractive forces between A-A and B-B are stronger than those between A-B. b) ΔVmixH = 0 at constant T and P. c) ΔVmixV = 0 at constant T and P. d) Intermolecular attractive forces between A-A and B-B are equal to those between A-B. Which of the following statements about the composition of the vapour over an ideal 1: 1 molar mixture of benzene and toluene is correct? Assume that the temperature is constant at 25°C. (Given, vapour pressure data at 25°C, benzene 12.8 kPa, toluene = 3.85 kPa). a) The vapour will contain equal amounts of benzene and toluene. b) Not enough information is given to make a prediction. c) The vapour will contain a higher percentage of benzene. d) The vapour will contain a higher percentage of toluene. A solution containing components A and B follows Raoult's law. a) A-B attraction force is greater than A - A and B-B b) A-B attraction force is less than A - A and B – B c) A-B attraction force remains same as A - A and B-B d) volume of solution is different from sum of volume of solute and solvent. All form ideal solution except a) C6H6 and C6H5,CH3 b) C2H6 and C₂H5I c) C6H5Cl and C6H5Br d) C2H5I and C₂H5OH An ideal solution is formed when its components a) have no volume change on mixing. b) have no enthalpy change on mixing. c) have both the above characteristics. d) have high solubility. If molality of the dilute solution is doubled, the value of molal depression constant (Kf) will be a) halved b) tripled c) unchanged d) doubled. During osmosis, flow of water through a semipermeable membrane is a) from solution having lower concentration only b) from solution having higher concentration only c) from both sides of semipermeable membrane with equal flow rates d) from both sides of semipermeable membrane with unequal flow rates. Pure water can be obtained from sea water by a) centrifugation b) plasmolysis c) reverse osmosis d) sedimentation.