Acid-Base Titration and pH

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Chapter 16

• Acid-Base Titration and pH

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Chapter 16.1

• In the self-ionization of water, two water
  molecules produce a hydronium ion and a hydroxide
  ion by transfer of a proton.
• Kw H3O OH-
• Kw 1.0 X 10 -14 M2

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• The pH of a solution is defined as the negative
  of the common logarithm of the hydronium ion
  concentration.
• The pH scale 0-14. 7 is neutralpHlt7 acidpHgt7
  base
• pH -log ( H3O)

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Chapter 16.2

• Acid-base indicators are compounds whose colors
  are sensitive to pH.
• pH range over which an indicator changes color is
  called its transition interval.
• pH meter determines the pH of a solution by
  measuring the voltage between the two electrodes
  that are placed in the solution.

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• Titration is the controlled addition and
  measurement of the amount of a solution of known
  concentration required to react completely with a
  measured amount of a solution of unknown
  concentrations.
• Equivalence point is the point at which the two
  solutions used in a titration are present in
  chemically equivalent amounts.
• End point is the point in a titration at which an
  indicator changes color.

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Titration Problems

1. Balance equation
2. Use the known solution to figure out the number
   of moles (Mmol/L)
3. Use the mole to mole ratio to figure out the
   moles of the unknown.
4. Determine the Molarity of the unknown using the
   given volume

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• Flask. May 7, 2007. http//www.chem.ualberta.ca/
  iip/chem211irc/TotalSalt(start).jpg
• Lets Titrate. May 7, 2007. http//genchem.rutge
  rs.edu/aanimate.gif
• Titration curve. May 7, 2007.
  http//www.cofc.edu/kinard/Applets/WeakAcidTitrat
  ion.gif