Presentation is loading. Please wait.

Presentation is loading. Please wait.

Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Hewitt/Lyons/Suchocki/Yeh Conceptual Integrated Science Chapter 13 CHEMICAL.

Similar presentations


Presentation on theme: "Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Hewitt/Lyons/Suchocki/Yeh Conceptual Integrated Science Chapter 13 CHEMICAL."— Presentation transcript:

1 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Hewitt/Lyons/Suchocki/Yeh Conceptual Integrated Science Chapter 13 CHEMICAL REACTIONS

2 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley This lecture will help you understand: Chemical Reactions and Equations Acid–Base Reactions Salts Solutions: Acidic, Basic, or Neutral The pH Scale Oxidation-Reduction Reactions Corrosion and Combustion Reaction Rates Exo- and Endothermic Reactions Entropy and Chemical Reactions

3 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Chemical Reactions and Equations During a chemical reaction, one or more new compounds are formed as a result of the rearrangement of atoms. Reactants Products

4 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Chemical Reactions and Equations Law of Mass Conservation: No atoms are gained or lost during any reaction.

5 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Chemical Reactions and Equations Law of Mass Conservation: No atoms are gained or lost during any reaction. The number of times atoms appear before the arrow must be equal to the number of times they appear after the arrow.

6 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley In total, how many atoms are represented by the following schematic for a chemical reaction? A.2 B.5 C.6 D.12 Chemical Reactions and Equations CHECK YOUR NEIGHBOR

7 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley In total, how many atoms are represented by the following schematic for a chemical reaction? A.2 B.5 C.6 D.12 Chemical Reactions and Equations CHECK YOUR ANSWER Explanation: The atoms of the reactants are the SAME atoms of the products, except in a different configuration.

8 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley In total, how many atoms are represented by the following schematic for a chemical reaction? A.2 B.5 C.6 D.12 Chemical Reactions and Equations CHECK YOUR ANSWER Explanation: The atoms of the reactants are the SAME atoms of the products, except in a different configuration. reactants

9 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley In total, how many atoms are represented by the following schematic for a chemical reaction? A.2 B.5 C.6 D.12 Chemical Reactions and Equations CHECK YOUR ANSWER Explanation: The atoms of the reactants are the SAME atoms of the products, except in a different configuration. reactants

10 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley In total, how many atoms are represented by the following schematic for a chemical reaction? A.2 B.5 C.6 D.12 Chemical Reactions and Equations CHECK YOUR ANSWER Explanation: The atoms of the reactants are the SAME atoms of the products, except in a different configuration. reactants

11 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley In total, how many atoms are represented by the following schematic for a chemical reaction? A.2 B.5 C.6 D.12 Chemical Reactions and Equations CHECK YOUR ANSWER Explanation: The atoms of the reactants are the SAME atoms of the products, except in a different configuration. reactants

12 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley In total, how many atoms are represented by the following schematic for a chemical reaction? A.2 B.5 C.6 D.12 Chemical Reactions and Equations CHECK YOUR ANSWER Explanation: The atoms of the reactants are the SAME atoms of the products, except in a different configuration. products

13 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley In total, how many atoms are represented by the following schematic for a chemical reaction? A.2 B.5 C.6 D.12 Chemical Reactions and Equations CHECK YOUR ANSWER products “conventional” equation format All you see here are six different atoms!

14 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Chemical Reactions and Equations CHECK YOUR NEIGHBOR Is this reaction balanced? A.Yes B.No

15 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Chemical Reactions and Equations CHECK YOUR ANSWER Is this reaction balanced? A.Yes B.No

16 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Chemical Reactions and Equations CHECK YOUR NEIGHBOR How many “diatomic” molecules are represented? A.1 B.2 C.3 D.4

17 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley How many “diatomic” molecules are represented? A.1 B.2 C.3 D.4 Chemical Reactions and Equations CHECK YOUR ANSWER Explanation: The diatomic molecule shown with the products is actually the same molecule shown to the left with the reactants. What happened here is that this molecule didn’t react. beforeafter

