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49Chapter 5Acids, Bases, and Acid-Base Reactions Review Skills5.1 Acids Arrhenius Acids Types of Arrhenius Acids Strong and Weak AcidsSpecial Topic 5.1: Acid RainInternet: Acid Animation5.2 Acid Nomenclature Names and Formulas of BinaryAcids Names and Formulas ofOxyacids5.3 Summary of Chemical NomenclatureInternet: Types of SubstancesInternet: Chemical Nomenclature5.4 Strong and Weak Arrhenius BasesSpecial Topic 5.2: Chemicalsand Your Sense of TasteInternet: Strong and Weak BasesInternet: Identification ofStrong and Weak Acids andBases5.5 pH and Acidic and Basic Solutions5.6 Arrhenius Acid-Base Reactions Reactions of Aqueous StrongArrhenius Acids and AqueousStrong Arrhenius Bases Writing Equations for ReactionsBetween Acids and BasesSpecial Topic 5.3: Precipitation,Acid-Base Reactions, and ToothDecay Reactions of Arrhenius Acids andIonic Compounds That ContainCarbonate or Hydrogen CarbonateSpecial Topic 5.4: Saving ValuableBooksSpecial Topic 5.5: Be Careful withBleachInternet: Acid-Base ReactionAnimation5.7 Brønsted-Lowry Acids and Bases Chapter GlossaryInternet: Glossary Quiz Chapter ObjectivesReview QuestionsKey IdeasChapter Problems

50Study Guide for An Introduction to ChemistrySection Goals and IntroductionsSection 5.1 AcidsGoals To describe acids To make the distinction between strong and weak acids. To show the changes that take place on the particle level when acids dissolve in water. To show how you can recognize strong and weak acids.This section introduces one way to define acids, called the Arrhenius definition. The mostimportant skills to develop in this section are (1) to be able to recognize acids from names orformulas and (2) to be able to describe the changes that take place at the particle level whenstrong and weak acids dissolve in water. Be sure to give special attention to Figures 5.1, 5.5,and 5.6. Visit our Web site to view an animation that illustrates the differences between strongand weak acids:Internet: Acid AnimationSection 5.2 Acid Nomenclature Goal: To describe how to convert between names and chemical formulas for acids.This section adds acids to the list of compounds for which you should be able to convertbetween names and formulas.Section 5.3 Summary of Chemical Nomenclature Goal: To review the process for converting between names and formulas for binarycovalent compounds, binary ionic compounds, ionic compounds with polyatomic ions,binary acids, and oxyacids.Although chemical nomenclature may not be your favorite topic, it is an important one. Theability to convert among names and formulas for chemical compounds is crucial tocommunication between chemists and chemistry students. This section collects thenomenclature guidelines from Chapters 3 and 5 and gives you a chance to review them. Table5.6 provides your most concise summary of these guidelines. Our Web site provides tutorialsthat allow you to practice identifying types of substances and converting between names andformulas for chemical compounds:Internet: Types of SubstancesInternet: Chemical NomenclatureSection 5.4 Strong and Weak Arrhenius BasesGoals To describe bases and to make the distinction between strong and weak bases. To show how you can recognize strong and weak bases. To show the changes that take place on the particle level when bases dissolve in water.This section does for bases what Section 5.1 does for acids: (1) it states the Arrheniusdefinition of base, (2) it provides you with the information necessary to identify strong andweak bases, and (3) it describes the changes that take place when one weak base (ammonia)dissolves in water (Figure 5.8). Sample Study Sheet 5.1 summarizes the steps for identification

Chapter 5 – Acids, Bases, and Acid-Base Reactions51of strong and weak acids and bases. Visit our Web site for more information about strong andweak bases and the identification of strong and weak acids and bases.Internet: Strong and Weak BasesInternet: Identification of Strong and Weak Acids and BasesSection 5.5 pH and Acidic and Basic SolutionsGoal: To explain the pH scale used to describe acidic and basic solutions.This section provides an introduction to the pH scale used to describe acidic and basicsolutions. Figure 5.10 contains the most important information.Section 5.6 Arrhenius Acid-Base ReactionsGoals To describe acid-base reactions, with an emphasis on developing the ability to visualizethe changes that take place on the particle level. To show how you can predict whether two reactants will react in an acid-base reaction. To show how to write equations for acid-base reactions.This section does for acid-base reactions what Section 4.2 does for precipitation reactions. Itmight help to consider the similarities and differences between these two types of chemicalchanges. Be sure that you can visualize the changes that take place at the particle level forboth types of chemical reactions. Pay special attention to Figures 5.12, 5.13, and 5.15. Visitour Web site to see an animation showing an acid-base reaction.Internet: Acid-Base Reaction AnimationSection 5.7 Brønsted-Lowry Acids and BasesGoal: To describe a second set of definitions for acid, base, and acid-base reactions, calledthe Brønsted-Lowry definitions.Although the Arrhenius definitions of acid, base, and acid-base reactions provided in Sections5.1, 5.4, and 5.6 are very important, especially to the beginning chemistry student, chemistshave found it useful to extend these definitions to include new substances as acids and basesthat would not be classified as such according to the Arrhenius definitions. The newdefinitions, called the Brønsted-Lowry definitions, are described in this section.

