1. Titrations
- Controlled addition and measurement of the amount of a solution of known concentration that is required to react with a measured amount of a solution of unknown concentration.

2. Important Terms and Concepts
Standard solution –
solution of known concentration.
Indicators –
weak acid or weak base dyes that are sensitive to pH (hydronium ion concentration).
Equivalence point –
The point at which the two solutions used in a titration are present in chemically equivalent amounts.
For our purposes, H3O+ = OH-
(moles of Acid = moles of Base)

3. Review
How many moles of cesium hydroxide are needed to react with excess magnesium phosphide to form 35.8 grams of cesium phosphide?
___ CsOH + ___ Mg3P2 → ___ Mg(OH) ___ Cs3P

4. Review
Calculate the molarity of a solution prepared by dissolving 5.64 grams of (NH4)2SO4 in enough water to produce 80.0mL of solution.
What volume of 1.6 M nitric acid solution can be made with 66.0 grams of HNO3?

5. Neutralization
Main Idea: Acids react with bases to produce a salt and water.

6. Predicting Products
Example #1: phosphoric acid (H3PO4) reacts with magnesium hydroxide Mg(OH)2.
H3PO Mg(OH)2 →
Example #2: sulfuric acid reacts with lithium hydroxide

7. Practice Titration Problems
2 HCl + Ba(OH)2  BaCl H2O
1) It requires 27.4mL of a standard solution of M Ba(OH)2 to completely neutralize 20.0mL of an HCl solution. Find the molarity of the acid.
Known Solution
Unknown Solution
Start bridge with volume of known solution.

8. Practice Titration Problems
2 KOH + H2SO4  K2SO H2O
2) What volume of 1.25M potassium hydroxide is required to neutralize 25.0mL of 12.0M sulfuric acid?
Known Solution
Unknown Solution
Start bridge with volume of known solution.

9. Practice Titration Problems
H2SO LiOH  Li2SO H2O
3) 17.6mL of H2SO4 is neutralized by 30.6 mL of M LiOH solution. Find the molarity of the acid.
Known Solution
Unknown Solution
Start bridge with volume of known solution.

10. Practice Titration Problems
1) It requires 27.4mL of a standard solution of M Ba(OH)2 to completely neutralize 20.0mL of an HCl solution. Find the molarity of the acid.
Since we are switching substances:
STOICHIOMETRY!!!!
mol HCl
LAcid ?
27.4mL Base
= L Base
Mole-to-mole using balanced equation!
0.0154mol Ba(OH)2
LBase
2 HCl + Ba(OH)2  BaCl H2O
Start bridge with volume of known solution.
20.0mL Acid
= L Acid
0.0274L Base
mol Ba(OH)2
2 mol HCl 
1 LBase
1 mol Ba(OH)2
0.0200LAcid
= M HCl

11. Practice Titration Problems
2) What volume of 1.25M potassium hydroxide is required to neutralize 25.0mL of 12.0M sulfuric acid?
12.0 mol H2SO4 L
Known Solution
25.0mL
= L
0.600mol
1.25 =
Unknown Solution
1.25 M KOH X
Mole-to-mole using balanced equation!
2 KOH + H2SO4  K2SO H2O
0.0250L H2SO4
12.0 mol H2SO4
2 mol KOH
1 L
1 mol H2SO4
= L or mL KOH
Start bridge with volume of known solution.

12. Practice Titration Problems
3) 17.6mL of H2SO4 is neutralized by 30.6 mL of M LiOH solution. Find the molarity of the acid.
30.6 mL LiOH
= L LiOH
Known Solution
mol LiOH L
mol
Unknown Solution
17.6 mL H2SO4
= L H2SO4
0.0176L
H2SO LiOH  Li2SO H2O
Mole-to-mole using balanced equation!
M H2SO4
L LiOH
mol LiOH
1 mol H2SO4
2 mol LiOH
1 L
Start bridge with volume of known solution.