1. Titrations
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2. Titrations can be used in the analysis of Acid-base reactions
Redox reactions
H2SO4 + 2NaOH H2O + Na2SO4
5Fe2+ + MnO4- + 8H Mn Fe3+ + 4H2O

3. Neutralization Reaction
acid + base salt + water
HCl (aq) + NaOH (aq) NaCl (aq) + H2O
H+ + Cl- + Na+ + OH Na+ + Cl- + H2O
H+ + OH H2O

4. In a titration, a solution of accurately known concentration (standard) is added gradually added to another solution of unknown concentration (analyte) until the chemical reaction between the two solutions is complete.

5. Equivalence point – the point at which the reaction is complete
mol H+ = mol OH−
Video

6. Indicator – substance that changes color at (or near) the
equivalence point
End point – the point which the indicator used in titration changes color
Slowly add base
to unknown acid
UNTIL
the indicator
changes color
(pink)

8. Solutions of Red Cabbage ExtractpH

10. KHC8H4O4(aq) + NaOH(aq) KNaC8H4O4(aq) + H2O(l)
In a titration experiment, a student finds that mL of a NaOH solution are needed to neutralize g of a weak acid known as KHP (potassium hydrogen phthalate, KHC8H4O4). What is the concentration (in molarity) of the NaOH solution?
KHC8H4O4(aq) + NaOH(aq) KNaC8H4O4(aq) + H2O(l)
Answer to Practice Exercise: g
Practice: How many grams of KHP are needed to neutralize mL of a M NaOH solution?

11. How many milliliters (mL) of a 0
How many milliliters (mL) of a M NaOH solution are needed to neutralize 20.0 mL of a M H2SO4 solution?
Answer to Practice Exercise: 10.1 mL
Practice: How many milliliters of a 1.28 M sulfuric acid solution are needed to neutralize 60.2 mL of a M potassium hydroxide solution?

12. A 16. 42-mL volume of 0. 1327 M KMnO4 solution is needed to oxidize 25
A mL volume of M KMnO4 solution is needed to oxidize mL of a FeSO4 solution in an acidic medium. What is the concentration of the FeSO4 solution in molarity? The net ionic equation is
Answer to Practice Exercise: 204 mL
Practice: How many milliliters of a M hydroiodic acid solution are needed to reduce 22.5 mL of a potassium permanganate solution according to the following equation:
10HI + 2KMnO4 + 3H2SO4 5I2 + K2SO4 + 8H2O

13. Strong Acid-Strong Base Titrations
NaOH (aq) + HCl (aq) H2O (l) + NaCl (aq)
OH- (aq) + H+ (aq) H2O (l)

14. The titration curve of a strong acid with a strong base.

15. Weak Acid-Strong Base Titrations
CH3COOH (aq) + NaOH (aq) CH3COONa (aq) + H2O (l)
CH3COOH (aq) + OH- (aq) CH3COO- (aq) + H2O (l)
At equivalence point (pH > 7)

16. Strong Acid-Weak Base Titrations
HCl (aq) + NH3 (aq) NH4Cl (aq)
H+ (aq) + NH3 (aq) NH4+ (aq)
At equivalence point (pH < 7)