General, Organic, and Biological Chemistry Fourth Edition Karen Timberlake 10.1 Acids and Bases Chapter 10 Acids and Bases © 2013 Pearson Education, Inc. Lectures

© 2013 Pearson Education, Inc. Chapter 10, Section 1 2 Arrhenius Acids Arrhenius acids  produce H + ions in water. H 2 O  have a sour taste.  turn blue litmus paper red.  corrode some metals. Citrus fruits are sour because of the presence of acids.

© 2013 Pearson Education, Inc. Chapter 10, Section 1 3 Naming Acids  Acids with H and a nonmetal are named with the prefix hydro− and end with −ic acid. HClhydrochloric acid  Acids with H and an oxygen-containing polyatomic ion are named by changing the end of the name of the polyatomic ion from −ate to −ic acid or −ite to −ous acid. ClO 3 − chlorate HClO 3 chloric acid ClO 2 − chlorite HClO 2 chlorous acid

© 2013 Pearson Education, Inc. Chapter 10, Section 1 4 Naming Some Common Acids

© 2013 Pearson Education, Inc. Chapter 10, Section 1 5 Select the correct name for each of the following acids. 1. HBr A. bromic acid B. bromous acid C. hydrobromic acid 2. H 2 CO 3 A. carbonic acid B. hydrocarbonic acid C. carbonous acid 3. HBrO 2 A. bromic acid B. hydrobromous acid C. bromous acid Learning Check

© 2013 Pearson Education, Inc. Chapter 10, Section HBrC. hydrobromic acid The name of an acid with H and one nonmetal uses the prefix hydro− and ends with −ic acid. 2. H 2 CO 3 A. carbonic acid An acid with H and a polyatomic ion, bicarbonate, HCO 3 − is named by changing the end of the ion’s name from −ate to −ic acid. 3. HBrO 2 C. bromous acid This acid of bromite, (BrO 2 − ) is bromous acid. Solution

© 2013 Pearson Education, Inc. Chapter 10, Section 1 7 Bases Arrhenius bases  produce OH − ions in water.  taste bitter or chalky.  feel soapy and slippery.  turn red litmus paper blue.  turn the phenolphthalein indicator pink.

© 2013 Pearson Education, Inc. Chapter 10, Section 1 8 Some Common Bases Bases with OH  ions are named as the hydroxide of the metal in the formula. NaOHsodium hydroxide KOHpotassium hydroxide Ba(OH) 2 barium hydroxide Al(OH) 3 aluminum hydroxide Fe(OH) 3 iron (III) hydroxide

© 2013 Pearson Education, Inc. Chapter 10, Section 1 9 Base – Ca(OH) 2 Slaked Lime Calcium hydroxide, Ca(OH) 2, also called slaked lime, is used to produce beverages, neutralize acids, and in dentistry as a filler for root canals.

© 2013 Pearson Education, Inc. Chapter 10, Section 1 10 Match the formulas with the names. 1. HNO 2 A. iodic acid 2. Ca(OH) 2 B. sulfuric acid 3. H 2 SO 4 C. sodium hydroxide 4. HIO 3 D. nitrous acid 5. NaOHE. calcium hydroxide Learning Check

© 2013 Pearson Education, Inc. Chapter 10, Section 1 11 Match the formulas with the names. 1. HNO 2 D. nitrous acid 2. Ca(OH) 2 E. calcium hydroxide 3. H 2 SO 4 B. sulfuric acid 4. HIO 3 A. iodic acid 5. NaOHC. sodium hydroxide Solution

© 2013 Pearson Education, Inc. Chapter 10, Section 1 12 Comparing Acids and Bases

© 2013 Pearson Education, Inc. Chapter 10, Section 1 13 Identify each as a characteristic of an acid or base. ____ A. has a sour taste ____ B. produces OH − in aqueous solutions ____ C. has a bitter taste ____ D. is an electrolyte ____ E. produces H + in aqueous solutions Learning Check

© 2013 Pearson Education, Inc. Chapter 10, Section 1 14 Identify each as a characteristic of an acid or base. acid A. has a sour taste baseB. produces OH − in aqueous solutions base C. has a bitter taste acid and base D. is an electrolyte acid E. produces H + in aqueous solutions Solution

© 2013 Pearson Education, Inc. Chapter 10, Section 1 15 Brønsted – Lowry Acids According to the Brønsted–Lowry theory, acids donate a proton (H + ). In the reaction of hydrochloric acid and water,  HCl is the acid that donates H +, and  H 2 O is the base that accepts H +.