18 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley How many “diatomic” molecules are represented? A.1 B.2 C.3 D.4 Chemical Reactions and Equations CHECK YOUR ANSWER Explanation: The diatomic molecule shown with the products is actually the same molecule shown to the left with the reactants. What happened here is that this molecule didn’t react. beforeafter

19 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Is the following chemical equation balanced? A.No, because the molecules have changed. B.Yes, because the coefficients on each side add up to the same number. C.No, because there are more oxygen atoms in the products. D.Yes, because the same atoms appear before and after. Chemical Reactions and Equations CHECK YOUR NEIGHBOR 1 CH 4 + 2 O 2  2 H 2 O + 1 CO 2

20 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Is the following chemical equation balanced? A.No, because the molecules have changed. B.Yes, because the coefficients on each side add up to the same number. C.No, because there are more oxygen atoms in the products. D.Yes, because the same atoms appear before and after. Chemical Reactions and Equations CHECK YOUR ANSWER 1 CH 4 + 2 O 2  2 H 2 O + 1 CO 2

21 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Acid–Base Reactions

22 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Acid–Base Reactions

23 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Acid–Base Reactions Acid A chemical that donates a hydrogen ion, H + Base A chemical that accepts a hydrogen ion, H +

24 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The hydrogen atom H

25 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The hydrogen atom H

26 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The hydrogen atom H

27 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The hydrogen atom H

28 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The hydrogen atom H

29 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The hydrogen atom H

30 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The hydrogen atom H

31 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley H+H+ The hydrogen ion

32 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley H+H+ The hydrogen ion

33 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley H+H+ The hydrogen ion

34 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley H+H+ The hydrogen ion

35 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley H+H+ The hydrogen ion

36 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley H+H+ The hydrogen ion

37 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley H+H+ The hydrogen ion

38 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley H+H+ The hydrogen ion

39 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley H+H+ The hydrogen ion proton

40 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley BaseBase AcceptsAccepts AcidAcid DonatesDonates

41 H2OH2OHCl +

42 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley H2OH2OHCl +

43 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley H3O+H3O+ Cl – +

44 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley H3O+H3O+ Cl – H2OH2OHCl ++

45 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley H3O+H3O+ Cl – H2OH2OHCl ++

46 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley H3O+H3O+ Cl – H2OH2OHCl ++ donordonor acceptoracceptor

47 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley H3O+H3O+ Cl – H2OH2OHCl ++ (acid)(base)

48 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley H2OH2ONH 3 +

49 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley H2OH2ONH 3 +

50 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley NH 4 + OH – +

51 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley H2OH2ONH 3 +

52 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley NH 4 + OH – +

53 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley NH 4 + OH – H2OH2ONH 3 ++

54 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley NH 4 + OH – H2OH2ONH 3 ++

55 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley NH 4 + OH – H2OH2ONH 3 ++ donordonor acceptoracceptor

56 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley NH 4 + OH – H2OH2ONH 3 ++ (acid)(base)

57 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley NH 4 + OH – H2OH2ONH 3 ++

58 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley NH 4 + OH – H2OH2ONH 3 ++

59 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley NH 4 + OH – H2OH2ONH 3 + (acid)(base) +

60 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley NH 4 + OH – H2OH2ONH 3 ++ (acid)(base)(acid)(base)

61 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley When water behaves as an acid, what does it lose? A.A hydrogen ion. B.A hydrogen atom. C.An electron. D.Water can’t behave as an acid. Acid–Base Reactions CHECK YOUR NEIGHBOR

62 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley When water behaves as an acid, what does it lose? A.A hydrogen ion. B.A hydrogen atom. C.An electron. D.Water can’t behave as an acid. Acid – Base Reactions CHECK YOUR ANSWER

