Titration Curves
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Titration Curves
description
Titration Curves. Titration Curves A titration curve is a graph of the pH changes that occur during an acid-base titration versus the volume of acid or base added. There are three types of titration curves. - PowerPoint PPT Presentation
Transcript of Titration Curves
Titration Curves
Titration Curves
A titration curve is a graph of the pH changes that occur during an acid-base titration versus the volume of acid or base added.
There are three types of titration curves.
You need to be able to recognize each and then choose a suitable indicator for that titration. The equivalence point is the end of a titration where the stoichiometry of the reaction is exactly satisfied, or moles H+ = moles OH-. The transition point refers to when an indicator changes color and [HInd] = [Ind-].
Choosing an Indicator
When you choose an indicator, you must pick one so that the transition point of the indicator matches the equivalence point of the titration.
When acid base titration is at the equivalence point, the acid has neutralized the base leaving only a salt and water.
The pH of the equivalence point depends on type of salt. Rule of thumb If the salt is neutral the equivalence point = 7
If the salt is basic the equivalence point = 9
If the salt is acidic the equivalence point = 5
1. Titration Curve: Strong Acid and Strong Base
HCl + KOH →
1. Titration Curve: Strong Acid and Strong Base
HCl + KOH → KCl + HOH
1. Titration Curve: Strong Acid and Strong Base
HCl + KOH → KCl + HOH
Indicator
1. Titration Curve: Strong Acid and Strong Base
HCl + KOH → KCl + HOH
Indicator pH = 7 Bromothymol Blue
1. Titration Curve: Strong Acid and Strong Base
HCl + KOH → KCl + HOH
Indicator pH = 7 Bromothymol Blue
50 mL of 0.10 M KOH is added to 25 mL of 0.10 M HCl
1. Titration Curve: Strong Acid and Strong Base
HCl + KOH → KCl + HOH
Indicator pH = 7 Bromothymol Blue
50 mL of 0.10 M KOH is added to 25 mL of 0.10 M HCl pH
Volume .10 M KOH added
14
7
0
0 25 50
1. Titration Curve: Strong Acid and Strong Base
HCl + KOH → KCl + HOH
Indicator pH = 7 Bromothymol Blue
50 mL of 0.10 M KOH is added to 25 mL of 0.10 M HCl pH
Volume .10 M KOH added
14
7
0
0.10 M HCl
0 25 50
1. Titration Curve: Strong Acid and Strong Base
HCl + KOH → KCl + HOH
Indicator pH = 7 Bromothymol Blue
50 mL of 0.10 M KOH is added to 25 mL of 0.10 M HCl pH
Volume .10 M KOH added
14
7
0
0.10 M HCl
0 25 50
Neutral Salt
1. Titration Curve: Strong Acid and Strong Base
HCl + KOH → KCl + HOH
Indicator pH = 7 Bromothymol Blue
50 mL of 0.10 M KOH is added to 25 mL of 0.10 M HCl pH
Volume .10 M KOH added
14
7
0
0.10 M HCl
0 25 50
Neutral Salt
0.10 M KOH
1. Titration Curve: Strong Acid and Strong Base
HCl + KOH → KCl + HOH
Indicator pH = 7 Bromothymol Blue
50 mL of 0.10 M KOH is added to 25 mL of 0.10 M HCl
