1. Driving reactions to completion

2. Driving reactions to completion
Completion = 100% yield of product

3. Cl-(aq) + Ag+(aq) AgCl(s)

4. Cl-(aq) + Ag+(aq) AgCl(s)
AgCl precipitates from the
solution.

5. Cl-(aq) + Ag+(aq) AgCl(s)
AgCl precipitates from the
solution.
As the AgCl precipitates,
product is removed from solution.

7. Cl-(aq) + Ag+(aq) AgCl(s)

8. All gases
N2 + 3 H NH3

9. All gases
N2 + 3 H NH3
exothermic

10. All gases
N2 + 3 H NH3
exothermic
cool

11. All gases
N2 + 3 H NH3
exothermic
cool

12. N2 + 3 H NH3
Although a lower temperature
favors more NH3 formed, the
lower temperature also leads to
a very slow reaction.

13. N2 + 3 H NH3
An increase in pressure should favor product.

14. N2 + 3 H NH3
An increase in pressure should favor product.

15. N2 + 3 H NH3
Ultimate solution: react at high
Temperature to speed up reaction,
cool until NH3 becomes liquid.
Remove from reaction vessel and repeat.

16. C O N E T R A I
(time)

17. Heterogeneous equilibrium

18. Heterogeneous equilibrium
Involves at least two phases.

19. Heterogeneous equilibrium
Involves at least two phases.
What is the concentration of
a pure liquid or a pure solid?

20. Concentrations are not a valid
way to define a pure liquid
or solid.

21. Concentrations are not a valid
way to define a pure liquid
or solid.
Moles water = ?
Liters solvent

22. The concentration of a pure liquid
or solid is defined as 1.

23. Law of Mass Action

24. Law of Mass Action
1. Gases enter equilibrium expressions
as partial pressures in atmospheres.

25. Law of Mass Action
1. Gases enter equilibrium expressions
as partial pressures in atmospheres.
2. Dissolved species enter as
concentrations in mol L-1.

26. Law of Mass Action
1. Gases enter equilibrium expressions
as partial pressures in atmospheres.
2. Dissolved species enter as
concentrations in mol L-1.
3. Pure solids and liquids are represented by 1
at equilibrium , a dilute solvent is 1.

27. Law of Mass Action
1. Gases enter equilibrium expressions
as partial pressures in atmospheres.
2. Dissolved species enter as
concentrations in mol L-1.
3. Pure solids and liquids are represented by 1
at equilibrium , a dilute solvent is 1.
4. Partial pressures or concentrations of
products appear in the numerator, reactants in
the denominator. Each is raised to the power
of its coefficient.

28. The partition coefficient:

29. The partition coefficient:
Materials are soluble to different
degrees in different solvents.

30. The partition coefficient:
Materials are soluble to different
degrees in different solvents.
This allows for a method to separate that
material from others.

31. Solvent a
Solvent b
Compound x

32. Solvent a
Solvent b
Compound x
[x]a  [x]b

33. [x]a  [x]b
Partition coefficient =
K =
[x]b
[x]a

34. I2
H2O
CCl4

35. I2
H2O and
CCl4 are
immiscible
H2O
CCl4

36. I2(H2O) I2(CCl4)
H2O
CCl4

37. I2(H2O) I2(CCl4)
[I2]CCl4
K =
[I2]H2O
H2O
CCl4

38. I2(H2O) I2(CCl4)
[I2]CCl4
K =
[I2]H2O
H2O
= 85
Partition
coefficient
CCl4

39. Acids and Bases

40. Acids and Bases
Arrhenius Acids and Bases

41. Acids and Bases
Arrhenius Acids and Bases
Acid : increases H+ concentration
in water.

42. Acids and Bases
Arrhenius Acids and Bases
Acid : increases H+ concentration
in water.
Base : increases OH- concentration
in water.

43. Acids and Bases
Brønsted-Lowrey Acids and Bases

44. Acids and Bases
Brønsted-Lowrey Acids and Bases
Acid : substance that can donate H+.

45. Acids and Bases
Brønsted-Lowrey Acids and Bases
Acid : substance that can donate H+.
Base : substance that can accept H+.

46. Acids and Bases
Brønsted-Lowrey Acids and Bases
Acid : substance that can donate H+.
Base : substance that can accept H+.
Do not require aqueous solutions.