63 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley When water behaves as a base, what does it gain? A.A hydrogen ion. B.A hydrogen atom. C.An electron. D.Water can’t behave as an acid. Acid – Base Reactions CHECK YOUR NEIGHBOR

64 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley When water behaves as a base, what does it gain? A.A hydrogen ion. B.A hydrogen atom. C.An electron. D.Water can’t behave as an acid. Acid – Base Reactions CHECK YOUR ANSWER

65 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Which water molecule is behaving as an acid, and which is behaving as a base? A.Molecule B as a base; Molecule A as an acid B.Molecule B as an acid; Molecule A as a base C.Both Molecules A and B are behaving as acids. D.Both Molecules A and B are behaving as bases. Acid – Base Reactions CHECK YOUR NEIGHBOR Molecule AMolecule B H O H H + H O H H O H O H –

66 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Which water molecule is behaving as an acid, and which is behaving as a base? A.Molecule B as a base; Molecule A as an acid B.Molecule B as an acid; Molecule A as a base C.Both Molecules A and B are behaving as acids. D.Both Molecules A and B are behaving as bases. Acid – Base Reactions CHECK YOUR ANSWER Molecule AMolecule B H O H H + H O H H O H O H –

67 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Which water molecule is behaving as an acid, and which is behaving as a base? A.Molecule B as a base; Molecule A as an acid B.Molecule B as an acid; Molecule A as a base C.Both Molecules A and B are behaving as acids. D.Both Molecules A and B are behaving as bases. Acid – Base Reactions CHECK YOUR ANSWER Molecule AMolecule B H O H H O H

68 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Which water molecule is behaving as an acid, and which is behaving as a base? A.Molecule B as a base; Molecule A as an acid B.Molecule B as an acid; Molecule A as a base C.Both Molecules A and B are behaving as acids. D.Both Molecules A and B are behaving as bases. Acid – Base Reactions CHECK YOUR ANSWER Molecule AMolecule B H O H H O H

69 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Which water molecule is behaving as an acid, and which is behaving as a base? A.Molecule B as a base; Molecule A as an acid B.Molecule B as an acid; Molecule A as a base C.Both Molecules A and B are behaving as acids. D.Both Molecules A and B are behaving as bases. Acid – Base Reactions CHECK YOUR ANSWER Molecule A H O H H+H+ O H –

70 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Which water molecule is behaving as an acid, and which is behaving as a base? A.Molecule B as a base; Molecule A as an acid B.Molecule B as an acid; Molecule A as a base C.Both Molecules A and B are behaving as acids. D.Both Molecules A and B are behaving as bases. Acid – Base Reactions CHECK YOUR ANSWER Molecule A H O H H+H+ O H –

71 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Which water molecule is behaving as an acid, and which is behaving as a base? A.Molecule B as a base; Molecule A as an acid B.Molecule B as an acid; Molecule A as a base C.Both Molecules A and B are behaving as acids. D.Both Molecules A and B are behaving as bases. Acid – Base Reactions CHECK YOUR ANSWER Molecule A H O H H+H+ O H –

72 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Which water molecule is behaving as an acid, and which is behaving as a base? A.Molecule B as a base; Molecule A as an acid B.Molecule B as an acid; Molecule A as a base C.Both Molecules A and B are behaving as acids. D.Both Molecules A and B are behaving as bases. Acid – Base Reactions CHECK YOUR ANSWER + H O H H O H –

73 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Salts Salt: An ionic compound formed from the reaction of an acid and a base.

74 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Salts Salt: An ionic compound formed from the reaction of an acid and a base.

75 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Salts Salt: An ionic compound formed from the reaction of an acid and a base.

76 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley What salt forms from the reaction of hydrogen chloride, HCl, with potassium hydroxide, KOH? A.KCl B.H 3 OCl C.KOH 2 D.KOH 2 Cl Salts CHECK YOUR NEIGHBOR

77 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley What salt forms from the reaction of hydrogen chloride, HCl, with potassium hydroxide, KOH? A.KCl B.H 3 OCl C.KOH 2 D.KOH 2 Cl Salts CHECK YOUR ANSWER Explanation: The K + from the KOH combines with the Cl – from the HCl.