© 2013 Pearson Education, Inc. Chapter 10, Section 1 16 Brønsted – Lowry Bases According to the Brønsted–Lowry theory, bases accept a proton (H + ). In the reaction of ammonia and water,  NH 3 is the base that accepts H +, and  H 2 O is the acid that donates H +.

© 2013 Pearson Education, Inc. Chapter 10, Section 1 17 Conjugate Acid – Base Pairs In any acid–base reaction, there are two conjugate acid–base pairs.  Each is related by the loss and gain of H +.  One occurs in the forward direction.  One occurs in the reverse direction. conjugate acid–base pair 1 HA conjugate acid–base pair 2

© 2013 Pearson Education, Inc. Chapter 10, Section 1 18 Conjugate Acids and Bases, HF  The first conjugate acid–base pair is HF/F −. HF loses one H + to form its conjugate base F −.  The other conjugate acid–base pair is H 2 O/H 3 O +. H 2 O acts as a base accepting one H + to form its conjugate acid H 3 O +.

© 2013 Pearson Education, Inc. Chapter 10, Section 1 19 Conjugate Acids and Bases, NH 3  The first conjugate acid–base pair is NH 3 /NH 4 +. NH 3, acts as a base by gaining H + to form its conjugate acid NH 4 +.  The other conjugate acid–base pair is H 2 O/OH –. H 2 O acts as an acid by donating one H + to form its conjugate base OH −.

© 2013 Pearson Education, Inc. Chapter 10, Section 1 20 Learning Check 1. Write the conjugate base of the following. A. HBr B. H 2 S C. H 2 CO 3 2. Write the conjugate acid of the following. A. NO 2 − B. NH 3 C. OH −

© 2013 Pearson Education, Inc. Chapter 10, Section 1 21 Solution 1. Write the conjugate base of the following. Remove H + to write the conjugate base. A. HBrBr − B. H 2 SHS − C. H 2 CO 3 HCO 3 − 2. Write the conjugate acid of the following. Add H + to write the conjugate acid. A. NO 2 − HNO 2 B. NH 3 NH 4 + C. OH − H 2 O

© 2013 Pearson Education, Inc. Chapter 10, Section 1 22 Learning Check Identify the sets that contain acid–base conjugate pairs. A. HNO 2, NO 2 − B. H 2 CO 3, CO 3 2− C. HCl, ClO 4 − D. HS −, H 2 S E. NH 3, NH 4 +

© 2013 Pearson Education, Inc. Chapter 10, Section 1 23 Solution Identify the sets that contain acid–base conjugate pairs. A. HNO 2, NO 2 − D. HS −, H 2 S E. NH 3, NH 4 +

© 2013 Pearson Education, Inc. Chapter 10, Section 1 24 Learning Check 1. The conjugate base of HCO 3 − is A. CO 3 2−. B. HCO 3 −. C. H 2 CO The conjugate acid of HCO 3 − is A. CO 3 2−. B. HCO 3 −. C. H 2 CO The conjugate base of H 2 O is A. OH −. B. H 2 O. C. H 3 O The conjugate acid of H 2 O is A. OH −. B. H 2 O. C. H 3 O +.

© 2013 Pearson Education, Inc. Chapter 10, Section 1 25 Solution 1. (A) The conjugate base of HCO 3 − is, CO 3 2−. 2. (C) The conjugate acid of HCO 3 − is H 2 CO (A) The conjugate base of H 2 O is OH −. 4. (C) The conjugate acid of H 2 O is H 3 O +.

© 2013 Pearson Education, Inc. Chapter 10, Section 1 26 Learning Check Identify the acid–base conjugate pairs.

