titration curve separate definitions

-          To get the pH: Do a RICE problem with the initial [ ] of acid

point 1

-          Before the titration begins

point 1

-          Before the equivalence point

Region A

-          The middle part of this region doesn’t change much because it is a buffer

region A

-          To get the pH: determine the moles of acid remaining and the moles of conjugate base produced, divide both by the new total volume, plug into the Henderson-Hasselbach equation to get the pH.

region A

-          [HA] > [A^-] in this region before the midpoint

region A

[A-] > [HA] after midpoint

region A

-          Moles of base added equals half the moles of acid you started with

point 2

-          [HA] = [A^-]

point 2

-          Volume of titrant added equals half the volume of titrant added at equivalence point

point 2

-          Half-equivalence point

point 2

pH = pKa

point 2

midpoint

point 2

can be used to determine identity of unknown acid based on Ka

point 2

indicator should have pKa equal to pH at this point

point 3

-          To get the pH: determine the moles of conjugate base produced, divide by the new total volume, use a RICE problem of the conjugate base with water to determine the pH

point 3

-          Moles of acid you started with equals the moles of base added

point 3

-          The indicator should (if chosen correctly) change colour here

point 3

-          Equivalence point

point 3

-          Can be seen on a pH curve by picking a point halfway up the rapid-rise region

point 3

-          Can be used to calculate the molarity or weight % of the analyte

point 3

-          To get the pH: determine the moles of base/titrant remaining, divide by the new total volume, and take the –log[base] and subtract from 14

region B

[A-] can be ignored, but is present

region B

-          Excess base has been added beyond the point at which all the acid has been neutralized

region B

beyond the equivalence point

region B

[HA] = 0 (pretty much)

region B