Example 1 How many mL of 0.200 M NaOH will completely neutralize 100 mL 0.250 M H2SO4?

Example 2 If 40.0 mL of 1.60 M HCl and 60.0 mL of 2.00 M NaOH are mixed, what are the molar concentrations of Na+, Cl–, and OH– in the resulting solution?

Example 3 If 100. mL of 1.00 M H3PO4 solution is mixed with 200. mL of 1.00 M NaOH, what salt is produced, and what is its molarity?

Example 4 – Titration What is the molarity of NaOH solution if 92.0 mL of this solution was completely neutralized with 138 mL of 0.4 M H2SO4 solution?

Example 5 – Back Titration 74.5 ml of 2.61 M sodium hydroxide is added to 99.2 ml of acetic acid, and the resulting solution is found to be basic. It required 12.7 ml of 1.25 M sulfuric acid to reach neutrality. What is the molarity of the original acetic acid solution?

Example 5 (continued)

Example 6 – Titration The acidic substance in vinegar is acetic acid, HC2H3O2. When 6.00 g of a certain vinegar was titrated with 0.100 M NaOH, 40.11 mL of base had to be added to reach the equivalence point. What percent by mass of this sample of vinegar is acetic acid?

Eqivalent Weight Examples: One equivalent weight, or equivalent, of acid contains 1 mol of hydrogen ions One equivalent weight, or equivalent, of base contains 1 mol of hydroxide ions Examples: NaOH Ba(OH)2 HCl H2SO4

Normality

Example 7 666 g of Ba(OH)2 is dissolved in 3 L of water. Calculate the normality of the solution.

Example 8 Calculate the normality of a solution of H3PO4 if 500 mL of the solution react completely with 30 g of NaOH.

Normality The neutralization (acid-base) reaction can typically be presented by the net ionic equation: H+ + OH–  H2O Therefore, one equivalent of acid always reacts with one equivalent of base, and vice versa: # equivs. acid = # equivs. base Vacid × Nacid = Vbase × Nbase

Example 9 What volume of 3.00N solution of H3PO4 will react completely with 750 ml of 2.00N solution of Ba(OH)2?

Assignments & Reminders Read Chapter 11 completely Read Section 4-7 of Chapter 4 Extra Review Session – 5 to 7 pm on Thursday in 105 Heldenfels Review Session for Exam #3 – 5:15 to 7:15 pm on Sunday in 100 Heldenfels