Titration

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Titration

• Ch. 15.2

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A. Neutralization

• Chemical reaction between an acid and a base.
• Products are a salt and water.
• A salt is an ionic compound that forms between
  the cation of a base and the anion of the acid.
• Neutralization Animation

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A. Neutralization

• ACID BASE ? SALT WATER

HCl NaOH ? NaCl H2O
HC2H3O2 NaOH ? NaC2H3O2 H2O

• Neutralization does not mean pH 7.

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Neutralization
HCl NaOH ? NaCl H2O
strong
strong
neutral
HC2H3O2 NaOH ? NaC2H3O2 H2O
weak
strong
basic

• Although most salts are neutral, some react with
  water through hydrolysis to become acidic or
  basic.

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A. Neutralization

• Review
• Acidic Solutions H3O gt OH-
• Basic Solutions H3O lt OH-
• Neutral Solutions H3O OH-

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B. Titration

• Titration
• Laboratory method in which a standard solution is
  used to determine the concentration of an unknown
  solution.

buret
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B. Titration

• Equivalence point
• Point at which equal amounts of H3O and OH- have
  been added.
• Usually the same as the end point, which is
  determined by
• indicator color change

• dramatic change in pH (as seen on graph)

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C. Titration Calculations
moles H3O moles OH- M?V? n M?V? n
M Molarity V volume n of H ions in the
acid or OH- ions in the base
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C. Titration Calculations

• 42.5 mL of 1.3M KOH are required to neutralize
  50.0 mL of H2SO4. Find the molarity of H2SO4.

H3O M ? V 50.0 mL n 2
OH- M 1.3M V 42.5 mL n 1
MV MV M(50.0mL)(2) (1.3M)(42.5mL)(1) M
0.55M H2SO4
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C. Titration Calculations

• You try
• 27.4 mL of 0.0154M Ba(OH)2 are required to
  neutralize 20.0 mL of HCl. Find the molarity of
  HCl.

H3O M ? V 20.0 mL n 1
OH- M 0.0154 M V 27.4 mL n 2
MV MV M(20.0mL)(1) (0.0154M)(27.4mL)(2) M
0.0422 M HCl