1. Weak Acid – Strong Base Titration

2. The Parts of a Titration Curve

3. Weak Acid Before Stong Base is Added
HA  H+ + A-
HA A OH-

4. Stong Base is Added to the Weak Acid
-or-
Buffer
HA A OH-

5. The Endpoint is Reached
At Equivalence …
moles HA initial
moles base added
moles salt formed
CAUTION: Concentration is Moles/Liter
Salt of a SB and WA
HA A OH-

6. Beyond the Endpoint The Strong Base is Now Present
CAUTION: Concentration is Moles/Liter
The Strong Base is Now Present
HA A OH-

7. Finally … A Special Point
Look at the equation for a buffer
pKa
If mol A- formed is equal to mol HA remaining …
Halfway to the Endpoint
Therefore Ka =[H+]
pKa = pH
HA A OH-