47. Acids and Bases
Brønsted-Lowrey Acids and Bases
Conjugate acid-base pairs.

48. Acids and Bases
Brønsted-Lowrey Acids and Bases
Conjugate acid-base pairs.
Conjugate base: subtract H+ from acid
formula.

49. Acids and Bases
Brønsted-Lowrey Acids and Bases
Conjugate acid-base pairs.
Conjugate base: subtract H+ from acid
formula.
Conjugate acid: add H+ to the base formula.

50. Conjugate acid-base pairs.

51. Conjugate acid-base pairs.
CH3COOH(aq) + H2O(l)

52. Conjugate acid-base pairs.
CH3COOH(aq) + H2O(l)
Acetic acid is a monoprotic acid.

53. Conjugate acid-base pairs.
CH3COOH(aq) + H2O(l)
H3O+(aq) + CH3COO-(aq)

54. Conjugate acid-base pairs.
CH3COOH(aq) + H2O(l)
H3O+(aq) + CH3COO-(aq)
CH3COOH donates H+ = acid

55. Conjugate acid-base pairs.
CH3COOH(aq) + H2O(l)
H3O+(aq) + CH3COO-(aq)
CH3COOH donates H+ = acid
H2O accepts H+ = base

56. Conjugate acid-base pairs.
CH3COOH(aq) + H2O(l)
H3O+(aq) + CH3COO-(aq)
CH3COOH donates H+ = acid
CH3COO- = conjugate base
H2O accepts H+ = base

57. Conjugate acid-base pairs.
CH3COOH(aq) + H2O(l)
H3O+(aq) + CH3COO-(aq)
CH3COOH donates H+ = acid
CH3COO- = conjugate base
H2O accepts H+ = base
H3O+ = conjugate acid

58. Conjugate acid-base pairs.
CH3COOH(aq) + H2O(l)
acid1
base2
H3O+(aq) + CH3COO-(aq)
acid2
base1
CH3COOH donates H+ = acid
CH3COO- = conjugate base
H2O accepts H+ = base
H3O+ = conjugate acid

59. Conjugate acid-base pairs.
H2O
H2O H+ + OH-

60. Conjugate acid-base pairs.
H2O
H2O H+ + OH-
H2O donates H+ = acid

61. Conjugate acid-base pairs.
H2O
H2O H+ + OH-
H2O donates H+ = acid
H2O + H H3O+

62. Conjugate acid-base pairs.
H2O
H2O H+ + OH-
H2O donates H+ = acid
H2O + H H3O+
H2O accepts H+ = base

64. +

65. + +

66. Conjugate acid-base pairs.
Conjugate base: subtract H+ from acid
formula.
Conjugate acid: add H+ to the base formula.

67. Conjugate acid-base pairs.
H2O
H2O H+ + OH-
H2O donates H+ = acid
Conjugate base = OH-
H2O + H H3O+
H2O accepts H+ = base
Conjugate acid = H3O+

68. Conjugate acid-base pairs.
H2O
H2O H+ + OH-
H2O donates H+ = acid
Conjugate base = OH-
H2O + H H3O+
H2O accepts H+ = base
Conjugate acid = H3O+
H2O can be both conjugate acid and base.

69. Trimethyl amine is a weak base.
What is the conjugate acid?

70. Trimethyl amine is a weak base.
What is the conjugate acid?
(CH3)3N

71. Trimethyl amine is a weak base.
What is the conjugate acid?
(CH3)3N

72. Trimethyl amine is a weak base.
What is the conjugate acid?
[(CH3)3NH]+
Conjugate acid

73. NaCN dissolved in water gives
a basic solution. Why?

74. NaCN dissolved in water gives
a basic solution. Why?
NaCN(s) + H2O(l) Na+(aq) + CN-(aq) + H2O(l)

75. NaCN dissolved in water gives
a basic solution. Why?
NaCN(s) + H2O(l) Na+(aq) + CN-(aq) + H2O(l)

76. NaCN dissolved in water gives
a basic solution. Why?
NaCN(s) + H2O(l) Na+(aq) + CN-(aq) + H2O(l)
+ H2O(l) HCN(aq) + OH-(aq)