78 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Solutions: Acidic, Basic, or Neutral Water can behave as an acid or a base.

79 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Solutions: Acidic, Basic, or Neutral Water can behave as an acid or a base. In pure water, for every one hydronium ion, H 3 O +, formed, there is a hydroxide ion, OH –, formed.

80 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Solutions: Acidic, Basic, or Neutral Water can behave as an acid or a base. In pure water, for every one hydronium ion, H 3 O +, formed, there is a hydroxide ion, OH –, formed. So in pure water, [H 3 O + ] = [OH – ] = 0.0000001 M = 10 –7 M.

81 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Solutions: Acidic, Basic, or Neutral Water can behave as an acid or a base. In pure water, for every one hydronium ion, H 3 O +, formed, there is a hydroxide ion, OH –, formed. So, in pure water, [H 3 O + ] = [OH – ] = 0.0000001 M = 10 –7 M.

82 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Solutions: Acidic, Basic, or Neutral Water can behave as an acid or a base. Add hydronium ions, H 3 O +, and the solution is “acidic,” Add hydroxide ions, OH –, and the solution is “basic.”

83 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Solutions: Acidic, Basic, or Neutral

84 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley As sodium hydroxide, NaOH, is added to water, the hydroxide ion, OH –, concentration A.increases. B.decreases. C.remains the same. Solutions: Acidic, Basic, or Neutral CHECK YOUR NEIGHBOR

85 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley As sodium hydroxide, NaOH, is added to water, the hydroxide ion, OH –, concentration A.increases. B.decreases. C.remains the same. Solutions: Acidic, Basic, or Neutral CHECK YOUR ANSWER Explanation: The bond between sodium and oxygen is ionic. When dissolved in water, it separates into sodium ions and hydroxide ions, much like sodium chloride, NaCl, separates into sodium and chloride ions.

86 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The pH Scale pH is a measure of the concentration of hydronium ions, H 3 O +.

87 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The pH Scale pH is a measure of the concentration of hydronium ions, H 3 O +. pH = –log [H 3 O + ]

88 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The pH Scale pH is a measure of the concentration of hydronium ions, H 3 O +. pH = –log [H 3 O + ] For pure water: pH = –log (10 –7 ) pH = –(– 7) pH = 7

89 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The pH Scale pH is a measure of the concentration of hydronium ions, H 3 O +. pH = –log [H 3 O + ] For pure water: pH = –log (10 –7 ) pH = –(–7) pH = 7 What is a log?

90 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The pH Scale The “log” of a number is simply the power to which ten is raised. The log of 10 3, for example, is 3.

91 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The pH Scale The “log” of a number is simply the power to which ten is raised. The log of 10 3, for example, is 3. Quiz Time What is the log of 10 2 ?

92 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The pH Scale The “log” of a number is simply the power to which ten is raised. The log of 10 3, for example, is 3. Quiz Time What is the log of 10 2 ? Log 10 2 = 2 (the power to which 10 is raised)

93 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The pH Scale The “log” of a number is simply the power to which ten is raised. The log of 10 3, for example, is 3. 10 3 = 1000

94 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The pH Scale The “log” of a number is simply the power to which ten is raised. The log of 10 3, for example, is 3. 10 3 = 1000 10 2 = 100

95 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The pH Scale The “log” of a number is simply the power to which ten is raised. The log of 10 3, for example, is 3. 10 3 = 1000 10 2 = 100 10 1 = 10

96 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The pH Scale The “log” of a number is simply the power to which ten is raised. The log of 10 3, for example, is 3. 10 3 = 1000 10 2 = 100 10 1 = 10 10 –1 = 0.1

97 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The pH Scale The “log” of a number is simply the power to which ten is raised. The log of 10 3, for example, is 3. 10 3 = 1000 10 2 = 100 10 1 = 10 10 –1 = 0.1 10 –2 = 0.01

