1. Chemistry of Solutions
A world without solutions would be just filled with …

2. Common Solutions Chemical solutions encountered in everyday life:
air coffee
tap water gasoline
shampoo cough syrup
orange soda Gatorade
. . . the components of a mixture are uniformly intermingled (the mixture is homogeneous).

3. Solution - Colloid - Suspension
Transparent Tyndall Effect Opaque
Never Settles Never Settles Eventually Settles

4. Solute - Solvent Solute Solvent Solution Example Gas Gas Gas Air
Liquid Liquid Liquid Vodka in Water
Solid Solid Solid Brass, Steel
Gas Liquid Liquid Carbonated water
Gas Solid Solid H in Platinum
Solid Liquid Liquid Salt Water
Liquid Solid Solid Hg in Silver

5. Solute vs Solvent The solvent is present in greater amount
The solvent retains its phase
The solute is present in lesser amount

6. Aqueous Solutions
Aqueous solutions are solutions in which water is the solvent.
Aqueous solutions are the most common type of solution.

7. Creating a Solution
When solid sodium chloride dissolves, the ions are dispersed randomly throughout the solution. In due time, the ions are evenly dispersed.

8. Break Lattice Energy
Ion-Dipole Attraction
Break
H-bonds

9. aka Heat of Solution or Enthalpy of Dissolution
Enthalpy of Solution
aka Heat of Solution or Enthalpy of Dissolution
Some compounds release energy when they dissolve in water. (Exothermic)
NaOH = kJ/mol
Some compounds absorb energy when they dissolve in water. (Endothermic)
KClO3 = kJ/mol

10. Oil and Water

11. Solubility The general rule for solubility is: “Like dissolves like.”
Polar water molecules can dissolve other polar molecules such as alcohol and, also, ionic substances such as NaCl.
Nonpolar molecules can dissolve other nonpolar molecules but not polar or ionic substances. Gasoline can dissolve grease.

12. Ethylene Glycol (Polar) vs. Octane (Nonpolar)
Molecular “Snobbery”
Ethylene Glycol (Polar) vs. Octane (Nonpolar)

13. Intermolecular Forces

14. Dipole-Induced Dipole
glucose in water
NaCl in water
Ion-Dipole
Dipole-Dipole
Hydrogen Bonding
oxygen gas in water
Dipole-Induced Dipole

15. Strength of Intermolecular Forces

16. Structure & Solubility
Hydrophobic -- water-fearing.
Hydrophilic -- water-loving.

17. Chemistry of Soap
Soap molecules can bind with oil or nonpolar molecules on one end, and bind with water on the other end.

18. How much can dissolve?
Unsaturated - when a solution has not reached its limit of solubility.
Saturated - when a solution contains as much solute as will dissolve at that temperature.
Supersaturated - when a solution has more of the solute dissolved than it normally would – a unstable (tenuous) condition.

19. Solubility Curves

20. Solubility of a Gas in Water

21. How can we get more gas to dissolve in water?

22. Dissociation
When ionic compounds dissolve in water the anions and cations are separated
KCl(aq)  K+ (aq) + Cl- (aq) K+
Cl- K Cl
K2SO4(aq)  2 K+ (aq) + SO42-(aq) K+
SO42- K
SO4 4

23. pure H2O, sugar solution, glycerol
Electrolytes
Strong - conduct current efficiently - many ions in solution.
NaCl, KNO3, HNO3, NaOH
Weak - conduct only a small current - few ions in solution,
HC2H3O2, aq. NH3, tap H2O
Non - no current flows - no ions in solution.
pure H2O, sugar solution, glycerol

24. Formation of Precipitate
K2CrO4(aq) + Ba(NO3)2(aq) ----> BaCrO4(s) + 2KNO3(aq)

25. Common Terms of Solution Concentration
Stock - routinely used solutions prepared in concentrated form.
Concentrated - relatively large ratio of solute to solvent. (5.0 M NaCl)
Dilute - relatively small ratio of solute to solvent. (0.01 M NaCl)

26. Concentration Molarity = moles of solute Liter of solution
-- most often used in chemistry
Molality = moles of solute
kg of solvent
-- molar mass, freezing point depressions, & boiling point elevations

27. Molarity Calculations
If 1.00 g of ethanol is dissolved in enough water to make 101 mL of solution, what is the molarity of the solution?

28. Molarity Calculations
Calculate the molarity of a solution prepared by dissolving 11.5 g of solid NaOH in enough water to make 1.50 L of solution.
(11.5g NaOH/1.50L)(1 mol NaOH/40.00g NaOH)
= M NaOH

29. Molarity Calculations
How many moles of nitrate ions are present in mL of a 0.75 M Co(NO3)2 solution?
(25.00mL)(1L/1000mL)(0.75mol Co(NO3)2/1L)
(2 mol NO3-/1 mol Co(NO3)2) = 3.8 x 10-2 mol NO3-

30. Standard Solution

31. When diluting stock solutions, the moles of solute after dilution must equal the moles of solute before dilution.

32. Dilution Calculations
What volume of 16 M sulfuric acid must be used to prepare 1.5 L of a 0.10 M H2SO4 solution?
(0.10mol H2SO4/1L)(1.5L)(1L/16mol)(1000mL/1L)
= 9.4 mL conc H2SO4