Acid/Base and Redox Reactions Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 1/2

Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 4/3 Acids, Bases, and Neutralization Reactions H 3 O 1+ (aq) + Cl 1- (aq)HCl(aq) + H 2 O(aq) Acid (Arrhenius): A substance that dissociates in water to produce hydrogen ions, H 1+ : H 1+ (aq) + A 1- (aq)HA(aq) In water, acids produce hydronium ions, H 3 O 1+ : H 1+ (aq) + Cl 1- (aq)HCl(aq)

Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 4/4 Acids, Bases, and Neutralization Reactions Ammonia, commonly called “ammonium hydroxide” is a base: M 1+ (aq) + OH 1- (aq)MOH(aq) Na 1+ (aq) + OH 1- (aq)NaOH(aq) NH 4 1+ (aq) + OH 1- (aq)NH 3 (aq) + H 2 O(aq) Base (Arrhenius): A substance that dissociates in water to produce hydroxide ions, OH 1- :

Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 4/5 Acids, Bases, and Neutralization Reactions Weak acids and weak bases are weak electrolytes. Strong acids and strong bases are strong electrolytes.

Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 4/6 Acids, Bases, and Neutralization Reactions MA + H 2 OHA + MOH These acid-base neutralization reactions are double- replacement reactions just like the precipitation reactions: or MA + HOHHA + MOH WaterAcidBaseSalt

Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 4/7 Write the chemical formulas of the products (use proper ionic rules for the salt). 1. Acids, Bases, and Neutralization Reactions Write the molecular, ionic, and net ionic equations for the reaction of aqueous HBr and aqueous Ba(OH) 2. H2OH2OHBr(aq)+Ba(OH) 2 (aq)+BaBr 2 SaltAcidBaseWater

Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 4/8 Molecular Equation: Balance the equation and predict the solubility of the salt in the products. 2. Acids, Bases, and Neutralization Reactions Write the molecular, ionic, and net ionic equations for the reaction of aqueous HBr and aqueous Ba(OH) 2. 2H 2 O(l) + BaBr 2 (aq)2HBr(aq) + Ba(OH) 2 (aq) Use the solubility rules.

Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 4/9 Ionic Equation: Dissociate a strong acid and the soluble ionic compounds. 3. Acids, Bases, and Neutralization Reactions Write the molecular, ionic, and net ionic equations for the reaction of aqueous HBr and aqueous Ba(OH) 2. 2H 2 O(l) + Ba 2+ (aq) + 2Br 1- (aq) 2H 1+ (aq) + 2Br 1- (aq) + Ba 2+ (aq) + 2OH 1- (aq) BaBr 2 (aq) 2HBr(aq)Ba(OH) 2 (aq)

Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 4/10 2H 2 O(l) + Ba 2+ (aq) + 2Br 1- (aq) Acids, Bases, and Neutralization Reactions Write the molecular, ionic, and net ionic equations for the reaction of aqueous HBr and aqueous Ba(OH) 2. Net Ionic Equation: Eliminate the spectator ions from the ionic equation. 4. 2H 1+ (aq) + 2Br 1- (aq) + Ba 2+ (aq) + 2OH 1- (aq) or H 2 O(l)H 1+ (aq) + OH 1- (aq) 2H 2 O(l)2H 1+ (aq) + 2OH 1- (aq)

Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 4/11 Acids, Bases, and Neutralization Reactions Write the molecular, ionic, and net ionic equations for the reaction of aqueous NaOH and aqueous HF. Write the chemical formulas of the products (use proper ionic rules for the salt). 1. SaltAcidBaseWater H2OH2OHF(aq) + NaOH(aq)+NaF

Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 4/12 Acids, Bases, and Neutralization Reactions Write the molecular, ionic, and net ionic equations for the reaction of aqueous NaOH and aqueous HF. Molecular Equation: Balance the equation and predict the solubility of the salt in the products. 2. H 2 O(l) + NaF(aq)HF(aq) + NaOH(aq) Use the solubility rules.

Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 4/13 Acids, Bases, and Neutralization Reactions Write the molecular, ionic, and net ionic equations for the reaction of aqueous NaOH and aqueous HF. Ionic Equation: Dissociate a strong acid and the soluble ionic compounds. 3. H 2 O(l) + Na 1+ (aq) + F 1- (aq)HF(aq) + Na 1+ (aq) + OH 1- (aq) NaF(aq) NaOH(aq)

Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 4/14 Acids, Bases, and Neutralization Reactions Write the molecular, ionic, and net ionic equations for the reaction of aqueous NaOH and aqueous HF. Net Ionic Equation: Eliminate the spectator ions from the ionic equation. 4. H 2 O(l) + Na 1+ (aq) + F 1- (aq)HF(aq) + Na 1+ (aq) + OH 1- (aq) H 2 O(l) + F 1- (aq)HF(aq) + OH 1- (aq)

Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 4/15 Oxidation-Reduction (Redox) Reactions 2Fe 2 O 3 (s)4Fe(s) + 3O 2 (g) Rusting of iron: an oxidation of Fe 4Fe(s) + 3CO 2 (g)2Fe 2 O 3 (s) + 3C(s) Manufacture of iron: a reduction of Fe

Aqueous potassium permanganate

Magnesium metal

Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 4/18 Oxidation-Reduction (Redox) Reactions 1.An atom in its elemental state has an oxidation number of 0. Rules for Assigning Oxidation Numbers Oxidation Number (State): A value which indicates whether an atom is neutral, electron-rich, or electron- poor. NaH2H2 Br 2 SNe Oxidation number 0 Page 118

Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 4/19 Oxidation-Reduction (Redox) Reactions 2.A monatomic ion has an oxidation number identical to its charge. Na Ca Al Cl 1- O 2- -2

Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 4/20 Oxidation-Reduction (Redox) Reactions b)Oxygen usually has an oxidation number of -2. HO HHCa +2 3.An atom in a polyatomic ion or in a molecular compound usually has the same oxidation number it would have if it were a monatomic ion. a)Hydrogen can be either +1 or -1. OHO +1 HHO H +1

Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 4/21 Oxidation-Reduction (Redox) Reactions HCl +1 c)Halogens usually have an oxidation number of Cl O +1 -2

Copyright © 2008 Pearson Prentice Hall, Inc.Chapter 4/22 Oxidation-Reduction (Redox) Reactions Cr 2 O x 4.The sum of the oxidation numbers is 0 for a neutral compound and is equal to the net charge for a polyatomic ion. x = +6 2(x) + 7(-2) = -2 (net charge) H2SO3H2SO3 x-2 x = +4 2(+1) + x + 3(-2) = 0 (net charge)

H15 – C4 4.9 – 4.11, 4.27*, 4.57, 4.59, 4.63*, 4.65*, 4.101*