pH
Volume .10 M KOH added
14
7
0
0 25 50
1. Titration Curve: Strong Acid and Strong Base
HCl + KOH → KCl + HOH
Indicator pH = 7 Bromothymol Blue
50 mL of 0.10 M KOH is added to 25 mL of 0.10 M HCl
pH
Volume .10 M KOH added
14
7
0
0 25 50
2. Titration Curve: Weak Acid and Strong Base
HCN + KOH →
2. Titration Curve: Weak Acid and Strong Base
HCN + KOH → KCN + HOH
2. Titration Curve: Weak Acid and Strong Base
HCN + KOH → KCN + HOH
Indicator
2. Titration Curve: Weak Acid and Strong Base
HCN + KOH → KCN + HOH
Indicator pH = 9 Phenolphthalein
2. Titration Curve: Weak Acid and Strong Base
HCN + KOH → KCN + HOH
Indicator pH = 9 Phenolphthalein
20 mL of 1.0 M HCN is added to 10 mL of 1.0 M KOH
2. Titration Curve: Weak Acid and Strong Base
HCN + KOH → KCN + HOH
Indicator pH = 9 Phenolphthalein
20 mL of 1.0 M HCN is added to 10 mL of 1.0 M KOH
pH
Volume 1.0 M HCN added
14
7
0
0 10 20
2. Titration Curve: Weak Acid and Strong Base
HCN + KOH → KCN + HOH
Indicator pH = 9 Phenolphthalein
20 mL of 1.0 M HCN is added to 10 mL of 1.0 M KOH
pH
Volume 1.0 M HCN added
14
7
0
1.0 M KOH
0 10 20
2. Titration Curve: Weak Acid and Strong Base
HCN + KOH → KCN + HOH
Indicator pH = 9 Phenolphthalein
20 mL of 1.0 M HCN is added to 10 mL of 1.0 M KOH
pH
Volume 1.0 M HCN added
14
7
0
1.0 M KOH Basic Salt
0 10 20
2. Titration Curve: Weak Acid and Strong Base
HCN + KOH → KCN + HOH
Indicator pH = 9 Phenolphthalein
20 mL of 1.0 M HCN is added to 10 mL of 1.0 M KOH
pH
Volume 1.0 M HCN added
14
7
0
1.0 M KOH Basic Salt
1.0 M HCN0 10 20
2. Titration Curve: Weak Acid and Strong Base
HCN + KOH → KCN + HOH
Indicator pH = 9 Phenolphthalein
20 mL of 1.0 M HCN is added to 10 mL of 1.0 M KOH
pH
Volume 1.0 M HCN added
14
7
0
1.0 M KOH Basic Salt
1.0 M HCN0 10 20
2. Titration Curve: Weak Acid and Strong Base
HCN + KOH → KCN + HOH
Indicator pH = 9 Phenolphthalein
20 mL of 1.0 M HCN is added to 10 mL of 1.0 M KOH
pH
Volume 1.0 M HCN added
14
7
0
0 10 20
2. Titration Curve: Weak Acid and Strong Base
HCN + KOH → KCN + HOH
Indicator pH = 9 Phenolphthalein
20 mL of 1.0 M HCN is added to 10 mL of 1.0 M KOH
pH
Volume 1.0 M HCN added
14
7
0
0 10 20
Buffer Zone
2. Titration Curve: Weak Acid and Strong Base
HCN + KOH → KCN + HOH
Indicator pH = 9 Phenolphthalein
20 mL of 1.0 M HCN is added to 10 mL of 1.0 M KOH
pH
Volume 1.0 M HCN added
14
7
0
0 10 20
Buffer Zone
Weak Acid & Salt
are present
3. Titration Curve: Strong Acid and Weak Base
HCl + NH3 →
3. Titration Curve: Strong Acid and Weak Base
HCl + NH3 → NH4+ + Cl-
3. Titration Curve: Strong Acid and Weak Base
HCl + NH3 → NH4+ + Cl-
Indicator
3. Titration Curve: Strong Acid and Weak Base
HCl + NH3 → NH4+ + Cl-
Indicator pH = 5 Methyl Red
3. Titration Curve: Strong Acid and Weak Base
HCl + NH3 → NH4+ + Cl-
Indicator pH = 5 Methyl Red
60 mL of 1.0 M NH3 is added to 30 mL of 1.0 M HCl
