1. Chem 105 Chpt 4 Lsn 12 1 CHAPTER 5 Reactions in Aqueous Solution Homework for Chapter 5 problems posted due Feb 26 Know: Table 5.2, pg 182 Use: Figure 5.3, page 179 Homework for Chapter 5 problems posted due Feb 26 Know: Table 5.2, pg 182 Use: Figure 5.3, page 179

2. Chem 105 Chpt 4 Lsn 12 2 Road Map Where we were Where we were Total & Net ionic equations Total & Net ionic equations Acids and bases Acids and bases Precipitation reactions Precipitation reactions Where we are going Where we are going Classifying reactions Classifying reactions Oxidation reactions Oxidation reactions Measuring concentrations of compounds in solution Measuring concentrations of compounds in solution pH pH Stoichiometry of reactions in aqueous solution Stoichiometry of reactions in aqueous solution

3. Chem 105 Chpt 4 Lsn 12 3 Practice Problem 10 - 4 Calcium chloride and potassium phosphate combine to form calcium phosphate and potassium chloride. Write the molecular equation 3 CaCl 2 (aq) + 2 K 3 PO 4 (aq) → Ca 3 PO 4 (s) + 6 KCl(aq) Write the Total Ionic and Net Ionic equations

4. Chem 105 Chpt 4 Lsn 12 4 3 CaCl 2 (aq) + 2 K 3 PO 4 (aq) → Ca 3 PO 4 (s) + 6 KCl(aq) Write the Total Ionic and Net Ionic equations Combining 5 grams CaCl 2 with 3.5 grams of K 3 PO 4 produced only a 67% yield of KCl. What is the limiting reactant? What mass of product did you make?

5. Chem 105 Chpt 4 Lsn 12 5 5.4 Acid-Base Reactions: Acid-Base Titrations What volume of 0.1292 M Ba(OH) 2 would neutralize 50.00 mL of the HCl solution standardized in the preceding sample problem (4.5) ?

6. Chem 105 Chpt 4 Lsn 12 6 Classifying reactions (5-29) Balance the following reactions (  √) and then classify each as precipitation, acid- base, or gas-forming reaction. Balance the following reactions (  √) and then classify each as precipitation, acid- base, or gas-forming reaction. a) Ba(OH) 2 (aq) + 2 HCl (aq)  BaCl 2 (aq) + 2 H 2 O (l) a) Ba(OH) 2 (aq) + 2 HCl (aq)  BaCl 2 (aq) + 2 H 2 O (l) b) 2 HNO 3 (aq) + CoCO 3 (s)  Co(NO 3 ) 2 (aq) + H 2 O (l) + CO 2 (g) b) 2 HNO 3 (aq) + CoCO 3 (s)  Co(NO 3 ) 2 (aq) + H 2 O (l) + CO 2 (g) c) 2 Na 3 PO 4 (aq) + 3 Cu(NO 3 ) 2 (aq)  Cu 3 (PO 4 ) 2 (s) + 6 NaNO 3 (aq) c) 2 Na 3 PO 4 (aq) + 3 Cu(NO 3 ) 2 (aq)  Cu 3 (PO 4 ) 2 (s) + 6 NaNO 3 (aq)

7. Chem 105 Chpt 4 Lsn 12 7 Oxidation Numbers ReDox Reactions 5-36 (pg 225) Oxidation number 5-36 (pg 225) Oxidation number PF 6 - H 2 AsO 4 - UO 2 - N 2 O 5 POCl 5 XeO 4 2- PF 6 - H 2 AsO 4 - UO 2 - N 2 O 5 POCl 5 XeO 4 2- 5-37 (a) 5-37 (a) Zn (s)  Zn 2+ (aq)0  2 + (ox) Zn (s)  Zn 2+ (aq)0  2 + (ox) N 5+  N 4+ (aq)5 +  4 + (red) N 5+  N 4+ (aq)5 +  4 + (red) O 2-  O 2- (aq)no change O 2-  O 2- (aq)no change H +  H + (aq)no change H +  H + (aq)no change Oxidation (loss of e - ) Oxidation (loss of e - ) Reduction (gain of e - ) Reduction (gain of e - )

8. Chem 105 Chpt 4 Lsn 12 8 5.8 Measuring Concentrations How many moles of H + (aq) are present in 451 mL of 3.20 M hydrobromic acid? 5-46 What volume 2.06 M KMnO 4, in liters, contains 322 g of solute? 0.989 L

9. Chem 105 Chpt 4 Lsn 12 9 Preparing solutions 5-50 What mass of oxalic acid, H 2 C 2 O 4, is required to prepare 250. mL of a solution that has a concentration or 0.15 M H 2 C 2 O 4 ? 5-50 What mass of oxalic acid, H 2 C 2 O 4, is required to prepare 250. mL of a solution that has a concentration or 0.15 M H 2 C 2 O 4 ? 3.4 g H 2 C 2 O 4 3.4 g H 2 C 2 O 4

10. Chem 105 Chpt 4 Lsn 12 10 pH pH = -log [H + ] pH = -log [H + ] pOH = - log [OH - ] pOH = - log [OH - ] K w = [H + ][OH - ] = 1.00 x 10 -14 K w = [H + ][OH - ] = 1.00 x 10 -14 pH + pOH = 14 pH + pOH = 14 5-56 A saturated solution of milk of magnesia, Mg(OH) 2, has a pH of 10.5. What is the hydrogen ion concentration of the solution? Is the solution acidic or basic? 5-56 A saturated solution of milk of magnesia, Mg(OH) 2, has a pH of 10.5. What is the hydrogen ion concentration of the solution? Is the solution acidic or basic?

11. Chem 105 Chpt 4 Lsn 12 11 Stoichiometry of Reactions in Solution 5-64 Hydrazine, N 2 H 4, a base like ammonia, can react with an acid such as sulfuric acid. What mass of hydrazine reacts with 250. mL of 0.146 M H 2 SO 4 ? 5-64 Hydrazine, N 2 H 4, a base like ammonia, can react with an acid such as sulfuric acid. What mass of hydrazine reacts with 250. mL of 0.146 M H 2 SO 4 ? 2 N 2 H 4 (aq) + H 2 SO 4 (aq)  2 N 2 H 5 + (aq) + SO 4 2- (aq) 2.34 g N 2 H 4 2.34 g N 2 H 4

12. Chem 105 Chpt 4 Lsn 12 12 Challenge 5- 75 5- 75 5- 74 5- 74

13. Chem 105 Chpt 4 Lsn 12 13 Next Lesson Chapter 6 Chapter 6