Acids and Bases - PowerPoint PPT Presentation

About This Presentation
Title:

Acids and Bases

Description:

CHAPTER 15 ACIDS AND BASES TITRATION Titration: Method used to determine the concentration of an acid or base. EQUIVALENCE POINT Equivalence Point: Point at which the ... – PowerPoint PPT presentation

Number of Views:88
Avg rating:3.0/5.0
Slides: 81
Provided by: kkane
Category:

less

Transcript and Presenter's Notes

Title: Acids and Bases


1
Chapter 15
  • Acids and Bases

2
15.1 What are Acids and Bases?
  • Objectives
  • To name acids and bases.
  • To write formulas for acids and bases.

3
Rules for Naming Acids
  • -ide ? hydro_____ic acid
  • -ate ? _____ic acid
  • -ite ? _____ous acid
  • If a compound begins with hydrogen name it as an
    acid.

4
Examples Naming Acids
  • 1. HCl
  • The anion is chloride (Cl-)
  • For an anion ending in ide ? hydro___ic acid
  • Therefore, the name is hydrochloric acid

5
Examples Naming Acids
  • 1. HCl
  • The anion is chloride (Cl-)
  • For an anion ending in ide ? hydro___ic acid
  • Therefore, the name is hydrochloric acid
  • 2. HNO3
  • The anion is nitrate (NO3-)
  • For an anion ending in ate ? ___ic acid
  • Therefore, the name is nitric acid

6
Examples Naming Acids
  • 1. HCl
  • The anion is chloride (Cl-)
  • For an anion ending in ide ? hydro___ic acid
  • Therefore, the name is hydrochloric acid
  • 2. H2SO4
  • The anion is sulfate (SO42-)
  • For an anion ending in ate ? ___ic acid
  • Therefore, the name is sulfuric acid
  • 3. H2SO3
  • The anion sulfite (SO32-)
  • For an anion ending in ite ? ___ous acid
  • Therefore, the name acid sulfurous acid

7
Name the following compound HBr
  1. Bromic acid
  2. Bromous acid
  3. Hydrobromic acid
  4. Hydrobromous acid
  5. None of the above

8
Name the following compound HBr
  1. Bromic acid
  2. Bromous acid
  3. Hydrobromic acid
  4. Hydrobromous acid
  5. None of the above

9
Name the following compound H2C2O4
  1. Chromic acid
  2. Oxalate acid
  3. Dihydrogen dicarbon tetraoxide
  4. Oxalic acid
  5. None of the above

10
Name the following compound H2C2O4
  1. Chromic acid
  2. Oxalate acid
  3. Dihydrogen dicarbon tetraoxide
  4. Oxalic acid
  5. None of the above

11
Practice Naming Acids
  • 1. H2SO3
  • 2. HF
  • 3. H3PO4
  • 4. HNO3
  • 5. HI

12
Practice Naming Acids
  • 1. H2SO3 sulfurous acid
  • 2. HF hyrofluoric acid
  • 3. H3PO4 phosphoric acid
  • 4. HNO3 nitric acid
  • 5. HI hydroiodic acid

13
Examples Writing Formulas for Acids
H SO42-
  • 1. Sulfuric acid
  • The anion is sulfate (SO42-)
  • The cation is H
  • Criss-cross charges to get H2SO4
  • 2. Carbonic acid
  • The anion is carbonate (CO32-)
  • The cation is H
  • Criss-cross charges to get H2CO3

H2SO4
H CO32-
H2CO3
14
Practice Writing Formulas for Acids
  • 1. Hydrochloric acid
  • 2. Nitric acid
  • 3. Phosphorous acid
  • 4. Hydroiodic acid

15
Practice Writing Formulas for Acids
  • 1. Hydrochloric acid HCl
  • 2. Nitric acid HNO3
  • 3. Phosphorous acid H3PO3
  • 4. Hydroiodic acid HI

16
Acids you should know
Strong Acids Weak Acids
Hydrochloric Acid Phosphoric Acid
Sulfuric Acid Acetic Acid
Nitric Acid
17
Some Bases
Strong Bases Weak Bases
Sodium Hydroxide Ammonia
Potassium Hydroxide Sodium Carbonate
Calcium Hydroxide Potassium Carbonate
Barium Hydroxide
Sodium Phosphate
18
15.1 What are acids and bases? continued
  • Objectives
  • To list properties of acids and bases.
  • To define acid and base.
  • To identify the acid, base, conjugate acid, and
    conjugate base in a chemical reaction.

