1. Buffers

2. Buffer…. Weak acid + its conjugate base Or
Weak base + its conjugate acid

4. Which of following pairs make a buffer?
A. NH3, NH4Cl
B. RbOH, HBr
C. KOH, HF
D. NaC2H3O2, HCl

5. To review: Directly add Weak acid + weak base conjugate pair Or
Indirectly by Weak acid + strong base (and it will make the weak form the needed conjugate) or
weak base + strong acid (and it will make the weak form the needed conjugate)

6. Calculate the pH of a buffer solution that contains 0
Calculate the pH of a buffer solution that contains 0.15M of acetic acid and 0.20mol of sodium acetate in 1L. (Ka =1.8 x 10-5)
Solve by icebox then solve by Henderson hasselbach
HC2H3O H C2H3O2-

7. ph = 4.87