1. Chapter 13- Solutions
Today is the last day to contact me about Exam #1
NEW OWL HOMEWORK HAS BEEN POSTED

2. Last time… Solubility of molecular (covalent) compounds Polymers
Enthalpic vs. entropic considerations
Enthalpy of mixing of hydrocarbons is slightly negative (favorable)
Dissolution is NOT favored when water becomes ordered, but it IS favored when the solute forms strong bonds with water
Flavor compounds
Polymers
Properties determined by chemical makeup of monomer(s), length of polymer, branching/cross-linking
Shape determined by hydrophobicity and hydrophilicity of monomers
Proteins: Fold into functional shape based on hydrogen bonding and burial of hydrophobic surface area

3. What holds DNA together?

4. DNA, Hydrogen Bonding, and Entropy

5. Lipids and Membranes
Surfactants
Self-assembly

6. Surfactants and Cleaning

7. Solubility of Ionic Compounds

8. Solubility Rules for Ionic Compounds

9. Ionic Compounds- Control of Solubility
What happens to an ion when it dissolves?
Why aren’t all ionic compounds soluble?
Is dissolving an ionic compound exothermic or endothermic?

10. Ionic Compound Dissolution & Enthalpy
CaCl2
NH4NO3
∆Hdiss→
TREND?

11. Ionic Compound Dissolution & Entropy
∆Sdiss→
TREND?

12. Solubility Rules for Ionic Compounds

13. The dissolution of NH4NO3 is… (endo, T↓)
H favored
S favored
H and S favored
Can’t tell

14. The dissolution of CaCl2 is… (exo, T↑)
H favored
S favored
H and S favored
Can’t tell