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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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