Chem 2 Chapter 13 Questions PDF

**1. Which of the following is always favorable for solution formation?**\ A) Exothermic enthalpy change and increasing entropy\ B) Endothermic enthalpy change and decreasing entropy\ C) Endothermic enthalpy change and increasing entropy\ D) Exothermic enthalpy change and decreasing entropy\ E) No e...

**1. Which of the following is always favorable for solution formation?**\ A) Exothermic enthalpy change and increasing entropy\ B) Endothermic enthalpy change and decreasing entropy\ C) Endothermic enthalpy change and increasing entropy\ D) Exothermic enthalpy change and decreasing entropy\ E) No enthalpy or entropy change **2. Which process in solution formation is always exothermic?**\ A) Breaking solute-solute interactions\ B) Breaking solvent-solvent interactions\ C) Forming solute-solvent interactions\ D) Increasing entropy\ E) Increasing temperature **3. If a solution formation process has a positive enthalpy change, under what condition can it still occur?**\ A) If the entropy change is negative\ B) If the entropy change is large and positive\ C) If the solute is nonpolar\ D) If the temperature is lowered\ E) If solvent-solvent interactions are weak **4. What is the primary factor determining whether a solute will dissolve in a solvent?**\ A) Molecular size\ B) Intermolecular forces\ C) Color of the solute\ D) Density of the solvent\ E) Presence of hydrogen bonding **5. According to the \'like dissolves like\' principle, which solvent would best dissolve NaCl?**\ A) Benzene\ B) Hexane\ C) Water\ D) Carbon tetrachloride\ E) Ethanol **6. What type of intermolecular force is dominant in nonpolar substances?**\ A) Hydrogen bonding\ B) Dipole-dipole interactions\ C) London dispersion forces\ D) Ion-dipole interactions\ E) Covalent bonding **7. Why does oil not dissolve in water?**\ A) Oil molecules are too large\ B) Water has stronger intermolecular forces than oil\ C) Oil molecules are nonpolar, and water is polar\ D) Water repels oil due to density differences\ E) Oil undergoes ionization in water **8. What is the role of dynamic equilibrium in the solution process?**\ A) It prevents solute from dissolving\ B) It ensures solubility remains constant at all conditions\ C) It maintains a balance between dissolution and crystallization\ D) It allows supersaturation to occur\ E) It determines whether a solute is polar or nonpolar **9. Which of the following represents the equilibrium expression for an ionic solid dissolving in water?**\ A) Kp = P/RT\ B) Ka = \[H+\]\[A-\] / \[HA\]\ C) Ksp = \[cation\]\^m \[anion\]\^n\ D) Kw = \[H+\]\[OH-\]\ E) ΔG = ΔH - TΔS **10. What does a high Ksp value indicate?**\ A) The solute has a low solubility\ B) The solute is nonpolar\ C) The solute has a high solubility\ D) The solvent is volatile\ E) The solute does not dissociate **11-50. Additional Questions:** **11. How does pressure affect the solubility of gases in liquids?**\ A) Increases solubility\ B) Decreases solubility\ C) Has no effect\ D) Depends only on the solvent\ E) Depends only on the gas **12. Why does increasing temperature usually increase the solubility of solids?**\ A) Increases kinetic energy of molecules\ B) Decreases entropy\ C) Weakens intermolecular forces\ D) Increases density of solvent\ E) Reduces vapor pressure **13. What is the main reason gases are less soluble at higher temperatures?**\ A) Gas molecules gain kinetic energy and escape the solvent\ B) The solvent molecules expand\ C) The intermolecular forces weaken\ D) The volume of gas decreases\ E) The gas molecules condense **14. Which factor does NOT affect solubility?**\ A) Temperature\ B) Pressure\ C) Surface area of solute\ D) Presence of a catalyst\ E) Nature of solvent **15. What effect does the common ion effect have on solubility?**\ A) Increases solubility\ B) Decreases solubility\ C) No effect\ D) Converts solute to gas\ E) Lowers vapor pressure **16. What happens when a solution becomes supersaturated?**\ A) Excess solute precipitates out\ B) The solution freezes\ C) The solvent evaporates completely\ D) The solute forms a gas\ E) The solvent becomes nonpolar **17. How does entropy affect solubility?**\ A) Higher entropy favors solubility\ B) Lower entropy favors solubility\ C) Entropy has no effect\ D) Solubility decreases with increasing entropy\ E) Entropy is only important for gases **18. Why does salt dissolve in water but not in oil?**\ A) Water is polar, oil is nonpolar\ B) Oil is denser than salt\ C) Water has larger molecules\ D) Oil molecules repel ions\ E) Salt undergoes a chemical reaction with water **19. What is the effect of adding a common ion to a saturated solution?