77. Non-aqueous solutions

78. Non-aqueous solutions
NH3(l)

79. Non-aqueous solutions
HCl(NH ) + NH3(l) NH4+(NH ) + Cl-(NH ) 3 3 3

80. Non-aqueous solutions
HCl(NH ) + NH3(l) NH4+(NH ) + Cl-(NH ) 3 3 3
acid1
base2
acid2
base1

81. Non-aqueous solutions
HCl(NH ) + NH3(l) NH4+(NH ) + Cl-(NH ) 3 3 3
acid1
base2
acid2
base1
Ammonia is the solvent.

82. Amphoteric molecules

83. Amphoteric molecules
An amphoteric molecule or ion can be
either an acid or a base depending on
conditions.

84. Amphoteric molecules
An amphoteric molecule or ion can be
either an acid or a base depending on
conditions.
water

85. Amphoteric molecules
An amphoteric molecule or ion can be
either an acid or a base depending on
conditions.
water
H3O+

86. Amphoteric molecules
An amphoteric molecule or ion can be
either an acid or a base depending on
conditions.
water
H3O+
OH-

87. Amphoteric molecules
Hydrogen carbonate ion

88. Amphoteric molecules
Hydrogen carbonate ion
HCO3-

89. Amphoteric molecules
Hydrogen carbonate ion
HCO3-(aq) + H2O(l) H2CO3(aq) + OH-(aq)

90. Hydrogen carbonate ion
Amphoteric molecules
Hydrogen carbonate ion
HCO3-(aq) + H2O(l) H2CO3(aq) + OH-(aq)
base1
acid2
acid1
base2

91. Hydrogen carbonate ion
Amphoteric molecules
Hydrogen carbonate ion
HCO3-(aq) + H2O(l) H2CO3(aq) + OH-(aq)
base1
acid2
acid1
base2
HCO3-(aq) + H2O(l) CO32-(aq) + H3O+(aq)

92. Hydrogen carbonate ion
Amphoteric molecules
Hydrogen carbonate ion
HCO3-(aq) + H2O(l) H2CO3(aq) + OH-(aq)
base1
acid2
acid1
base2
HCO3-(aq) + H2O(l) CO32-(aq) + H3O+(aq)
acid1
base2
base1
acid2

93. Acids and Bases
Brønsted-Lowrey Acids and Bases
Acid : substance that can donate H+.
Base : substance that can accept H+.

94. Acids and Bases
Brønsted-Lowrey Acids and Bases
Acid : substance that can donate H+.
Dependant on strength of base present.
Base : substance that can accept H+.

95. Acids and Bases
Brønsted-Lowrey Acids and Bases
Acid : substance that can donate H+.
Dependant on strength of base present.
Base : substance that can accept H+.
Dependant on strength of acid present.

96. The pH scale

97. The pH scale
Water always has some H3O+ and
OH- present.

98. The pH scale
Water always has some H3O+ and
OH- present.
2 H2O(l) H3O+(aq) + OH-(aq)

99. The pH scale
Water always has some H3O+ and
OH- present.
2 H2O(l) H3O+(aq) + OH-(aq)
[H3O+][OH-]
KW =
[H2O]2

100. The pH scale
Water always has some H3O+ and
OH- present.
2 H2O(l) H3O+(aq) + OH-(aq)
[H3O+][OH-]
[H3O+][OH-]
KW = =
[H2O]2

101. The pH scale
Water always has some H3O+ and
OH- present.
2 H2O(l) H3O+(aq) + OH-(aq)
[H3O+][OH-]
[H3O+][OH-]
= 1.0 x10-14
KW = =
[H2O]2
@ 25oC

102. KW =
[H3O+][OH-]
= 1.0 x10-14
@ 25oC

103. KW =
[H3O+][OH-]
= 1.0 x10-14
@ 25oC
If [H3O+] = [OH-] what are their
concentrations at 25oC?

104. KW =
[H3O+][OH-]
= 1.0 x10-14
@ 25oC
If [H3O+] = [OH-] what are their
concentrations at 25oC?
[X][X] = 1.0 x 10-14

105. KW =
[H3O+][OH-]
= 1.0 x10-14
@ 25oC
If [H3O+] = [OH-] what are their
concentrations at 25oC?
[X][X] = 1.0 x 10-14
X2 = 1.0 x 10-14