98 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The pH Scale The “log” of a number is simply the power to which ten is raised. The log of 10 3, for example, is 3. 10 3 = 1000 10 2 = 100 10 1 = 10 10 –1 = 0.1 10 –2 = 0.01 10 –3 = 0.001

99 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The pH Scale The “log” of a number is simply the power to which ten is raised. The log of 10 3, for example, is 3. 10 3 = 1000 10 2 = 100 10 1 = 10 10 0 = ? 10 –1 = 0.1 10 –2 = 0.01 10 –3 = 0.001 Three zeros

100 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The pH Scale The “log” of a number is simply the power to which ten is raised. The log of 10 3, for example, is 3. 10 3 = 1000 10 2 = 100 10 1 = 10 10 0 = ? 10 –1 = 0.1 10 –2 = 0.01 10 –3 = 0.001 Two zeros

101 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The pH Scale The “log” of a number is simply the power to which ten is raised. The log of 10 3, for example, is 3. 10 3 = 1000 10 2 = 100 10 1 = 10 10 0 = ? 10 –1 = 0.1 10 –2 = 0.01 10 –3 = 0.001 One zero

102 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The pH Scale The “log” of a number is simply the power to which ten is raised. The log of 10 3, for example, is 3. 10 3 = 1000 10 2 = 100 10 1 = 10 10 0 = 1 10 –1 = 0.1 10 –2 = 0.01 10 –3 = 0.001 Zero zeros!

103 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The pH Scale The “log” of a number is simply the power to which ten is raised. The log of 10 3, for example, is 3. 10 3 = 1000 10 2 = 100 10 1 = 10 10 0 = 1 10 –1 = 0.1 10 –2 = 0.01 10 –3 = 0.001 Quiz Time Log 1000 = ?

104 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The pH Scale The “log” of a number is simply the power to which ten is raised. The log of 10 3, for example, is 3. 10 3 = 1000 10 2 = 100 10 1 = 10 10 0 = 1 10 –1 = 0.1 10 –2 = 0.01 10 –3 = 0.001 Quiz Time Log 1000 = ? Log 10 3 =

105 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The pH Scale The “log” of a number is simply the power to which ten is raised. The log of 10 3, for example, is 3. 10 3 = 1000 10 2 = 100 10 1 = 10 10 0 = 1 10 –1 = 0.1 10 –2 = 0.01 10 –3 = 0.001 Quiz Time Log 1000 = ? Log 10 3 = 3

106 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The pH Scale The “log” of a number is simply the power to which ten is raised. The log of 10 3, for example, is 3. 10 3 = 1000 10 2 = 100 10 1 = 10 10 0 = 1 10 –1 = 0.1 10 –2 = 0.01 10 –3 = 0.001 Quiz Time Log 1 = ?

107 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The pH Scale The “log” of a number is simply the power to which ten is raised. The log of 10 3, for example, is 3. 10 3 = 1000 10 2 = 100 10 1 = 10 10 0 = 1 10 –1 = 0.1 10 –2 = 0.01 10 –3 = 0.001 Quiz Time Log 1 = ? Log 10 0 =

108 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The pH Scale The “log” of a number is simply the power to which ten is raised. The log of 10 3, for example, is 3. 10 3 = 1000 10 2 = 100 10 1 = 10 10 0 = 1 10 –1 = 0.1 10 –2 = 0.01 10 –3 = 0.001 Quiz Time Log 1 = ? Log 10 0 = 0

109 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The pH Scale The “log” of a number is simply the power to which ten is raised. The log of 10 3, for example, is 3. 10 3 = 1000 10 2 = 100 10 1 = 10 10 0 = 1 10 –1 = 0.1 10 –2 = 0.01 10 –3 = 0.001 Quiz Time Log 10 – 7 =