19
Properties of Acids
  • Taste sour
  • Form Hydronium Ions (H3O)
  • Conduct electricity
  • React with metals

20
Properties of Bases
  • Taste bitter
  • Feel slippery
  • Generate Hydroxide Ions (OH-)

21
Acid
  • Arrhenius Acid any substance that, when added to
    water, increases the hydronium ion (H3O)
    concentration
  • Note H and H3O are used
    interchangeably

22
Base
  • Arrhenius Base generates hydroxide ions (OH-)
    when dissolved in water

23
BrØnsted-LowRY Acid
  • A substance that donates a proton (H) to another
    substance.

24
BrØwnsted-lowry base
  • A substance that accepts a proton (H).

25
Conjugate Acid and Conjugate Base
  • Conjugate Acid an acid that forms when the base
    gains a H
  • Conjugate Base the base that forms when an acid
    loses an H

26
Identify the conjugate base for the following
acids
Acid Conjugate Base
HCl Cl-
H2SO4
H3O
HSO4-
HOCl
H2PO4-
NH4
27
Identify the conjugate base for the following
acids
Acid Conjugate Base
HCl Cl-
H2SO4 HSO4-
H3O H2O
HSO4- SO42-
HOCl OCl-
H2PO4- HPO42-
NH4 NH3
28
Identify the conjugate acid for the following
bases
Conjugate Acid Base
NH4 NH3
HCO3-
HS-
Br-
29
Identify the conjugate acid for the following
bases
Conjugate Acid Base
NH4 NH3
H2CO3 HCO3-
H2S HS-
HBr Br-
30
Identify the acid, base, conjugate acid, and
conjugate base in the following chemical
reactions
  • HCl OH- ? Cl- H2O
  • acid base c. base c. acid
  • 2. HNO3 OH- ? NO3- H2O
  • 3. H2O HCO3- ? H2CO3 OH-

31
Identify the acid, base, conjugate acid, and
conjugate base in the following chemical
reactions
  • HCl OH- ? Cl- H2O
  • acid base c. base c. acid
  • 2. HNO3 OH- ? NO3- H2O
  • acid base c. base c. acid
  • 3. H2O HCO3- ? H2CO3 OH-
  • acid base c. acid c. base

32
Amphoteric Substances
  • An amphoteric substance can donate AND accept
    protons.
  • Example HCO3- is amphoteric
  • HCO3- NH3 ? CO32- NH4
  • Acid Base C. Base C. Acid
  • HCO3- H3O ? H2CO3 H2O
  • Base Acid C. Acid C. Base

33
15.2 Acidity, Basicity, and pH
  • Objective
  • To calculate the concentration of the hydronium
    ion and the hydroxide ion.

34
Self-Ionization of Water
  • H2O(l) H2O(l) ? H3O(aq) OH-(aq)
  • H3O OH- 1.00 x 10-7 M
  • What is the Keq for water?

35
Self-Ionization of Water
  • H2O(l) H2O(l) ? H3O(aq) OH-(aq)
  • H3O OH- 1.00 x 10-7 M
  • What is the Keq for water?
  • Keq H3OOH- (1.00 x 10-7)(1.00 x 10-7)
  • Keq 1.00 x 10-14 Kw

36
Summary
  • Kw H3OOH-
  • Kw 1.00 x 10-14

37
Determining H3O and OH- using Kw
  • Step 1 Write the Kw expression.
  • Step 2 Determine concentrations.
  • Step 3 Solve!