106. KW =
[H3O+][OH-]
= 1.0 x10-14
@ 25oC
If [H3O+] = [OH-] what are their
concentrations at 25oC?
[X][X] = 1.0 x 10-14
X2 = 1.0 x 10-14
X = 1.0 x 10-7

107. pH = -log10[H3O+]

108. pH = -log10[H3O+]
[H3O+] = 1.0 x 10-7

109. pH = -log10[H3O+]
[H3O+] = 1.0 x 10-7
-log10(1.0 x 10-7) =

110. pH = -log10[H3O+]
[H3O+] = 1.0 x 10-7
-log10(1.0 x 10-7) = -1 x -7 = 7
pH neutral water = 7

111. pH of a water solution of a
strong acid.

112. pH of a water solution of a
strong acid.
HCl(aq) + H2O(l) H3O+(aq) + Cl-(aq)

113. pH of a water solution of a
strong acid.
HCl(aq) + H2O(l) H3O+(aq) + Cl-(aq)
Assume HCl dissociates 100%.

114. pH of a water solution of a
strong acid.
HCl(aq) + H2O(l) H3O+(aq) + Cl-(aq)
Assume HCl dissociates 100%.
0.1 M HCl M H3O+

115. pH of a water solution of a
strong acid.
HCl(aq) + H2O(l) H3O+(aq) + Cl-(aq)
Assume HCl dissociates 100%.
0.1 M HCl M H3O+
[H3O+] = 1.0 x 10-1 M

116. pH of a water solution of a
strong acid.
HCl(aq) + H2O(l) H3O+(aq) + Cl-(aq)
Assume HCl dissociates 100%.
0.1 M HCl M H3O+
[H3O+] = 1.0 x 10-1 M
pH = 1

117. pH of a water solution of a
strong base.
KOH(aq) + H2O(l) K+(aq) + OH-(aq) + H2O(l)

118. pH of a water solution of a
strong base.
KOH(aq) + H2O(l) K+(aq) + OH-(aq) + H2O(l)
[KOH] = 0.1 M

119. pH of a water solution of a
strong base.
KOH(aq) + H2O(l) K+(aq) + OH-(aq) + H2O(l)
[KOH] = 0.1 M
KW = 1.0 x = [H3O+][OH-]

120. pH of a water solution of a
strong base.
KOH(aq) + H2O(l) K+(aq) + OH-(aq) + H2O(l)
[KOH] = 0.1 M
KW = 1.0 x = [H3O+][OH-]
1.0 x 10-14
[H3O+] =
0.1

121. pH of a water solution of a
strong base.
KOH(aq) + H2O(l) K+(aq) + OH-(aq) + H2O(l)
[KOH] = 0.1 M
KW = 1.0 x = [H3O+][OH-]
1.0 x 10-14
[H3O+] =
= 1.0 x 10-13
0.1

122. pH of a water solution of a
strong base.
KOH(aq) + H2O(l) K+(aq) + OH-(aq) + H2O(l)
1.0 x 10-14
[H3O+] =
= 1.0 x 10-13
0.1
pH = -log x =

123. pH of a water solution of a
strong base.
KOH(aq) + H2O(l) K+(aq) + OH-(aq) + H2O(l)
1.0 x 10-14
[H3O+] =
= 1.0 x 10-13
0.1
pH = -log x = 13

124. Exercise page 330
Compute pH of aqueous solution
having [H3O+] = 2x[OH-].

125. Exercise page 330
Compute pH of aqueous solution
having [H3O+] = 2x[OH-].
KW = [H3O+][OH-] = 1.0 x 10-14

126. Exercise page 330
Compute pH of aqueous solution
having [H3O+] = 2x[OH-].
KW = [H3O+][OH-] = 1.0 x 10-14
(2x)(x) = 1.0 x 10-14

127. Exercise page 330
Compute pH of aqueous solution
having [H3O+] = 2x[OH-].
KW = [H3O+][OH-] = 1.0 x 10-14
(2x)(x) = 1.0 x 10-14
2x2 = 1.0 x 10-14

128. Exercise page 330
Compute pH of aqueous solution
having [H3O+] = 2x[OH-].
KW = [H3O+][OH-] = 1.0 x 10-14
(2x)(x) = 1.0 x 10-14
2x2 = 1.0 x 10-14
x2 = 0.5 x 10-14