**\ A) Increases solubility\ B) Decreases solubility\ C) No effect\ D) Changes the solute's molecular structure\ E) Causes gas formation **20. What is the primary reason ionic compounds dissolve in water?**\ A) London dispersion forces\ B) Dipole-dipole interactions\ C) Ion-dipole interactions\ D) Covalent bonding\ E) Hydrogen bonding **21. What happens to a solution when the temperature is lowered?**\ A) Solubility of gases increases\ B) Solubility of most solids increases\ C) Solubility of gases decreases\ D) The solution becomes unstable\ E) The solvent evaporates instantly **22. Which of the following colligative properties affects freezing point?**\ A) Vapor pressure lowering\ B) Boiling point elevation\ C) Freezing point depression\ D) Osmotic pressure\ E) Surface tension **23. How does increasing solute concentration affect the boiling point of a solution?**\ A) Lowers the boiling point\ B) Raises the boiling point\ C) No effect\ D) Increases vapor pressure\ E) Decreases intermolecular forces **24. What factor influences osmotic pressure?**\ A) Solvent polarity\ B) Temperature and solute concentration\ C) Atmospheric pressure\ D) Molar mass of solute\ E) Molecular size of solvent **25. What is the effect of increasing the number of solute particles on freezing point?**\ A) Raises freezing point\ B) Lowers freezing point\ C) No effect\ D) Increases intermolecular forces\ E) Decreases entropy **26. Which of the following statements best describes Raoult's Law?**\ A) Adding solute increases vapor pressure\ B) The vapor pressure of a solution is proportional to the mole fraction of solvent\ C) Increasing solute decreases boiling point\ D) Osmotic pressure is unrelated to solute concentration\ E) Freezing point remains constant in solutions **27. How does an increase in temperature affect vapor pressure?**\ A) Increases vapor pressure\ B) Decreases vapor pressure\ C) Has no effect\ D) Lowers boiling point\ E) Changes solute polarity **28. What type of solution contains the maximum amount of dissolved solute at equilibrium?**\ A) Saturated solution\ B) Unsaturated solution\ C) Supersaturated solution\ D) Diluted solution\ E) Concentrated solution **29. What is the key characteristic of a supersaturated solution?**\ A) Contains dissolved solute beyond equilibrium concentration\ B) Cannot hold more solute\ C) Solubility decreases with temperature increase\ D) Contains only a small amount of solute\ E) Must be ionic in nature **30. Which of the following solutions has the highest boiling point?**\ A) Pure water\ B) 1 M NaCl solution\ C) 1 M glucose solution\ D) 2 M NaCl solution\ E) 0.5 M sucrose solution **31. How does the addition of a non-volatile solute affect the vapor pressure of a solvent?**\ A) Increases vapor pressure\ B) Decreases vapor pressure\ C) Has no effect\ D) Increases temperature\ E) Enhances molecular motion **32. What happens when two solutions of different concentrations are separated by a semipermeable membrane?**\ A) Solute moves across the membrane\ B) Solvent moves from lower to higher concentration\ C) Solvent moves from higher to lower concentration\ D) Equilibrium is never reached\ E) Freezing point increases **33. What is the primary factor affecting colligative properties?**\ A) Identity of the solute\ B) Number of dissolved particles\ C) Molar mass of solvent\ D) Chemical properties of solute\ E) pH of the solution **34. Which of the following has the greatest effect on colligative properties?**\ A) 1 M NaCl\ B) 1 M glucose\ C) 1 M urea\ D) 1 M ethanol\ E) 1 M CH4 **35. Why does salt lower the freezing point of water?**\ A) It increases entropy\ B) It disrupts intermolecular forces\ C) It increases vapor pressure\ D) It reacts chemically with water\ E) It absorbs heat **36. Which statement best describes Henry's Law?**\ A) Gas solubility increases with increasing pressure\ B) Gas solubility increases with decreasing pressure\ C) Gas solubility is independent of pressure\ D) Gas dissolves better at higher temperatures\ E) Gas dissolves best in polar solvents **37. What is the primary driving force for osmosis?**\ A) Pressure difference\ B) Solvent concentration gradient\ C) Chemical reaction\ D) Solute concentration gradient\ E) Molecular weight **38. What effect does increasing atmospheric pressure have on the solubility of gases in liquids?**\ A) Increases solubility\ B) Decreases solubility\ C) No effect\ D) Increases temperature\ E) Enhances diffusion **39. Why does carbon dioxide escape from soda when opened?