Weak Acid – Strong Base Titration

The Parts of a Titration Curve

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

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

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-

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

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-