3. Titration Curve: Strong Acid and Weak Base
HCl + NH3 → NH4+ + Cl-
Indicator pH = 5 Methyl Red
60 mL of 1.0 M NH3 is added to 30 mL of 1.0 M HCl
pH
Volume 1.0 M NH3 added
14
7
0
0 30 60
3. Titration Curve: Strong Acid and Weak Base
HCl + NH3 → NH4+ + Cl-
Indicator pH = 5 Methyl Red
60 mL of 1.0 M NH3 is added to 30 mL of 1.0 M HCl
pH
Volume 1.0 M NH3 added
14
7
0
1.0 M HCl
0 30 60
3. Titration Curve: Strong Acid and Weak Base
HCl + NH3 → NH4+ + Cl-
Indicator pH = 5 Methyl Red
60 mL of 1.0 M NH3 is added to 30 mL of 1.0 M HCl
pH
Volume 1.0 M NH3 added
14
7
0
1.0 M HCl Acid Salt
0 30 60
3. Titration Curve: Strong Acid and Weak Base
HCl + NH3 → NH4+ + Cl-
Indicator pH = 5 Methyl Red
60 mL of 1.0 M NH3 is added to 30 mL of 1.0 M HCl
pH
Volume 1.0 M NH3 added
14
7
0
1.0 M HCl Acid Salt
0 30 60
1.0 M NH3
3. Titration Curve: Strong Acid and Weak Base
HCl + NH3 → NH4+ + Cl-
Indicator pH = 5 Methyl Red
60 mL of 1.0 M NH3 is added to 30 mL of 1.0 M HCl
1.0 M HCl Acid Salt
1.0 M NH3
pH
Volume 1.0 M NH3 added
14
7
0
0 30 60
3. Titration Curve: Strong Acid and Weak Base
HCl + NH3 → NH4+ + Cl-
Indicator pH = 5 Methyl Red
60 mL of 1.0 M NH3 is added to 30 mL of 1.0 M HCl
pH
Volume 1.0 M NH3 added
14
7
0
0 30 60
3. Titration Curve: Strong Acid and Weak Base
HCl + NH3 → NH4+ + Cl-
Indicator pH = 5 Methyl Red
60 mL of 1.0 M NH3 is added to 30 mL of 1.0 M HCl
pH
Volume 1.0 M NH3 added
14
7
0
0 30 60
Buffer Zone
Weak Base & Salt
are present
pH
Volume .10 M KOH added
14
7
0
0 25 50
4. Match the Curve with the Reaction
A. 3HCl + Al(OH)3 → AlCl3 + 3HOH
B. HCl + KOH → KCl + HOH
C. HCN + KOH → KCN + HOH
pH
Volume .10 M KOH added
14
7
0
0 25 50
A. 3HCl + Al(OH)3 → AlCl3 + 3HOH
B. HCl + KOH → KCl + HOH
C. HCN + KOH → KCN + HOH
Bisect the verticlepH = 7
4. Match the Curve with the Reaction
pH
Volume .10 M KOH added
14
7
0
0 25 50
A. 3HCl + Al(OH)3 → AlCl3 + 3HOH
B. HCl + KOH → KCl + HOH
C. HCN + KOH → KCN + HOH
Bisect the verticlepH = 7
4. Match the Curve with the Reaction
A. 3HCl + Al(OH)3 → AlCl3 + 3HOH
B. HCl + KOH → KCl + HOH
C. HCN + KOH → KCN + HOH
0 30 60
pH
Volume 1.0 M NH3 added
14
7
0
5. Match the Curve with the Reaction
A. 3HCl + Al(OH)3 → AlCl3 + 3HOH
B. HCl + KOH → KCl + HOH
C. HCN + KOH → KCN + HOH
pH
Volume 1.0 M NH3 added
14
7
0
0 30 60
Bisect the verticlepH = 5
5. Match the Curve with the Reaction
A. 3HCl + Al(OH)3 → AlCl3 + 3HOH
B. HCl + KOH → KCl + HOH
C. HCN + KOH → KCN + HOH
pH
Volume 1.0 M NH3 added
14
7
0
0 30 60
6. Match the Curve with the Reaction
A. 3HCl + Al(OH)2 → AlCl3 + 3HOH
B. HCl + KOH → KCl + HOH
C. HCN + KOH → KCN + HOH
pH
Volume 1.0 M NH3 added
14
7
0
0 30 60
Bisect the verticlepH = 9
6. Match the Curve with the Reaction
A. 3HCl + Al(OH)2 → AlCl3 + 3HOH
B. HCl + KOH → KCl + HOH
C. HCN + KOH → KCN + HOH
pH
Volume 1.0 M NH3 added
14
7
0
0 30 60
Bisect the verticlepH = 9
6. Match the Curve with the Reaction
