Tiêu đề 16. Solutions.pdf ✅

SOLUTIONS 16 FACT/DEFINITION TYPE QUESTIONS 1. “The importance of many pure substance in life depends on their composition.” Which of the following statement justify the above fact? (a) 1 ppm of fluoride ions in water prevents tooth decay. (b) 1.5 ppm of fluoride ions causes tooth decay. (c) Concentration above 1.5 ppm can be poisonous. (d) All of the above. 2. Which of the following fluoride is used as rat poison? (a) CaF2 (b) KF (c) NaF (d) MgF2 3. Most of the processes in our body occur in (a) solid solution (b) liquid solution (c) gaseous solution (d) colloidal solution 4. The term homogenous mixtures signifies that (a) its composition is uniform throughout the mixture. (b) its properties are uniform throughout the mixture. (c) both composition and properties are uniform throughout the mixture. (d) neither composition nor properties are uniform throughout the mixture. 5. Which of the following mixture is(are) called solution? (i) water + ammonia (ii) water + acetone (iii) acetone + alcohol (iv) hexane + water (a) (i), (ii) and (iii) (b) (i), (iii) and (iv) (c) (i) and (iv) (d) (ii) and (iii) 6. Which of the following is a quantitative description of the solution? (a) Dilute (b) Concentrated (c) Saturated (d) Molar 7. When a solute is present in trace quantities the following expression is used (a) Gram per million (b) Milligram percent (c) Microgram percent (d) Parts per million 8. Molarity of liquid HCl will be, if density of solution is 1.17 gm/cc (a) 36.5 (b) 32.05 (c) 18.25 (d) 42.10 9. 1 M, 2.5 litre NaOH solution is mixed with another 0.5 M, 3 litre NaOH solution. Then find out the molarity of resultant solution (a) 0.80 M (b) 1.0 M (c) 0.73 M (d) 0.50 M 10. An X molal solution of a compound in benzene has mole fraction of solute equal to 0.2. The value of X is (a) 14 (b) 3.2 (c) 1.4 (d) 2 11. The molarity of the solution containing 7.1 g of Na2 SO4 in 100 ml of aqueous solution is (a) 2 M (b) 0.5 M (c) 1 M (d) 0.05 M 12. The vapour pressure of pure benzene at 25°C is 640 mm Hg and that of solution of solute A is 630 mm Hg. The molality of solution is (a) 0.2 m (b) 0.4 m (c) 0.5 m (d) 0.1 m 13. 4.0 g of NaOH is dissolved in 100 ml solution. The normality of the solution is (a) 0.1 N (b) 0.5 N (c) 4.0 N (d) 1.0 N 14. The molarity of pure water is (a) 50 M (b) 18 M (c) 55.6 M (d) 100 M 15. An aqueous solution of glucose is 10% in strength. The volume in which 1 g mole of it is dissolved, will be (a) 9 litre (b) 1.8 litre (c) 8 litre (d) 0.9 litre 16. 10 g of NaCl is dissolved in 10 g 6 of the solution. Its concentration is (a) 100 ppm (b) 0.1 ppm (c) 1 ppm (d) 10 ppm 17. On adding a solute to a solvent having vapour pressure 0.80 atm, vapour pressure reduces to 0.60 atm. Mole fraction of solute is (a) 0.25 (b) 0.75 (c) 0.50 (d) 0.33
256 SOLUTIONS 18. 2.5 litres of NaCl solution contain 5 moles of the solute. What is the molarity? (a) 5 molar (b) 2 molar (c) 2.5 molar (d) 12.5 molar 19. The mole fraction of the solute in one molal aqueous solution i (a) 0.009 (b) 0.018 (c) 0.027 (d) 0.036 20. 5 ml of N HCl, 20 ml of N/2 H2 SO4 and 30 ml of N/3 HNO3 are mixed together and volume made to one litre. The normality of the resulting solution is (a) N 5 (b) N 10 (c) N 20 (d) N 40 21. 25ml of a solution of barium hydroxide on titration with a 0.1 molar solution of hydrochloric acid gave a titre value of 35 ml. The molarity of barium hydroxide solution was (a) 0.07 (b) 0.14 (c) 0.28 (d) 0.35 22. Mole fraction of the solute in a 1.00 molal aqueous solution is (a) 0.1770 (b) 0.0177 (c) 0.0344 (d) 1.7700 23. What is the normality of a 1 M solution of H3 PO4 ? (a) 0.5 N (b) 1.0 N (c) 2.0 N (d) 3.0 N 24. The volume of 4 N HCl and 10 N HCl required to make 1 litre of 6 N HCl are (a) 0.75 litre of 10 N HCl and 0.25 litre of 4 N HCl (b) 0.50 litre of 4 N HCl and 0.50 litre of 10 N HCl (c) 0.67 litre of 4 N HCl and 0.33 litre of 10 N HCl (d) 0.80 litre of 4 N HCl and 0.20 litre of 10 N HCl 25. Molarity of H2 SO4 is 18 M. Its density is 1.8 g/ml. Hence molality is (a) 36 (b) 200 (c) 500 (d) 18 26. 