1. Titration with multi-protic acids and multi-hydroxy bases
Spring 2008

2. Neutralization means equal amounts of H+ ions are balanced by OH- ions
Mononprotic acids have 1 H+
Monohydroxy bases have 1 OH-
The actual molarity of these acids or bases is equal to the Molarity of the solution on the label. [multiply the strength x the number of ions in the formula]
2 M HCl has 2 Moles/L x 1 H+ = 2Moles H+ ions
5 M HF has 5 Moles/L x 1 H+ = 5 Moles H+ ions

3. Diprotic Acids and Dihdyroxy Bases
Di- means 2
H2SO4 is a diprotic acid Ba(OH)2 is a dihydroxy base
The strength of these solutions is greater than a monoprotic or monohydroxy substance
2M H2SO4 really is like a 4Molar solution
2 Moles/Liter x 2 H+ = 4 Moles of H+ ions
3M Ca(OH)2 is really like a 6 Molar solution
3 Moles/Liter x 2 OH- = 6 Moles of OH- ions

4. Triprotic Acids and Trihdyroxy Bases
Tri- means _____
___________is a triprotic acid __________ is a trihydroxy base
The strength of these solutions is greater than a monoprotic or monohydroxy substance
2M H3PO4 really is like a _____Molar solution
2 Moles/Liter x ____ H+ = ___ Moles of H+ ions
3M ____(OH)3 is really like a ____Molar solution
3 Moles/Liter x ____ OH- = ____ Moles of OH- ions

5. Solving Tricky Titration Problems
Remember to multiply the number of H or OH ions in the acid or base formula by the strength of the solution
Example: 20 ml of 2.0 M H2SO4 are needed to neutralize what volume of a 1M NaOH solution?
Ma = 2.0Moles/L x 2 H+ ions = 4.0 Moles H+ ions Va= 20ml
Mb = 1Mole/L x 1 OH- ion = 1 mole OH- ions
Ma x Va = Mb x Vb
(4 moles H+) ( 20 ml) = (1 mole OH-) ( Vb)
80 ml = Vb

6. 50 ml of 2 M H3 PO4 is neutralized by how much of 2M Ca(OH)2?
2M x 3 H+ = 6 M H+ = Ma
2M x 2 OH- = 4M OH- = Mb
Ma x Va = Mb x Vb
___________________________
____________________________
Read carefully and check your answer.
What is the name of the salt produced? What is its formula? What is the pH of the solution produced?

7. Review Material: Fill in with words, phrases, number phrases,etc.
If [H+] > [OH-] the pH is _____________ and the solution is __________.
If [H+] < [OH-] the pH is _____________ and the solution is __________.
If [H+] = [OH-] the pH is _____________ and the solution is __________.
pH of 3 means the [H+] =____________ and the [OH-] is _____________.
pH of 12 means the [H+] =____________ and the [OH-] is _____________.