38
Example
  • What is OH- in a 3.00 x 10-5 M solution of HCl?
  • Kw H3OOH-
  • 1 x 10-14 (3.00 x 10-5) OH-
  • OH- 3.33 x 10-10 M

39
Practice
  1. Calculate the hydronium ion concentration in an
    aqueous solution of KOH that has a hydroxide ion
    concentration of 7.24 x 10-4 M.

40
Practice
  1. Calculate the hydronium ion concentration in an
    aqueous solution of KOH that has a hydroxide ion
    concentration of 7.24 x 10-4 M.
  2. What is the OH- in a 0.450 M solution of HNO3?

41
Practice
  • 3. What is H3O in a solution of NaOH whose
    concentration is 3.75 x 10-2 M?

42
Practice
  • 3. What is H3O in a solution of NaOH whose
    concentration is 3.75 x 10-2 M?
  • 4. Calculate the hydroxide ion concentration of a
    0.200 M solution of HClO4.

43
15.2 Acidity, Basicity, and pH continued
  • Objective
  • To calculate pH.

44
pH
  • pH A value used to represent acidity or
    alkalinity (basicity) of a solution.

45
Measuring pH
  • Indicators dyes that turn different colors in
    solutions of different pH
  • Examples litmus paper, bromothymol blue, methyl
    orange, phenolphthalein

46
(No Transcript)
47
Calculating pH
  • pH -logH3O

48
Example
  • What is the pH of a solution with a 0.05 M
    hydronium ion concentration?
  • pH -logH3O
  • pH -log(0.05)
  • pH 1.30
  • Note pH does not have units.

49
Practice
  1. What is the pH of 0.00010 M solution of nitric
    acid?

50
Practice
  1. What is the pH of 0.00010 M solution of nitric
    acid?
  2. Calculate the pH if H3O 5.0 x 10-3 M.

51
Practice
  1. What is the pH of 0.00010 M solution of nitric
    acid?
  2. Calculate the pH if H3O 5.0 x 10-3 M.
  3. What is the pH of a 0.2 M solution of a strong
    acid?

52
15.2 Acidity, Basicity, and pH
  • Objective
  • To calculate pOH.

53
Calculating pOH
  • pOH -logOH-
  • pH pOH 14

54
Example
  • What is the pH and pOH of 0.00010 M solution of
    HNO3?
  • pH -logH3O
  • pH -log(0.00010)
  • pH 4.0
  • pH pOH 14
  • 4.0 pOH 14
  • pOH 10

55
Practice
  1. What is the pH and pOH of a 0.0136 M solution of
    KOH?

56
Practice
  1. What is the pH and pOH of a 0.0136 M solution of
    KOH?
  2. What is the pH and pOH of a 1.2 x 10-3 HBr
    solution?

57
Practice
  1. What is the pH and pOH of a 0.0136 M solution of
    KOH?
  2. What is the pH and pOH of a 1.2 x 10-3 HBr
    solution?
  3. What is the pH and pOH of a 2.34 x 10-5 NaOH
    solution?

58
15.2 Acidity, Basicity, and pH
  • Objective
  • To calculate H3O and OH- from pH.

59
Calculating H3O and OH- from pH
  • pH -logH3O
  • H3O 10-pH

pOH -logOH- OH- 10-pOH
60
Example
  • What are the concentrations of the hydronium and
    hydroxide ions in a sample of rain that has a pH
    of 5.05?
  • H3O 10-pH
  • H3O 10-5.05
  • H3O 8.91 x 10-6 M
  • Kw H3OOH-
  • 1 x 10-14 (8.91 x 10-6)OH-
  • OH- 1.12 x 10-9 M

61
Practice
  1. What is the hydronium ion concentration in a
    fruit juice that has a pH of 3.3?

62
Practice
  1. What is the hydronium ion concentration in a
    fruit juice that has a pH of 3.3?
  2. A commercial window-cleaning liquid has a pH of
    11.7. What is the hydroxide ion concentration?