200 ml of water is added to 500 ml of 0.2 M solution. What is the molarity of this diluted solution ? (a) 0.5010 M (b) 0.2897 M (c) 0.7093 M (d) 0.1428 M 27. How many grams of concentrated nitric acid solution should be used to prepare 250 mL of 2.0M HNO3 ? The concentrated acid is 70% HNO3 (a) 90.0 g conc. HNO3 (b) 70.0 g conc. HNO3 (c) 54.0 g conc. HNO3 (d) 45.0 g conc. HNO3 28. For preparing 0.1 N solution of a compound from its impure sample of which the percentage purity is known, the weight of the substance required will be (a) Less than the theoretical weight (b) More than the theoretical weight (c) Same as the theoretical weight (d) None of these 29. If 10 N 50 ml H2 SO4 , 3 N 30 ml HNO3 , 2 N 10 ml HCl is mixed and solution is made to 1L. Then normality of resultant solution is (a) 20 N (b) 40 N (c) 50 N (d) N 30. A solution made by dissolving 40 g NaOH in 1000 g of water is (a) 1 molar (b) 1 normal (c) 1 molal (d) None of these 31. Which of the following concentration terms is/are independent of temperature? (a) Molality only (b) Molality and mole fraction (c) Molarity and mole fraction (d) Molality and normality 32. A solution is prepared by dissolving 10 g NaOH in 1250 mL of a solvent of density 0.8 mL/g. The molality of the solution in mol kg–1 is (a) 0.25 (b) 0.2 (c) 0.008 (d) 0.0064 33. Which of the following units is useful in relating concentration of solution with its vapour pressure? (a) mole fraction (b) parts per million (c) mass percentage (d) molality 34. For mixture containing “four” components which of the following is correct in term of mole fraction? (a) x1 + x2 + x3 + x4 z (b) 3 3 1 2 3 n x n n n (c 1 1 1 1 2 3 4 n n x n nnn n 6 (d) n1 + n2 + n3 + n4 = 1 35. Which of the following concentration unit is independent of temperature ? (a) Normality (b) Molarity (c) Formality (d) Molality 36. Which of the following factor do not affect solubility of solid solute in liquid ? (a) Temperature (b) Pressure (c) Nature of solute (d) All of these 37. When a solid solute is added to the solvent, some solute dissolves and its concentration increases in solution. This process is known as ______. Some solute particles in solution collide with the solid solute particles and get separated out of solution. This process is known as ______. (a) Crystallization, dissolution. (b) Dissolution, saturation. (c) Saturation, crystallization. (d) Dissolution, crystallization. EduHulk SOLUTIONS
SOLUTIONS 257 38. At the state of dynamic equilibrium, for solute + solvent solution. (a) Rate of dissolution = Rate of unsaturation. (b) Rate of dissolution = Rate of unsaturation. (c) Rate of dissolution = Rate of saturation (d) Rate of crystallization = Rate of saturation. 39. Which of the following statements is incorrect? (a) A solution in which no more solute can be dissolved at the same temperature and pressure is called a saturated solution. (b) An unsaturated solution is one in which more solute can be dissolved at the same temperature. (c) The solution which is in dynamic equilibrium with undissolved solute is the saturated solution. (d) The minimum amount of solute dissolved in a given amount of solvent is its solubility. 40. 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 ? (a) Sugar crystals in cold water. (b) Sugar crystals in hot water. (c) Powdered sugar in cold water. (d) Powdered sugar in hot water. 41. The solubility of a solid in a liquid is significantly affected by temperature changes. Solute + Solvent YZZ ZZX Solution. The system being in a dynamic equilibrium must follow Le-chatelier’s principle. Considering the Le-chatelier’s principle which of the following is correct? (a) '+sol > 0; solubility n ; temperaturep (b) '+sol < 0; solubility p ; temperaturen (c) '+sol > 0; solubility p ; temperaturen (d) '+sol < 0; solubility n ; temperaturen 42. Piston (a) (b) W1 W1 W2 W3 On the basis of the figure given above which of the following is not true? (a) In figure (a) assuming the state of dynamic equilibrium rate of gaseous particles entering and leaving the solution phase is same. (b) In figure (b) on compressing the gas number of gaseous particles per unit volume over the solution increases. (c) Rate at which gaseous particles are striking the solution to enter it, decreases. (d) Rate at which gaseous particles are striking the solution to enter it, increases. 43. The statement “If 0.003 moles of a gas are dissolved in 900 g of water under a pressure of 1 atmosphere, 0.006 moles will be dissolved under a pressure of 2 atmospheres”, illustrates (a) Dalton’s law of partial pressure (b) Graham’s law (c) Raoult’s law (d) Henry’s law 44. According to Henry’s law, the amount of gas that will dissolve in blood plasma or any other liquid is determined by which of these factor? (a) Solubility of the gas in the liquid. (b) The total pressure of the gas mixture . (c) pH of the liquid. (d) The osmotic pressure of the gas mixture. 