© 2013 Pearson Education, Inc. Chapter 10, Section 1 27 Solution Identify the acid–base conjugate pairs. conjugate acid–base pair

General, Organic, and Biological Chemistry Fourth Edition Karen Timberlake 10.2 Strengths of Acids and Bases Chapter 10 Acids and Bases © 2013 Pearson Education, Inc. Lectures

© 2013 Pearson Education, Inc. Chapter 10 Section 2 29  Strong acids completely ionize (100%) in aqueous solutions. We use a single arrow in the chemical equation. HCl(g) + H 2 O(l) H 3 O + (aq) + Cl − (aq)  Weak acids dissociate only slightly in water to form a solution of mostly molecules and a few ions. H 2 CO 3 (aq) + H 2 O(l) H 3 O + (aq) + HCO 3 − (aq) Strengths of Acids

© 2013 Pearson Education, Inc. Chapter 10 Section 2 30 Strong and Weak Acids There are six strong acids in solution.  HCl, a strong acid, dissociates 100%.  Acetic acid (CH 3 COOH), a weak acid, is mostly molecules and only a few ions.

© 2013 Pearson Education, Inc. Chapter 10 Section 2 31 Weaker acids have a varying degree of strength. The stronger the acid, the weaker the conjugate base. Stronger Acid, Weaker Conjugate Base

© 2013 Pearson Education, Inc. Chapter 10 Section 2 32 Weak acids  make up most of the acids and  have strong conjugate bases. Stronger Acid, Weaker Conjugate Base Increasing Acid Strength Increasing Base Strength

© 2013 Pearson Education, Inc. Chapter 10 Section 2 33 H 2 CO 3 is a diprotic acid. It partially dissociates in water, giving up one H + at a time. H 2 CO 3 (aq) + H 2 O(l) H 3 O + (aq) + HCO 3 − (aq) Because HCO 3 − is also a weak acid, a second dissociation can take place to produce another hydronium ion and the carbonate ion. HCO 3 − (aq) + H 2 O(l) H 3 O + (aq) + CO 3 2− (aq) H 2 CO 3, Weak Acid

© 2013 Pearson Education, Inc. Chapter 10 Section 2 34 H 2 SO 4 is also a diprotic acid. It completely dissociates in water. H 2 SO 4 (aq) + H 2 O(l) H 3 O + (aq) + HSO 4 − (aq) Because HSO 4 − is a weak acid, a second dissociation takes place to produce another hydronium ion and the sulfate ion. HSO 4 − (aq) + H 2 O(l) H 3 O + (aq) + SO 4 2− (aq) H 2 SO 4, Strong Acid

© 2013 Pearson Education, Inc. Chapter 10 Section 2 35 Strong Bases Strong bases  are formed from metals of Groups 1A(1) and 2A(2).  include LiOH, NaOH, KOH, and Ca(OH) 2.  dissociate completely in water. KOH(s) K + (aq) + OH − (aq)

© 2013 Pearson Education, Inc. Chapter 10 Section 2 36 Weak Bases Weak bases  are most other bases.  dissociate only slightly in water.  form only a few ions in water. NH 3 (g) + H 2 O(l) NH 4 + (aq) + OH − (aq)

© 2013 Pearson Education, Inc. Chapter 10 Section 2 37 Common Household Bases Bases in Household Products are used to clean, remove grease, and to open drains.

© 2013 Pearson Education, Inc. Chapter 10 Section 2 38 Learning Check Identify each of the following as a strong or weak acid or base. A. HBr B. HNO 2 C. NaOH D. H 2 SO 4 E. Cu(OH) 2

© 2013 Pearson Education, Inc. Chapter 10 Section 2 39 Solution Identify each of the following as a strong or weak acid or base. A. HBrstrong acid B. HNO 2 weak acid C. NaOHstrong base D. H 2 SO 4 strong acid E. Cu(OH) 2 weak base

© 2013 Pearson Education, Inc. Chapter 10 Section 2 40 Learning Check Identify the stronger acid in each pair. A. HNO 2 or H 2 S B. HCO 3 − or HBr C. H 3 PO 4 or H 3 O +

© 2013 Pearson Education, Inc. Chapter 10 Section 2 41 Solution Identify the stronger acid in each pair. A. HNO 2 or H 2 S B. HCO 3 − or HBr C. H 3 PO 4 or H 3 O +

