1. Titration Curves I. Strong Acid + Strong Base 0.1 M HCl 0.1 M NaOH
25.0 mL
25.0 mL
2.5 x 10-3mol
2.5 x 10-3mol
1. Initial pH
HCl  H+
+ Cl-
0.1 M
0.1 M
[H+] =
0.1 M
pH =
- log H+
= 1.00 .

2. Strong Acid + Strong Base 0.1 M HCl 0.1 M NaOH 25.0 mL 10.0 mL
2.5 x 10-3mol -
1.0x 10-3 mol
= 1.5 x 10-3 mol
V = mL
[H+] =
1.5 x 10-3 mol
35 x 10-3 L
[H+] =
4.28 x 10-2 M .
pH =
1.37 .

3. Strong Acid + Strong Base 0.1 M HCl 0.1 M NaOH 25.0 mL 20.0 mL
2.5 x 10-3mol -
2.0 x 10-3 mol
= 0.5 x 10-3 mol
V = mL
[H+] =
0.5 x 10-3 mol
45 x 10-3 L
[H+] =
1.11 x 10-2 M . .
pH =
1.95 .

4. Strong Acid + Strong Base 0.1 M HCl 0.1 M NaOH 25.0 mL 25.0 mL
2.5 x 10-3mol -
2.5 x 10-3 mol
= 0.0 mol
[H+] =
1.00 x 10-7 M .
pH =
7.00 . . .

5. Strong Acid + Strong Base 0.1 M HCl 0.1 M NaOH 25.0 mL 35.0 mL
2.5 x 10-3mol
3.5 x 10-3 mol OH-
V = mL
[OH-] =
1.0 x 10-3 mol .
60 x 10-3 L .
[OH-] =
1.67 x 10-2 M . .
pOH =
1.78 .
pH =
12.22

6. Titration Curves Weak Acid + Strong Base 0.1 M CH3COOH 0.1 M NaOH
25.0 mL
25.0 mL
Initial
weak acid
pH = pKa + log [CH3COO-]
[CH3COOH]
Ka = 1.8 x 10-5
= [H+] [CH3COO-]
[CH3COOH]
half-way point
pH = pKa
= 4.74
equivalence point
CH3COO-
+ H2O 
CH3COOH
+ OH-
Kb = 5.6 x 10-10
= [OH-] [CH3COOH]
[CH3COO-]
strong base

7. Titration Curves Weak Base + Strong Acid 0.1 M NH3 0.1 M HCl 25.0 mL
1. Initial pH
NH3
+ H2O 
NH4+
+ OH-
Kb=
1.8 x 10-5 =
[OH-]
[NH4+]
[NH3]
[OH-] =
1.34 x 10-3 M
pOH =
2.87
pH = 11.12

8. Titration Curves . Weak Base + Strong Acid 0.1 M NH3 0.1 M HCl 25.0 mL
2.5 x 10-3mol -
1.0 x 10-3 mol
= 1.5 x 10-3 mol
V = mL
x = 2.67 x 10-5
pOH = 4.57
NH3
+ H2O 
NH4+
+ OH-
pH = 9.43
Kb=
1.8 x 10-5 =
[NH4+]
[OH-]
[NH3] .
[NH3] [NH4+] [OH-]
0.043
0.029
0.0 x x x
1.8 x 10-5 =
[x]
[ x]
[ x]

9. Titration Curves . . Weak Base + Strong Acid 0.1 M NH3 0.1 M HCl
25.0 mL
20.0 mL
2.5 x 10-3mol -
2.0 x 10-3 mol
= 5.0 x 10-4 mol
V = mL
x = 4.5 x 10-6
pOH = 5.35
NH3
+ H2O 
NH4+
+ OH-
pH = 8.65
Kb=
1.8 x 10-5 =
[NH4+]
[OH-]
[NH3] . .
[NH3] [NH4+] [OH-]
0.011
0.044
0.0 x x x
1.8 x 10-5 =
[x]
[ x]
[ x]

10. Titration Curves . . . Weak Base + Strong Acid 0.1 M NH3 0.1 M HCl
25.0 mL
25.0 mL
2.5 x 10-3mol -
2.5 x 10-3 mol
= 0.00
V = mL
x = 5.9 x 10-6
pH = 5.27
NH4+ 
NH3
+H+
Ka=
5.6 x =
[NH3]
[H+]
[NH4+] . .
[NH4] [NH3] [H+]
0.05
0.00
0.0 .
0.05 -x x x
5.6 x =
[x2]
[ x]

11. Titration Curves Weak Base + Strong Acid 0.1 M NH3 0.1 M HCl 25.0 mL
pH = 8.65
2.5 x 10-3mol
Ka = 1.8 x 10-5
pOH = pKb + log [NH4+]
[NH3]
5.0 x 10-4 mol NH3
2.0 x 10-3 mol NH4+
V = 45 x 10-3 L
pOH =
4.74
+ log (0.44)
(0.11)
= 5.34

12. Polyprotic Acid H2SO3  HSO3- + H+ Ka1 = 1.4 x 10-2 HSO3-  SO32- + H+
2 equivalents of base
0.10 M H2SO3
0.10 M NaOH
40 mL
80 mL
Initial pH
1.4 x 10-2 =
[HSO3-]
[H+]
= x2
[H2SO3]
0.1 - x
x = 0.03
pH = 1.51

13. Polyprotic Acid . . . . H2SO3  HSO3- + H+ Ka1 = 1.4 x 10-2 HSO3- 
2 equivalents of base
0.10 M H2SO3
0.1 M NaOH
buffering regions
half-way point
pH = pKa
- log 1.4 x 10-2 =
1.85
- log 6.5 x 10-8 =
7.19 .
1st equivalence point .
= 4.52 . 2 .
2nd equivalence point
conjugate base, SO3-

14. Polyprotic Acid
H2SO3 
HSO3-
+ H+
Ka1 = 1.4 x 10-2
HSO3- 
SO32-
+ H+
Ka2 = 6.5 x 10-8
2 equivalents of base
0.10 M H2SO3
0.1 M NaOH
40 mL
80 mL
Initial pH
1.4 x 10-2 =
[HSO3-]
[H+]
= x2
x = 0.03
[H2SO3]
0.1 - x
pH = 1.51