52Study Guide for An Introduction to ChemistryChapter 5 MapChapter ChecklistRead the Review Skills section. If there is any skill mentioned that you have not yetmastered, review the material on that topic before reading this chapter.Read the chapter quickly before the lecture that describes it.Attend class meetings, take notes, and participate in class discussions.Work the Chapter Exercises, perhaps using the Chapter Examples as guides.Study the Chapter Glossary and test yourself on our Web site:Internet: Glossary QuizStudy all of the Chapter Objectives. You might want to write a description of how youwill meet each objective. (Although it is best to master all of the objectives, the following

Chapter 5 – Acids, Bases, and Acid-Base Reactions53objectives are especially important because they pertain to skills that you will need whilestudying other chapters of this text: 13, 14, 18-21, and 24.)Reread Sample Study Sheet 5.1: Identification of Strong and Weak Acids and Bases anddecide whether you will use it or some variation on it to complete the task it describes.Memorize the following. Be sure to check with your instructor to determine how muchyou are expected to know of the following. Guidelines for writing names and formulas for compoundsType ofcompoundGeneral formulaExamplesGeneral nameExamplesBinarycovalentSection 3.4AaBbN2O5or CO2(prefix unless mono)(name of first element informula) (prefix)(root of second element)idedinitrogen pentoxideor carbon dioxideBinary ionicSection 3.5MaAbNaClor FeCl3(name of metal) (root of nonmetal)ideor (name of metal)(Roman ) (root ofnonmetal)idesodium chlorideor iron(III) chlorideIonic withpolyatomicion(s)Section 3.5MaXb or (NH4)aXbX recognizedformula ofpolyatomic ionLi2HPO4or CuSO4or NH4Clor(NH4)2SO4(name of metal) (name of polyatomic ion)or (name of metal)(Roman ) (name ofpolyatomic ion) or ammonium (root ofnonmetal)ideor ammonium (name of polyatomic ion)lithium hydrogenphosphateor copper(II) sulfateor ammonium chlorideor ammonium sulfateBinary acidSection 5.2HX(aq)HCl(aq)hydro(root)ic acidhydrochloric acidHNO3or H2SO4or H3PO4(root)ic acidnitric acidor sulfuric acidor phosphoric acidOxyacidSection 5.2HaXbOcNotes: M symbol of metalA and B symbols of nonmetalsX some element other than H or Oa, b, & c indicate subscripts The significance of the numbers in the pH scale

54Study Guide for An Introduction to ChemistryTo get a review of the most important topics in the chapter, fill in the blanks in the KeyIdeas section.Work all of the selected problems at the end of the chapter, and check your answers withthe solutions provided in this chapter of the study guide.Ask for help if you need it.Web ResourcesInternet: Acid AnimationInternet: Types of SubstancesInternet: Chemical NomenclatureInternet: Strong and Weak BasesInternet: Identification of Strong and Weak Acids and BasesInternet: Acid-Base ReactionInternet: Glossary QuizExercises KeyExercise 5.1 - Formulas for Acids: Write the chemical formulas that correspond to thenames (Obj 12)(a) hydrofluoric acidThis name has the form of a binary acid, hydro(root)ic acid, so its formula isHF(aq).(b) phosphoric acidThis name has the form of an oxyacid, (root)ic acid, so it contains hydrogen,phosphorus, and oxygen. Phosphate is PO43 , so phosphoric acid is H3PO4.Exercise 5.2 - Naming Acids: Write the names that correspond to the chemical formulas(Obj 12)(a) HI(aq)This is a binary acid, so its name has the form hydro(root)ic acid. HI(aq) ishydriodic acid. (The “o” in hydro- is usually left off.)(b) HC2H3O2.The name of the oxyanion C2H3O2– is acetate, so HC2H3O2 is acetic acid.CH3CO2H and CH3COOH are also commonly used as formulas for acetic acid.Exercise 5.3 - Formulas to Names: Write the names that correspond to the followingchemical formulas. (Obj 14)a. AlF3aluminum fluoridef. CuCl2copper(II) chlorideb. PF3phosphorus trifluorideg. NH4Fammonium fluoridec. H3PO4phosphoric acidh. HCl(aq)hydrochloric acidd. CaCO3calcium carbonatei. (NH4)3PO4ammonium phosphatee. Ca(HSO4)2calcium hydrogen sulfate