© 2013 Pearson Education, Inc. Chapter 10 Section 2 42 Acid Dissociation Constant, K a  In a weak acid, the rate of the dissociation of the acid is equal to the rate of the association. HA + H 2 O H 3 O + + A –  The equilibrium expression is indicated below. K a = [H 3 O + ][A – ] [HA]

© 2013 Pearson Education, Inc. Chapter 10 Section 2 43 K a, Formic Acid  Formic acid, HCHO 2, the acid found in bee and ant stings, is a weak acid. HCHO 2 + H 2 O H 3 O + + CHO 2 –  The equilibrium expression is indicated below K a = [H 3 O + ][CHO 2 – ] = 1.8 x [HCHO 2 ]

© 2013 Pearson Education, Inc. Chapter 10 Section 2 44 Acid Characteristics and K a

© 2013 Pearson Education, Inc. Chapter 10 Section 2 45 Some Acid Dissociation Constants K a values for some weak acids are shown in Table 10.4.

© 2013 Pearson Education, Inc. Chapter 10 Section 2 46 Writing K a for a Weak Acid Write the K a for H 2 S. 1. Write the equation for the dissociation of H 2 S. H 2 S(aq) + H 2 O(l) H 3 O + (aq) + HS − (aq) 2. Set up the K a expression. K a =

© 2013 Pearson Education, Inc. Chapter 10 Section 2 47 Learning Check Write the K a for hypochlorous acid, HClO.

© 2013 Pearson Education, Inc. Chapter 10 Section 2 48 Solution Write the K a for hypochlorous acid, HClO. 1. Write the equation for the dissociation of the weak acid, HClO. HClO(aq) + H 2 O(l) H 3 O + (aq) + ClO − (aq) 2. Set up the K a expression. K a =

General, Organic, and Biological Chemistry Fourth Edition Karen Timberlake 10.3 Ionization of Water Chapter 10 Acids and Bases © 2013 Pearson Education, Inc. Lectures

© 2013 Pearson Education, Inc. Chapter 10 Section 3 50 In the ionization of water,  H + is transferred from one H 2 O molecule to another.  one water molecule acts as an acid, while another acts as a base. H 2 O(l) + H 2 O(l) H 3 O + (aq) + OH − (aq) Ionization of Water

© 2013 Pearson Education, Inc. Chapter 10 Section 3 51 The ion product constant, K w, for water at 25  C  is the product of the concentrations of the hydronium and hydroxide ions. K w = [ H 3 O + ][ OH − ]  is obtained from the concentrations in pure water. K w = [ H 3 O + ][ OH − ] K w = [1.0 x 10 −7 M][1.0 x = 1.0 x 10 −14 Ion Product of Water, K w

© 2013 Pearson Education, Inc. Chapter 10 Section 3 52 Pure Water is Neutral In pure water, the ionization of water molecules produces small but equal quantities of H 3 O + and OH − ions.

© 2013 Pearson Education, Inc. Chapter 10 Section 3 53 Acidic Solutions Adding an acid to pure water  increases the [H 3 O + ],  decreases the [OH − ], and  causes the [H 3 O + ] to exceed 1.0 x 10 −7 M.

© 2013 Pearson Education, Inc. Chapter 10 Section 3 54 Basic Solutions Adding a base to pure water,  increases the [OH − ],  decreases the [H 3 O + ], and  causes the [OH − ] to exceed 1.0 x 10 −7 M.

© 2013 Pearson Education, Inc. Chapter 10 Section 3 55 Comparison of [H 3 O + ] and [OH − ]

© 2013 Pearson Education, Inc. Chapter 10 Section 3 56 [H 3 O + ] and [OH − ] in Solutions In neutral, acidic, or basic solutions, the K w at 25  C is always 1.0 x 10 −14.