**\ A) A decrease in external pressure reduces gas solubility\ B) A decrease in temperature forces gas release\ C) A chemical reaction occurs\ D) Oxygen replaces carbon dioxide\ E) The pH of the soda changes **40. What is the effect of pressure on the boiling point of a liquid?**\ A) Higher pressure increases boiling point\ B) Higher pressure decreases boiling point\ C) Pressure has no effect\ D) Boiling point is only affected by solute\ E) Only gases are affected by pressure **41. Which of the following affects the solubility of ionic compounds in solution?**\ A) Common ion effect\ B) Lattice energy\ C) Solvent polarity\ D) Temperature\ E) All of the above **42. What is the primary cause of vapor pressure lowering in solutions?**\ A) Addition of a volatile solute\ B) Addition of a non-volatile solute\ C) Decrease in atmospheric pressure\ D) Increase in solvent polarity\ E) Increase in temperature **43. What happens when a non-volatile solute is added to a solvent?**\ A) Boiling point increases\ B) Freezing point increases\ C) Vapor pressure increases\ D) Solubility decreases\ E) Gas solubility increases **44. What determines the magnitude of colligative property changes?**\ A) Type of solute\ B) Concentration of solute particles\ C) Molar mass of solute\ D) Density of solvent\ E) Volume of solvent **45. What is the relationship between boiling point elevation and the number of dissolved solute particles?**\ A) Directly proportional\ B) Inversely proportional\ C) No relationship\ D) Exponentially related\ E) Independent of solute concentration **46. What is the effect of increasing solute concentration on osmotic pressure?**\ A) Increases osmotic pressure\ B) Decreases osmotic pressure\ C) No effect\ D) Depends on temperature\ E) Reduces solubility **47. How does molecular polarity affect solubility?**\ A) Polar solutes dissolve in polar solvents\ B) Nonpolar solutes dissolve in polar solvents\ C) Polarity has no effect\ D) Only ionic solutes dissolve in polar solvents\ E) Nonpolar solvents dissolve ionic solutes **48. What happens when a solution is at equilibrium?**\ A) Rate of dissolution equals rate of crystallization\ B) More solute dissolves over time\ C) The solution becomes supersaturated\ D) The solvent evaporates completely\ E) The solute precipitates out **49. How does increasing solute concentration affect freezing point depression?**\ A) Greater depression of freezing point\ B) No effect\ C) Increases freezing point\ D) Decreases boiling point\ E) Enhances vapor pressure **50. Which of the following best describes a colligative property?**\ A) Depends on the number of solute particles\ B) Depends on the identity of the solute\ C) Varies based on solvent reactivity\ D) Independent of solute concentration\ E) Affected by external pressure only **51. What is a colligative property?**\ A) A property that depends on the number of solute particles in a solution\ B) A property that depends on the chemical nature of the solute\ C) A property that determines the solubility of a substance\ D) A property that depends only on temperature\ E) A property that changes with molecular weight **52. Which of the following is NOT a colligative property?**\ A) Boiling point elevation\ B) Freezing point depression\ C) Vapor pressure lowering\ D) Osmotic pressure\ E) Surface tension **53. What does the Van't Hoff factor (i) represent?**\ A) The number of formula units in a solution\ B) The ratio of solute to solvent molecules\ C) The number of particles into which a solute dissociates in solution\ D) The boiling point of the solution\ E) The molecular weight of a solute **54. Which of the following compounds has a Van't Hoff factor (i) of 3?**\ A) NaCl\ B) KBr\ C) CaCl₂\ D) C₆H₁₂O₆\ E) CH₃COOH **55. What happens to the boiling point of a solution when a non-volatile solute is added?**\ A) It increases\ B) It decreases\ C) It remains the same\ D) It depends on the solute's polarity\ E) It depends on the solute's reactivity **56. Freezing point depression occurs because:**\ A) Solute particles disrupt the formation of the solid phase\ B) Solute particles increase kinetic energy\ C) Solvent molecules move faster\ D) The density of the solvent changes\ E) The vapor pressure of the solvent increases **57. Which solution has the highest boiling point?**\ A) 1 M NaCl\ B) 1 M C₆H₁₂O₆\ C) 1 M CaCl₂\ D) 1 M CH₃COOH\ E) 1 M KNO₃ **58. What is the key factor in determining the magnitude of a colligative property?