Chapter 5 – Acids, Bases, and Acid-Base Reactions55Exercise 5.4 - Names to Formulas: Write the chemical formulas that correspond to thefollowing names. (Obj 14)a.b.c.d.e.ammonium nitrateNH4NO3acetic acidHC2H3O2sodium hydrogen sulfate NaHSO4potassium bromideKBrmagnesium hydrogen phosphateMgHPO4f.g.h.i.hydrofluoric aciddiphosphorus tetroxidealuminum carbonatesulfuric acidHF(aq)P2O4Al2(CO3)3H2SO4Exercise 5.5 - Identification of Acids and Bases: Identify each of the following as anArrhenius strong acid, an Arrhenius weak acid, an Arrhenius strong base, or an Arrhenius weakbase. (Obj 18)a. HNO3strong acidc. K2CO3weak baseb. lithium hydroxide strong based. hydrofluoric acid weak acidExercise 5.6 - Neutralization Reactions: Write the complete equation for theneutralization reactions that take place when the following water solutions are mixed. (If an acidhas more than one acidic hydrogen, assume that there is enough base to remove all of them.Assume that there is enough acid to neutralize all of the basic hydroxide ions.) (Obj 24)a. HCl(aq) NaOH(aq) H2O(l) NaCl(aq)b. HF(aq) LiOH(aq) H2O(l) LiF(aq)c. H3PO4(aq) 3LiOH(aq) 3H2O(l) Li3PO4(aq)d. Fe(OH)3(s) 3HNO3(aq) Fe(NO3)3(aq) 3H2O(l)Exercise 5.7 - Neutralization Reactions with Compounds Containing Carbonate:Write the complete equation for the neutralization reaction that takes place when water solutionsof sodium carbonate, Na2CO3, and hydrobromic acid, HBr, are mixed.(Obj 24)Na2CO3(aq) 2HBr(aq) 2NaBr(aq) H2O(l) CO2(g)Exercise 5.8 - Conjugate Acids: Write the formula for the conjugate acid of (a) NO2–, (b)HCO3–, (c) H2O, and (d) PO43–. (Obj 27)a. HNO2b. H2CO3c. H3O d. HPO42–Exercise 5.9 - Conjugate Bases: Write the formula for the conjugate base of (a) H2C2O4,(b) HBrO4, (c) NH3, and (d) H2PO4–. (Obj 28)a. HC2O4– b. BrO4– c. NH2– d. HPO42–Exercise 5.10 - Brønsted-Lowry Acids and Bases: Identify the Brønsted-Lowry acid andbase in each of the following equations. (Obj 31)a. HNO2(aq) NaBrO(aq) HBrO(aq) NaNO2(aq)B/L acidB/L base–b. H2AsO4 (aq) HNO2(aq)H3AsO4(aq) NO2–(aq)B/L baseB/L acid–c. H2AsO4 (aq) 2OH–(aq) AsO43–(aq) 2H2O(l)B/L acidB/L base

56Study Guide for An Introduction to ChemistryReview Questions Key1. Define the following terms.a. aqueousWater solutions are called aqueous solutions.b. spectator ionIons that are important for delivering other ions into solution to react, but do notactively participate in the reaction themselves are called spectator ions.c. double-displacement reactionA chemical reaction that has the following form is called a double-displacementreaction.AB CD AD CBd. net ionic equationA net ionic equation is a chemical equation for which the spectator ions havebeen eliminated leaving only the substances actively involved in the reaction.2. Write the name of the polyatomic ions represented by the formulas CO32– and HCO3–.a. CO32– carbonateb. HCO3– hydrogen carbonate3. Write the formulas for the polyatomic ions dihydrogen phosphate ion and acetate ion.a. dihydrogen phosphate ion H2PO4–b. acetate ion C2H3O2–4. Which of the following formulas represents an ionic compound?d. Na2SO4 ionica. MgCl2 ionicb. PCl3not ionice. H2SO4 not ionicc. KHSO4 ionic5. Write the names that correspond to the formulas KBr, Cu(NO3)2, and (NH4)2HPO4.c. (NH4)2HPO4 ammonium hydrogena. KBr potassium bromideb. Cu(NO3)2 copper(II) nitratephosphate6. Write the formulas that correspond to the names nickel(II) hydroxide, ammonium chloride,and calcium hydrogen carbonate.c. calcium hydrogen carbonatea. nickel(II) hydroxide Ni(OH)2b. ammonium chloride NH4ClCa(HCO3)27. Predict whether each of the following is soluble or insoluble in water.a. iron(III) hydroxide insolublec. aluminum nitrate solubleb. barium sulfateinsolubled. copper(II) chloride soluble8. Describe the process by which the ionic compound sodium hydroxide dissolves in water.When solid sodium hydroxide, NaOH, is added to water, all of the sodium ions, Na , andhydroxide ions, OH–, at the surface of the solid can be viewed as shifting back and forthbetween moving out into the water and returning to the solid surface. Sometimes when anion moves out into the water, a water molecule collides with it, helping to break the io