© 2013 Pearson Education, Inc. Chapter 10 Section 3 57 Guide to Calculating [H 3 O + ] and [OH − ]

© 2013 Pearson Education, Inc. Chapter 10 Section 3 58 Calculating [H 3 O + ] What is the [H 3 O + ] of a solution if [OH − ] is 5.0 x 10 −8 M? Step 1 Write the K w for water. K w = [H 3 O + ][OH − ] Step 2 Solve the K w for the unknown [H 3 O + ]. [H 3 O + ] = 1.0 x 10 −14 [OH − ] Step 3 Substitute the known [OH − ] into the equation and calculate. [H 3 O + ] = 1.0 x 10

© 2013 Pearson Education, Inc. Chapter 10 Section 3 59 If lemon juice has [H 3 O + ] of 2 x 10 −3 M, what is the [OH − ] of the solution? A. 2 x 10 −11 M B. 5 x 10 −11 M C. 5 x 10 −12 M Learning Check

© 2013 Pearson Education, Inc. Chapter 10 Section 3 60 If lemon juice has [H 3 O + ] of 2 x 10 −3 M, what is the [OH − ] of the solution? Step 1 Write the K w for water. K w = [H 3 O + ][OH − ] = 1.0 x 10 −14 Step 2 Solve the K w for the unknown [OH − ]. [OH − ] = 1.0 x 10 −14 [H 3 O + ] Step 3 Substitute the known [H 3 O + ] into the equation and calculate. [2 x 10 −3 ] Answer is C. Solution

© 2013 Pearson Education, Inc. Chapter 10 Section 3 61 General, Organic, and Biological Chemistry Fourth Edition Karen Timberlake 10.4 The pH Scale Chapter 10 Acids and Bases © 2013 Pearson Education, Inc. Lectures

© 2013 Pearson Education, Inc. Chapter 10 Section 3 62 pH Scale The pH of a solution  is used to indicate the acidity of a solution.  has values that range from 0 to 14 representing the H 3 O + concentration of a solution.  is acidic when the values are less than 7.  is neutral with a pH of 7.  is basic when the values are greater than 7.

© 2013 Pearson Education, Inc. Chapter 10 Section 3 63 pH of Everyday Substances

© 2013 Pearson Education, Inc. Chapter 10, Section 4 64 pH: Acidic, Neutral, or Basic Acidic solution pH 1.0 x M Neutral solution pH = 7.0 [H 3 O + ] = 1.0 x M Basic solution pH > 7.0[H 3 O + ] < 1.0 x M

© 2013 Pearson Education, Inc. Chapter 10, Section 4 65 Measuring pH pH can be measured using  a pH meter.  pH papers that turn specific colors when placed in solutions of different pH values.  test papers and a color comparison chart.  indicators that change color with changes in pH.

© 2013 Pearson Education, Inc. Chapter 10 Section 3 66 Identify each solution as acidic, basic, or neutral. ___ A. HCl with a pH = 1.5 ___ B. pancreatic fluid [H 3 O + ] = 1 x 10 −8 M ___ C. Sprite soft drink, pH = 3.0 ___ D. pH = 7.0 ___ E. [OH − ] = 3 x 10 −10 M ___ F. [H 3 O + ] = 5 x 10 −12 M Learning Check

© 2013 Pearson Education, Inc. Chapter 10 Section 3 67 Identify each solution as acidic, basic, or neutral. Acidic A. HCl with a pH = 1.5 Basic B. Pancreatic fluid [H 3 O + ] = 1 x 10 −8 M Acidic C. Sprite soft drink pH = 3.0 Neutral D. pH = 7.0 Acidic E. [OH − ] = 3 x 10 −10 M Basic F. [H 3 O + ] = 5 x 10 −12 Solution

© 2013 Pearson Education, Inc. Chapter 10 Section 3 68 pH is the negative logarithm (base 10) of the [H 3 O + ]. For a solution with [H 3 O + ] = 1 x 10 −4 M: Calculating pH

© 2013 Pearson Education, Inc. Chapter 10, Section 4 69 Guide to Calculating pH

© 2013 Pearson Education, Inc. Chapter 10 Section 3 70 Find the pH of a solution with a [H 3 O + ] of 1.7 x 10 −3 M. Step 1 Enter the [H 3 O + ]. Enter 1.7, then press EE or EXP. Enter 3, and then −/+ to change the sign. 1.7 −03 or 1.7−03 or 1.7E−03 Step 2 Press log key and change the sign. log −/+ Calculate pH from [H 3 O + ] Calculator Display

