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Key Concepts PowerPoint

Chapter 11
Solutions and Their Properties

  
11-00-02UN
Title
 Solutions and intermolecular forces
Caption
 Solutions form when solvent-solvent, solute-solute, and solute-solvent forces are similar.
Notes
 Solutions and intermolecular forces
Keywords
 solution, intermolecular forces
11-01
Title
 Dissolution of NaCl in water
Caption
 Figure 11.1 Dissolution of NaCl crystals in water. Water molecules surround an accessible edge or corner ion in a crystal and collide with it until the ion breaks free. Additional water molecules then surround the ion and stabilize it by means of ion-dipole attractions.
Notes
 Dissolution of NaCl in water
Keywords
 ion-dipole, dissolution
11-02
Title
 Entropies of solutions
Caption
 Figure 11.2 Entropies of solution are usually positive because molecular randomness usually increases when (a) a solid dissolves in a liquid or (b) one liquid dissolves in another.
Notes
 Entropies of solution
Keywords
 entropy, randomness, solution
11-04
Title
 Enthalpy of solution
Caption
 Figure 11.4 The value of DHsoln is the sum of three terms: solvent-solvent, solute-solute, and solvent-solute. It can be either (a) negative or (b) positive.
Notes
 Enthalpy of solution measures how much energy is either absorbed or released when a solution is prepared.
Keywords
 enthalpy, solution
11-04-01UN
Title
 Pentane and 1-butanol
Caption
 Worked Example 11.1 From the structures provided, which compound would you expect to be more soluble in water? Explain.
Notes
 Pentane and 1-butanol, structure-property relationship
Keywords
 pentane, 1-butanol, solubility
11-04-03UN
Title
 Ethylene glycol
Caption
 Ethylene glycol is the colorless liquid used in automobile antifreeze.
Notes
 Ethylene glycol structure, used in conjunction with Worked Example 11.5
Keywords
 ethylene glycol
11-06
Title
 Solubility and temperature
Caption
 Figure 11.6 Solubilities of some common solids in water as a function of temperature. Most substances become more soluble as temperature rises, although the exact relationship is often complex and nonlinear.
Notes
 Temperature dependence on solubility of common solids in water
Keywords
 solubility, termperature, solids
11-07
Title
 Solubility and temperature
Caption
 Figure 11.7 Solubilities of some gases in water as a function of temperature. Most gases become less soluble in water as the temperature rises. The concentration units are millimoles per liter (mmol/L) at a gas pressure of 1 atm.
Notes
 Temperature dependence of the solubility of some gases in water
Keywords
 solubility, temperature, gases
11-08
Title
 Henry's Law
Caption
 Figure 11.8 A molecular view of Henry’s law. (a) At a given pressure, an equilibrium exists in which equal numbers of gas particles enter and leave the solution. (b) When pressure is increased by pushing on the piston, more gas particles are temporarily forced into solution than are able to leave, so solubility increases until a new equilibrium is reached (c).
Notes
 Henry's law, relating pressure and solubility of a gas
Keywords
 Henry's law, pressure, solubility
11-08-02UN
Title
 Colligative properties
Caption
 Colligative properties—properties that depend on the amount of a dissolved solute but not on its chemical identity. For strong electrolytes, the amount of dissolved solute translates into the amount of dissolved particles.
Notes
 Colligative properties
Keywords
 colligative properties
11-09
Title
 Vapor-pressure lowering of solutions
Caption
 Figure 11.9 The equilibrium vapor pressure of a solution with (a) a nonvolatile solute is always lower than that of (b) the pure solvent by an amount that depends on the mole fraction of the solvent.
Notes
 Raoult's law relates the vapor pressure of a solution to the vapor pressure of the pure solvent times the mole fraction of the solvent in the solution.
