1. Announcements Final Exam: Friday, May 14th at 8:00 am
What to Bring: Calculator
No. 2 Pencils
Two pages of notes
Format: Multiple choice (scantron)
Review Session: Wednesday, May 12th at 10:00am
IRC 3

2. Determine the pH of a weak acid solution from [acid]
What is the pH of a 0.15M solution of HF?

3. Predicting the pH of a weak acid: HCN
What is the pH of a 0.23M solution of HCN?
Ka= 4.0 x 10-10

4. Determine the pH of a strong base solution from [base]
What is the pH of a 0.15M solution of Ca(OH)2?

5. Polyprotic acids can donate >1 proton
H2CO HCO CO32-
H3PO H2PO HPO PO4 3-

7. How to determine whether a salt will be acidic or basic
Most acids are neutral
Most bases are anions
Salts
Look at cation and anion
Determine whether ions are acid/base/neutral
NH4+ = only acidic cation
Anions that are conjugates of strong A/B = neutral
Ions determine acidity/basicity of compound

8. Examples: Determining acid/base character of a salt
Compound
Cation
Anion
Acidic or Basic?
NaCN
KNO3
NH4Cl
NaHCO2
Na2CO3
NH4CN

9. What makes an acid strong or weak?
H-A → H+ + A-
To act as an acid, two things must happen:
H-A bond must break
“A” takes both electrons to make “A-”

10. Acid strength is related to bond strength and electronegativity
As bond strength increases, acid strength decreases
As electronegativity increases, acid strength increases

11. Lewis Acids and Bases

12. Lewis Acid Examples