© 2013 Pearson Education, Inc. Chapter 10 Section 3 71 Find the pH of a solution with a [H 3 O + ] of 1.7 x 10 −3 M. Step 3 Adjust the number of SFs on the right of the decimal point to equal the SFs in the coefficient. 2 SF Calculate pH from [H 3 O + ]

© 2013 Pearson Education, Inc. Chapter 10 Section 3 72 Learning Check What is the pH of coffee if the [H 3 O + ] is 1 x 10 −5 M? A. pH = 9.0 B. pH = 7.0 C. pH = 5.0

© 2013 Pearson Education, Inc. Chapter 10 Section 3 73 Solution What is the pH of coffee if the [H 3 O + ] is 1 x 10 −5 M? Step 1 Enter the [H 3 O + ]. Enter 1, then press EE or EXP. Enter 5, and then −/+ to change the sign. 1 −05 or 1−05 or 1E−05 Step 2 Press the log key and change the sign. Calculator Display

© 2013 Pearson Education, Inc. Chapter 10 Section 3 74 Solution What is the pH of coffee if the [H 3 O + ] is 1 x 10 −5 M? Step 3 Adjust the number of SFs on the right of the decimal point to equal the SFs in the coefficient. Answer is C. 1 SF

© 2013 Pearson Education, Inc. Chapter 10 Section 3 75 The [H 3 O + ] of tomato juice is 2 x 10 −4 M. What is the pH of the solution? A. 4.0 B. 3.7 C Learning Check

© 2013 Pearson Education, Inc. Chapter 10 Section 3 76 Solution The [H 3 O + ] of tomato juice is 2 x 10 −4 M. Step 1 Enter the [H 3 O + ]. Enter 2, then press EE or EXP. Enter 4, and then −/+ to change the sign. 2.0 EE or EXP 4 −/+ = 2 −4 or 2−4 or 1E−4 Step 2 Press the log key and change the sign. Calculator Display

© 2013 Pearson Education, Inc. Chapter 10 Section 3 77 Solution The [H 3 O + ] of tomato juice is 2 x 10 −4 M. Step 3 Adjust the number of SFs on the right of the decimal point to equal the SFs in the coefficient. Answer is B. 1 SF

© 2013 Pearson Education, Inc. Chapter 10 Section 3 78 The [OH − ] of a solution is 1.0 x 10 −3 M. What is the pH? A B C. –11.00 Learning Check

© 2013 Pearson Education, Inc. Chapter 10 Section 3 79 The [OH − ] of a solution is 1.0 x 10 −3 M. What is the pH? Step 1 Enter the [H 3 O + ]. Because [OH − ] is given for the ammonia solution, we need to calculate [H 3 O + ]. We use the ion product constant of water, K w, to obtain [H 3 O + ]. Solution Calculator display

© 2013 Pearson Education, Inc. Chapter 10 Section 3 80 The [OH − ] of a solution is 1.0 x 10 −3 M. What is the pH? Step 2 Press the log key and change the sign. log −/+ Step 3 Adjust the number of SFs to the right of the decimal point to equal the SFs in the coefficient. Answer is B. Solution Calculator display

© 2013 Pearson Education, Inc. Chapter 10, Section 4 81 [H 3 O + ], [OH - ], and pH Values

© 2013 Pearson Education, Inc. Chapter 10, Section 4 82 Guide to Calculating [H 3 O + ] from pH

© 2013 Pearson Education, Inc. Chapter 10 Section 3 83 Calculating [H 3 O + ] from pH Calculate the [H 3 O + ] for a pH value of Step 1 Enter the pH value and change the sign. Enter 8.25 –/+ –8.25 Step 2 Convert –pH to concentration. Press the 2nd function key and then the 10 x key. 2 nd 10 x −09 or −09 or E−09 Or, press the inverse key and then the log key. inv log Calculator display

© 2013 Pearson Education, Inc. Chapter 10 Section 3 84 Calculating [H 3 O + ] from pH Calculate the [H 3 O + ] for a pH value of Step 3 Adjust the SFs in the coefficient. 2 SF