**\ A) The number of solute particles in solution\ B) The identity of the solute\ C) The color of the solution\ D) The boiling point of the solvent\ E) The molecular weight of the solute **59. Which of the following best describes a solution?**\ A) A homogeneous mixture with completely dissolved solute particles\ B) A heterogeneous mixture with visible solute particles\ C) A suspension with large particles that settle over time\ D) A mixture that cannot be separated by filtration\ E) A system with intermediate-sized particles **60. What distinguishes a colloid from a true solution?**\ A) Colloids have larger particle sizes than solutions\ B) Colloids scatter light (Tyndall effect)\ C) Colloids cannot be separated by normal filtration\ D) Colloidal particles do not settle over time\ E) All of the above **61. Which of the following is an example of a colloid?**\ A) Saltwater\ B) Air\ C) Milk\ D) Sugar solution\ E) Copper sulfate solution **62. The Tyndall effect is observed in:**\ A) True solutions\ B) Colloids\ C) Suspensions\ D) Solvents\ E) Electrolyte solutions **63. What characteristic defines a hydrophilic colloid?**\ A) Strong attraction to water\ B) Repels water\ C) Does not interact with water\ D) Completely dissolves in water\ E) Only interacts with nonpolar solvents **64. How do hydrophilic colloids remain stable in water?**\ A) Hydration shell formation\ B) Electrostatic repulsion\ C) Emulsification\ D) Both A and B\ E) None of the above **65. What stabilizes hydrophobic colloids in water?**\ A) Surface charge addition\ B) Emulsification\ C) Hydration shell formation\ D) Both A and B\ E) None of the above **66. What role do surfactants play in emulsification?**\ A) Reduce surface tension\ B) Prevent aggregation of hydrophobic particles\ C) Form micelles around particles\ D) All of the above\ E) None of the above **67. Which of the following is an example of a hydrophobic colloid?**\ A) Starch\ B) Milk\ C) Paint\ D) Gelatin\ E) Protein solution **68. What happens when a colloidal solution is destabilized?**\ A) Particles aggregate and settle out\ B) Particles dissolve completely\ C) The solution remains unchanged\ D) The solution turns into a true solution\ E) The solute evaporates **69. What happens to osmotic pressure when solute concentration increases?**\ A) It increases\ B) It decreases\ C) It remains unchanged\ D) It depends on temperature\ E) It depends on solute identity **70. Which factor does NOT affect the magnitude of colligative properties?**\ A) The number of solute particles\ B) The solvent identity\ C) The Van't Hoff factor\ D) The temperature of the solution\ E) The mass of the solvent **71. Which type of solute has the greatest effect on colligative properties?**\ A) A strong electrolyte\ B) A weak electrolyte\ C) A non-electrolyte\ D) A gas\ E) A polymer **72. What does the addition of a solute do to the vapor pressure of a solvent?**\ A) Lowers it\ B) Raises it\ C) Has no effect\ D) Increases temperature\ E) Depends on solute identity **73. Why does an electrolyte have a greater effect on colligative properties than a nonelectrolyte?**\ A) It dissociates into multiple particles\ B) It is more soluble\ C) It has a higher molecular weight\ D) It increases entropy\ E) It reacts with the solvent **74. What is the key difference between a solution and a colloid?**\ A) Colloids scatter light\ B) Colloids settle over time\ C) Solutions have larger particles\ D) Colloids are homogeneous mixtures\ E) Solutions are always opaque **75. Which of the following is NOT an example of a colloid?**\ A) Blood\ B) Gelatin\ C) Air\ D) Fog\ E) Paint **76. What property allows colloids to remain dispersed in a solvent?**\ A) Electrostatic repulsion\ B) Large particle size\ C) High density\ D) Chemical reactivity\ E) High surface tension **77. How does an emulsifier stabilize a colloid?**\ A) By preventing aggregation\ B) By reducing solubility\ C) By increasing particle size\ D) By decreasing temperature\ E) By neutralizing charges **78. Which type of colloid consists of liquid droplets dispersed in another liquid?**\ A) Emulsion\ B) Aerosol\ C) Gel\ D) Foam\ E) Suspension **79. What is the main reason hydrophobic colloids need stabilization?**\ A) They tend to aggregate in water\ B) They dissolve easily\ C) They form true solutions\ D) They repel solvents\ E) They are highly volatile **80. What is the purpose of the Van't Hoff factor in colligative property calculations?**\ A) To account for solute dissociation\ B) To determine solubility\ C) To measure boiling point\ D) To adjust pH\ E) To increase solute reactivity