45. Henry’s law constant of oxygen is 1.4 × 10–3 mol. lit–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) 1.4 g (b) 3.2 g (c) 22.4 mg (d) 2.24 mg 46. At equillibrium the rate of dissolution of a solid solute in a volatile liquid solvent is ______. (a) less than the rate of crystallisation. (b) greater than the rate of crystallisation. (c) equal to the rate of crystallisation. (d) zero 47. 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 ______. (a) saturated (b) supersaturated (c) unsaturated (d) concentrated 48. Maximum amount of a solid solute that can be dissolved in a specified amount of a given liquid solvent does not depend upon __________. (a) Temperature (b) Nature of solute (c) Pressure (d) Nature of solvent 49. Low concentration of oxygen in the blood and tissues of people living at high altitude is due to _________. (a) low temperature (b) low atmospheric pressure (c) high atmospheric pressure (d) both low temperature and high atmospheric pressure 50. Value of Henry's constant KH _______. (a) increases with increase in temperature. (b) decreases with increase in temperature. (c) remains constant. (d) first increases then decreases. 51. The value of Henry's constant KH is _______. (a) greater for gases with higher solubility. (b) greater for gases with lower solubility. (c) constant for all gases. (d) not related to the solubility of gases. EduHulk SOLUTIONS
258 SOLUTIONS 52. Which of the followingfactor(s) affect the solubility of a gaseous solute in the fixed volume of liquid solvent ? (i) Nature of solute (ii) Temperature (iii) Pressure (a) (i) and (iii) at constant T (b) (i) and (ii) at constant P (c) (ii) and (iii) only (d) (iii) only 53. Which of the following graph is a correct representation of Henry’s law? (a) Mole fraction of in solution gas Partial pressure of gas (b) Partial pressure of gas Mole fraction of in solution gas (c) Mole fraction of in solution gas Partial pressure of gas (d) Mole fraction of in solution gas Partial pressure of gas 54. Which is an application of Henry’s law? (a) Spray paint (b) Bottled water (c) Filling up atire (d) Soft drinks (soda) 55. Scuba divers may experience a condition called ______. To avoids this, the tanks used by scuba divers are filled with air diluted with _____ . (a) Migrains, Hydrogen (b) Cramps, Nitrogen (c) Nausea, Oxygen (d) Bends, Helium 56. People living at high attitudes often reported with a problem of feeling weak and inability to think clearly. The reason for this is. (a) at high altitudes the partial pressure of oxygen is less than at the ground level. (b) at high altitudes the partial pressure of oxygen is more than at the ground level. (c) at high altitudes the partial pressure of oxygen is equal to at the ground level. (d) None of these. 57. ____ a contemporary of Henry concluded independently that solubility of a gas in a liquid solution is a function of ____ of the gas. (a) Mosley, temperature (b) Dalton, temperature (c) Dalton, partial pressure (d) Mosley, partial pressure 58. Raoult’s law becomes a special case of Henry’s law when (a) H 1 K p = ° (b) H 1 K p > ° (c) H 1 K p < ° (d) H 1 K p 3 ° 59. Iodine and sulphur dissolve in (a) water (b) benzene (c) carbon disulphide (d) ethanol 60. The liquids at a given temperature vapourise and under equilibrium conditions the pressure exerted by the vapours of the liquid over the liquid phase is called (a) osmotic pressure (b) atmospheric pressure (c) hydrostatic pressure (d) vapour pressure 61. The vapour pressure of the solution at a given temperature is found to be ............... than the vapour pressure of the pure solvent at the same temperature. (a) higher (b) lower (c) equal (d) can't calculate 62. The decrease in the vapour pressure of solvent depends on the (a) quantity of non-volatile solute present in the solution (b) nature of non-volatile solute present in the solution (c) molar mass of non-volatile solute present in the solution (d) physical state of non-volatile solute present in the solution 63. A plot of p1 or p2 vs the mole fractions x1 and x2 is given as. Vapour pressure Mole fraction x2 x x 1 = 0 1 = 1 x2 x = 1 2 = 0 I II III p p p Total 1 2 = + p 2 p 1 p 1 ° p2 ° In this figure, lines I and II pass through the point for which. (a) x 1 z 1; x 2 = 1 (b) x 1 = x 2 z 1 (c) x 1 = 1; x 2 z d) x 1 = x 2 = 1 64. 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 mole of Q would be (a) 72 torr (b) 140 torr (c) 68 torr (d) 20 torr 65. 18 g of glucose (C6H12O6 ) is added to 178.2 g of water. The vapour pressure of water for this aqueous solution is (a) 76.00 torr (b) 752.40 torr (c) 759.00 torr (d) 7.60 torr 66. PA and PB are the vapour pressure 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 ) EduHulk SOLUTIONS