© 2013 Pearson Education, Inc. Chapter 10 Section 3 85 What is the [H 3 O + ] of a solution with a pH of 11.2? A. 6 x 10 − 12 M B x 10 − 12 M C x 10 − 12 M Learning Check

© 2013 Pearson Education, Inc. Chapter 10 Section 3 86 Solution What is the [H 3 O + ] of a solution with a pH of 11.2? Step 1 Enter the pH value and change the sign. Enter 11.2 –/+ –11.2 Step 2 Convert –pH to concentration. Press the 2nd function key and then the 10 x key. 2 nd 10 x −12 or −12 or E−12 Or press the inverse key, and then the log key. inv log Calculator display

© 2013 Pearson Education, Inc. Chapter 10 Section 3 87 Solution What is the [H 3 O + ] of a solution with a pH of 11.2? Step 3 Adjust the SFs in the coefficient. 1 SF

© 2013 Pearson Education, Inc. Chapter 10 Section 3 88 General, Organic, and Biological Chemistry Fourth Edition Karen Timberlake 10.5 Reactions of Acids and Bases Chapter 10 Acids and Bases © 2013 Pearson Education, Inc. Lectures

© 2013 Pearson Education, Inc. Chapter 10 Section 3 89 General, Organic, and Biological Chemistry Fourth Edition Karen Timberlake 10.5 Reactions of Acids and Bases Chapter 10 Acids and Bases © 2013 Pearson Education, Inc. Lectures

© 2013 Pearson Education, Inc. Chapter 10 Section 3 90 Acid Rain Acid rain  is a term given to precipitation, such as rain, snow, hail, or fog, that has a pH of 5.6 or less.  is formed when sulfur impurities from coal and oil react with water and oxygen gas to form H 2 SO 4. degrades marble statues and limestone structures.  interferes with photosynthesis, killing plants and trees.

© 2013 Pearson Education, Inc. Chapter 10 Section 3 91 Acid Rain A marble statue in Washington Square Park has been eroded by acid rain. Acid rain has severely damaged forests in Eastern Europe.

© 2013 Pearson Education, Inc. Chapter 10 Section 3 92 Neutralization is the reaction of an acid, such as HCl and a base, such as NaOH. acid base salt water  The net ionic equation shows that H + combines with OH − to form H 2 O, leaving the ions Na+ and Cl- in solution  Crossing out spectator ions we get Neutralization Reactions

© 2013 Pearson Education, Inc. Chapter 10, Section 4 93 Guide to Balancing an Equation for Neutralization

© 2013 Pearson Education, Inc. Chapter 10 Section 3 94 Write the balanced equation for the neutralization of magnesium hydroxide and nitric acid. Step 1 Write the reactants and products. Step 2 Balance the H in the acid with the OH in the base. Balancing Neutralization Reactions

© 2013 Pearson Education, Inc. Chapter 10 Section 3 95 Write the balanced equation for the neutralization of magnesium hydroxide and nitric acid. Step 3 Balance the H 2 O with the H and OH. Step 4 Write the salt from the remaining ions. Balancing Neutralization Reactions

© 2013 Pearson Education, Inc. Chapter 10 Section 3 96 Learning Check Write the balanced equation for the reaction of the base KOH with the strong acid, H 2 SO 4.

© 2013 Pearson Education, Inc. Chapter 10 Section 3 97 Write the balanced equation for the reaction of the base KOH with the strong acid, H 2 SO 4. Step 1 Write the reactants and products. Step 2 Balance the H in the acid with the OH in the base. Solution

© 2013 Pearson Education, Inc. Chapter 10 Section 3 98 Write the balanced equation for the reaction of the base KOH with the strong acid, H 2 SO 4. Step 3 Balance the H 2 O with the H and OH. Step 4 Write the salt from the remaining ions. Solution

© 2013 Pearson Education, Inc. Chapter 10 Section 3 99 Select the correct group of coefficients for the following neutralization equations. 1. A. 1, 3, 3, 1 B. 3, 1, 1, 1 C. 3, 1, 1, 3 2. A. 3, 2, 2, 2 B. 3, 2, 1, 6 C. 2, 3, 1, 6 Learning Check