Keywords
 vapor-pressure lowering, mole fraction, Raoult's law
11-10
Title
 Entropy and vapor pressure
Caption
 Figure 11.10 The lower vapor pressure of a solution relative to that of a pure solvent is due to the difference in their entropies of vaporization, DSvap. Because the entropy of the solution is higher to begin with, DSvap is smaller for the solvent in the solution than for the pure solvent. As a result, vaporization of the solution is less favored (less negative DGvap), and the vapor pressure of the solution is lower.
Notes
 Entropies of vaporization of pure solvent versus solution
Keywords
 vapor pressure, entropy of vaporization
11-10-01UN
Title
 Key Concept Problem 11.15
Caption
 Vapor pressure curve.
Notes
 Vapor pressure curve for Problem 11.15
Keywords
 key concept, vapor pressure
11-11
Title
 Vapor pressure of a solution
Caption
 Figure 11.11 The vapor pressure of a solution of the two volatile liquids benzene and toluene at 25°C is the sum of the two individual vapor pressures, each calculated by Raoult’s law.
Notes
 Vapor pressure of a solution comprised of two volatile liquids
Keywords
 vapor pressure, Raoult's law
11-11-01UN
Title
 Key Concept Problem 11.10
Caption
 Vapor pressure curves for two pure liquids and a mixture of the two.
Notes
 Key concept problem 11.10
Keywords
 vapor pressure, solutions
11-11-02UN
Title
 Key Concept Problem 11.17
Caption
 Vapor pressure curves for a pure liquid and a mixture of the liquid with another volatile liquid.
Notes
 Key concept problem 11.17
Keywords
 vapor pressure, solutions
11-12
Title
 Phase diagrams
Caption
 Figure 11.12 Phase diagrams for a pure solvent (red line) and a solution (green line). Because the vapor pressure of the solution is lower than that of the pure solvent at a given temperature, the temperature at which the vapor pressure reaches atmospheric pressure is higher for the solution than for the solvent. Thus, the boiling point of the solution is higher by an amount DTb. Furthermore, because the liquid/vapor phase transition line is lower for the solution than for the solvent, the triple-point temperature Tt is lower and the solid/liquid phase transition line is shifted to a lower temperature. As a result, the freezing point of the solution is lower than that of the pure solvent by an amount DTf.
Notes
 Phase diagrams for a pure solvent and a solution
Keywords
 phase diagram
11-13
Title
 Boiling point elevation
Caption
 Figure 11.13 The higher boiling point of a solution relative to that of a pure solvent is due to a difference in their entropies of vaporization, DSvap. Because the solvent in the solution has a higher entropy to begin with, DSvap is smaller for the solution than for the pure solvent. As a result, the boiling point of the solution Tb is higher than that of the pure solvent.
Notes
 Boiling point elevation relative to ethalpy and entropy of vaporization
Keywords
 boiling point elevation, colligative properties
11-14
Title
 Freezing point depression
Caption
 Figure 11.14 The lower freezing point of a solution relative to that of a pure solvent is due to a difference in their entropies of fusion, DSfusion. Because the solvent in the solution has a higher entropy level to begin with, DSfusion is larger for the solution than for the pure solvent. As a result, the freezing point of the solution Tf is lower than that of the pure solvent.
Notes
 Freezing point depression relative to enthalpy and entropy of fusion
Keywords
 freezing point depression, colligative
11-14-01UN
Title
 Key Concept Problem 11.22
Caption
 Abbreviated phase diagram for pure chloroform and a solution of a nonvolatile solute in chloroform.
Notes
 Key concept problem 11.22
Keywords
 key concept, boiling point elevation, molality
11-15
Title
 Osmosis
Caption
 Figure 11.15 The phenomenon of osmosis. A solution inside the bulb is separated from pure solvent in the container by a semipermeable membrane. Net passage of solvent from the container through the membrane occurs, and the liquid in the tube rises until an equilibrium is reached. At equilibrium, the osmotic pressure exerted by the column of liquid in the tube is sufficient to prevent further net passage of solvent.