129. Exercise page 330
Compute pH of aqueous solution
having [H3O+] = 2x[OH-].
KW = [H3O+][OH-] = 1.0 x 10-14
x2 = 0.5 x 10-14
x = 7.07 x 10-08

130. Exercise page 330
Compute pH of aqueous solution
having [H3O+] = 2x[OH-].
KW = [H3O+][OH-] = 1.0 x 10-14
x2 = 0.5 x 10-14
x = 7.07 x 10-08
2x = x 10-07

131. Exercise page 330
Compute pH of aqueous solution
having [H3O+] = 2x[OH-].
KW = [H3O+][OH-] = 1.0 x 10-14
x2 = 0.5 x 10-14
x = 7.07 x 10-08
2x = x 10-07
-log10 2x = 6.85

132. Calculating concentration from pH.

133. Calculating concentration from pH.
Example 8-4, page 330
pH = 2.85, calculate [H3O+] [OH-]

134. Calculating concentration from pH.
Example 8-4, page 330
pH = 2.85, calculate [H3O+] [OH-]
[H3O+] =

135. Calculating concentration from pH.
Example 8-4, page 330
pH = 2.85, calculate [H3O+] [OH-]
[H3O+] =
= 1.4 x 10-03

136. Calculating concentration from pH.
Example 8-4, page 330
pH = 2.85, calculate [H3O+] [OH-]
[H3O+] =
= 1.4 x 10-03
[H3O+] = 1.4 x M

137. [H3O+] = 1.4 x M
1.0 x 10-14
[OH-] = =
1.4 x 10-03

138. [H3O+] = 1.4 x M
1.0 x 10-14
7.1 x 10-12
[OH-] = =
1.4 x 10-03

139. Acids and bases of varying strengths.

140. Acids and bases of varying strengths.
Strong acid = 100% ionization
Strong acid = 100% donation of acidic
proton.

141. HCl(aq) + H2O(l) H3O+(aq) + Cl-(aq)

142. HCl(aq) + H2O(l) H3O+(aq) + Cl-(aq)
[H3O+][Cl-]
K =
[HCl]

143. HCl(aq) + H2O(l) H3O+(aq) + Cl-(aq)
[H3O+][Cl-]
large
K = =
[HCl]

144. Generic acid
HA(aq) + H2O(l) H3O+(aq) + A-(aq)

145. Generic acid
HA(aq) + H2O(l) H3O+(aq) + A-(aq)
[H3O+][A-]
= acidity
constant
= Ka
[HA]

146. Generic acid
HA(aq) + H2O(l) H3O+(aq) + A-(aq)
[H3O+][A-]
= acidity
constant
= Ka
[HA]
-log10 Ka = pKa

147. Acid Ka pKa
HI  -11
HCl   -7
H2SO   -2
CH3COOH x
Table page 332

148. Base strength

149. Base strength
Inversely related to strength of
conjugate acid.

150. Base strength
Inversely related to strength of
conjugate acid.
H2O(l) + B(aq) HB+(aq) + OH-(aq)
conjugate acid

151. H2O(l) + B(aq) HB+(aq) + OH-(aq)
[HB+][OH-]
= Kb
= basicity
constant
[B]

152. [HB+][OH-]
= Kb
= basicity
constant
[B]
[H3O+][B]
= acidity
constant
= Ka
[HB+]
[H3O+][OH-] = Kw

153. [HB+][OH-]
= Kb
= basicity
constant
[B]
[H3O+][B]
= acidity
constant
= Ka
[HB+]
Conjugate acid
[H3O+][OH-] = Kw
KbKa = Kw

154. [HB+][OH-]
= Kb
= basicity
constant
[B]
[H3O+][B]
= acidity
constant
= Ka
[HB+]
[H3O+][OH-] = Kw
KbKa = Kw
pKb + pKa = pKw

155. KbKa = Kw
pKb + pKa = pKw
Expressions can be used for any
conjugate acid-base pair in water.

156. Indicators :
Usually a weak organic acid that has a
color different from its conjugate base.

157. Indicators :
Usually a weak organic acid that has a
color different from its conjugate base.
HA + H2O H3O+ + A-