63
Practice
  1. What is the hydronium ion concentration in a
    fruit juice that has a pH of 3.3?
  2. A commercial window-cleaning liquid has a pH of
    11.7. What is the hydroxide ion concentration?
  3. If the pH of a solution is 8.1, what is the
    hydronium ion concentration?

64
14.3 Neutralizations and Titrations
  • Objective To determine the concentration of an
    acid or base used to reach the equivalence point
    in a titration.

65
Neutralization Reaction(acid-base reaction)
  • General Equation
  • Acid Base ? Salt Water
  • Example
  • HCl NaOH ? NaCl H2O

66
Titration
  • Titration Method used to determine the
    concentration of an acid or base.

67
Equivalence Point
  • Equivalence Point Point at which the
    neutralization reaction is complete

68
End Point
  • End Point The instant at which the indicator
    changes color

69
Titration Calculations
  • MAVA MBVB
  • where A is acid and B is base

70
Example
  • A student titrates 40.0 mL of an HCl solution of
    unknown concentration with a 0.5500 M NaOH
    solution. The volume of base solution needed to
    reach the equivalence point is 24.64 mL. What is
    the concentration of HCl solution?
  • Acid (HCl) Base (NaOH)
  • VA 40.0 mL VB 24.64 mL
  • MA ? MB 0.5500 M
  • MAVA MBVB
  • MA (40.0 mL) (0.5500 M) (24.64 mL)
  • MA 0.3388 M

71
Practice
  1. If it takes 25 mL of 0.05 M HCl to neutralize 345
    mL of NaOH solution, what is the concentration of
    the NaOH solution?

72
Practice
  1. If it takes 25 mL of 0.05 M HCl to neutralize 345
    mL of NaOH solution, what is the concentration of
    the NaOH solution?
  2. If it takes 50 mL of 0.5 M KOH solution to
    completely neutralize 125 mL of hydrochloric acid
    solution, what is the concentration of
    hyrochloric acid solution?

73
Practice
  • 3. How much 1.5 M Ca(OH)2 is necessary to exactly
    neutralize 20.0 mL of 2.5 M sulfuric acid?

74
Practice
  • 3. How much 1.5 M Ca(OH)2 is necessary to exactly
    neutralize 20.0 mL of 2.5 M sulfuric acid?
  • 4. A 25.0 mL sample was titrated to the endpoint
    with 15.0 mL of 2.0 M NaOH. What is the molarity
    of HCl?

75
Practice
  • 3. How much 1.5 M Ca(OH)2 is necessary to exactly
    neutralize 20.0 mL of 2.5 M sulfuric acid?
  • 4. A 25.0 mL sample was titrated to the endpoint
    with 15.0 mL of 2.0 M NaOH. What is the molarity
    of Hcl?
  • 5. How much 0.75 M HCl is needed to completely
    neutralize 25.0 mL of KOH?

76
15.3 Neutralizations and Titrations
  • Objective To determine the concentration of
    polyprotic acids needed to reach the equivalence
    point in a titration.

77
Titrations with Polyprotic Acids
  • MAVA MBVB
  • With a twist
  • MAVA (H) MBVB(OH-)

78
Example
  • What volume of a 1.366 M solution of NaOH would
    be required to titrate 47.22 mL of a 2.075 M
    solution of sulfuric acid?
  • Acid (H2SO4) Base (NaOH)
  • MA 2.075 M MB 1.366 M
  • VA 47.22 mL VB ?
  • H 2 OH- 1
  • MAVA (H) MBVB(OH-)
  • (2.075 M) (47.22 mL) (2) (1.366 M) (VB)(1)
  • VB 143.5 mL

79
Practice
  1. How much 1.5 M NaOH is necessary to exactly
    neutralize 20.0 mL of 2.5 M phosphoric acid?

80
Practice
  1. How much 1.5 M NaOH is necessary to exactly
    neutralize 20.0 mL of 2.5 M phosphoric acid?
  2. How much 0.5 M nitric acid is necessary to
    titrate 25.0 mL of 0.05 calcium hydroxide
    solution to the endpoint?
Write a Comment
User Comments (0)
About PowerShow.com