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Ionization of Water. CHEM 7784 Biochemistry Professor Bensley. Chapter 2.2 Ionization of Water. How weak acids and bases behave in water. Today’s Objective : to understand. H 2 O H + + OH -. . . Ionization of Water. Let’s do the “Proton Hop”.
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Ionization of Water CHEM 7784 Biochemistry Professor Bensley
Chapter 2.2Ionization of Water • How weak acids and bases behave in water Today’s Objective: to understand
H2O H+ + OH- Ionization of Water Let’s do the “Proton Hop”
H20 + H20 H3O+ + OH- Ionization of Water H20 H+ + OH- Keq=1.8 X 10-16M Keq= [H+] [OH-] [H2O] [H2O] = 55.5 M [H2O] Keq = [H+] [OH-] (1.8 X 10-16M)(55.5 M ) = [H+] [OH-] 1.0 X 10-14 M2 = [H+] [OH-] = Kw If [H+]=[OH-] then [H+] = 1.0 X 10-7
What is pH? pH = -log[H+]
Dissociation of Weak Electrolytes: Example What is the final pH of a solution when 0.1 moles of acetic acid is adjusted to 1 L of water? 0.1 – x x x
Dissociation of Weak Electrolytes: Simplification 0.1 – x x x 0.1 x x
pKa measures acidity pKa = -log Ka (strong acid large Ka small pKa)