Notes
 Osmosis and osmotic pressure
Keywords
 osmosis, osmotic pressure
11-16
Title
 Reverse osmosis
Caption
 Figure 11.16 The desalination of seawater by reverse osmosis. By applying a pressure on the seawater that is greater than osmotic pressure, water is forced through the osmotic membrane from the seawater side to the pure water side.
Notes
 Application of reverse osmosis to water purification
Keywords
 reverse osmosis
11-17
Title
 Fractional distillation
Caption
 Figure 11.17 Vapor-pressure curves for pure benzene (blue), pure toluene (red), and a 1:1 mixture of the two (green). The mixture boils at 92.2°C (365.3 K) at atmospheric pressure.
Notes
 Fractional distillation due to differences in liquid vapor pressures
Keywords
 fractional distillation, vapor pressure
11-18
Title
 Fractional distillation
Caption
 Figure 11.18 A phase diagram of temperature versus composition (mole fraction) for a mixture of benzene and toluene. Liquid composition is given by the lower curve, and vapor composition is given by the top curve. The thin region between curves represents an equilibrium between phases. Liquid and vapor compositions at a given temperature are connected by a horizontal tie line, as explained in the text.
Notes
 Fractional distillation and mole fraction
Keywords
 fractional distillation, mole fraction
11-19
Title
 Fractional distillation column
Caption
 Figure 11.19 A simple fractional distillation column used in a chemistry laboratory. The vapors from a boiling mixture of liquids rise inside the column, where they condense on contact with the cool column walls, drip back, and are reboiled by contact with more hot vapor. Numerous boil/condense cycles occur before vapors finally pass out the top of the column, reach the water-cooled condenser, and drip into the receiver.
Notes
 Fractional distillation column
Keywords
 fractional distillation
11-19-01UN
Title
 Key Concept Problem 11.27
Caption
 Phase diagram of temperature versus composition for a mixture.
Notes
 Key concept problem 11.27
Keywords
 key concept, phase diagram, distillation
11-19-020UN
Title
 Key Concept Summary
Caption
 Solutions and their properties key concept summary.
Notes
 Key concept summary
Keywords
 key concept, summary
11-19-03UN
Title
 Key Concept Problem 11.29
Caption
 Partial phase diagram for pure ether and a solution of a nonvolatile solute in ether.
Notes
 Key concept problem 11.29
Keywords
 key concept, boiling point elevation
11-19-04UN
Title
 Key Concept Problem 11.30
Caption
 Rank the drawn situations according to increasing entropy.
Notes
 Key concept problem 11.30
Keywords
 key concept, entropy
11-19-05UN
Title
 Key Concept Problem 11.31
Caption
 Partial phase diagram for a pure solvent and a solution of the solvent with another volatile liquid.
Notes
 Key concept problem 11.31
Keywords
 key concept, vapor pressure lowering
11-19-06UN
Title
 Key Concept Problem 11.32
Caption
 Two liquids separated by a semipermeable membrane.
Notes
 Key concept problem 11.32
Keywords
 key concept, osmosis
11-19-09UN
Title
 Key Concept Problem 11.35
Caption
 Phase diagram for a mixture of two volatile liquids, octane and decane.
Notes
 Key concept problem 11.35
Keywords
 key concept, distillation
11-TB01
Title
 Table 11.1 Some Different Kinds of Solutions
Caption
Notes
Keywords
11-TB02
Title
 Table 11.2 Some Enthalpies and Entropies of Solution in Water at 25°C
Caption
Notes
Keywords
11-TB03
Title
 Table 11.3 A Comparison of Various Concentration Units
Caption
Notes
Keywords
11-TB04
Title
 Table 11.4 Molal Boiling-Point-Elevation Constants and Molal Freezing-Point-Depression Constants for Some Common Substances
Caption
Notes
Keywords
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