110 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The pH Scale The “log” of a number is simply the power to which ten is raised. The log of 10 3, for example, is 3. 10 3 = 1000 10 2 = 100 10 1 = 10 10 0 = 1 10 –1 = 0.1 10 –2 = 0.01 10 –3 = 0.001 Quiz Time Log 10 – 7 = – 7

111 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The pH Scale pH = –log [H 3 O + ] For acidic water pH < 7, for example: pH = –log (10 –5 ) pH = –(–5) pH = 5

112 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The pH Scale pH = –log [H 3 O + ] For basic water pH > 7, for example: pH = –log (10 –9 ) pH = –(–9) pH = 9

113 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley The pH Scale

114 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Integrated Science—Earth Science

115 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Oxidation-Reduction Reactions Acid–Base reactions: transfer of proton

116 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Oxidation-Reduction Reactions Acid–Base reactions: transfer of proton Oxidation-Reduction reactions: transfer of ???

117 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Oxidation-Reduction Reactions Acid–Base reactions: transfer of proton Oxidation-Reduction reactions: transfer of electron

118 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Oxidation-Reduction Reactions Oxidation: The loss of an electron

119 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Oxidation-Reduction Reactions Oxidation: The loss of an electron 2 Na 2 Na + + 2 e –

120 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Oxidation-Reduction Reactions Oxidation: The loss of an electron 2 Na 2 Na + + 2 e – Reduction: The gain of an electron

121 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Oxidation-Reduction Reactions Oxidation: The loss of an electron 2 Na 2 Na + + 2 e – Reduction: The gain of an electron Cl 2 + 2 e – 2 Cl –

122 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Oxidation-Reduction Reactions Oxidation: The loss of an electron 2 Na 2 Na + + 2 e – Reduction: The gain of an electron Cl 2 + 2 e – 2 Cl – “Leo” “Ger”

123 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Oxidation-Reduction Reactions Oxidation: The loss of an electron 2 Na 2 Na + + 2 e – Reduction: The gain of an electron Cl 2 + 2 e – 2 Cl – “Leo” “Ger” (Leo the lion went “Ger”)

124 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Oxidation-Reduction Reactions 2 Na + Cl 2 2 Na + + 2 Cl –

125 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Oxidation-Reduction Reactions

126 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Oxidation-Reduction Reactions

127 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley What element within the reactants is oxidized in the following equation, and what element is reduced? I 2 + 2 Br –  2 I – + Br 2 A.Iodine, I, is oxidized, while the bromine ion, Br –, is reduced. B.Iodine, I, is reduced, while the bromine ion, Br –, is oxidized. C.Both the iodine, I, and the bromine ion, Br –, are reduced. D.Both the iodine, I, and the bromine ion, Br –, are oxidized. Oxidation Reduction Reactions CHECK YOUR NEIGHBOR

128 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley I 2 + 2 Br –  2 I – + Br 2 A.Iodine, I, is oxidized, while the bromine ion, Br –, is reduced. B.Iodine, I, is reduced, while the bromine ion, Br –, is oxidized. C.Both the iodine, I, and the bromine ion, Br –, are reduced. D.Both the iodine, I, and the bromine ion, Br –, are oxidized. Explanation: Note how the iodine gains a negative charge, while the bromine loses the negative charge. What element within the reactants is oxidized in the following equation and what element is reduced? Oxidation Reduction Reactions CHECK YOUR ANSWER

129 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Integrated Science—Physics

130 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Corrosion and Combustion

131 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Corrosion and Combustion Corrosion The process whereby a metal deteriorates through oxidation-reduction reactions.

132 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Corrosion and Combustion Corrosion The process whereby a metal deteriorates through oxidation-reduction reactions. It can be prevented by coating the metal with zinc, which oxidizes first.

133 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Corrosion and Combustion Combustion An oxidation-reduction reaction between a nonmetallic material, such as wood, and oxygen.

134 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley One of the products of combustion is water. Why doesn’t this water extinguish the combustion? A.While areas of combustion are being extinguished, new areas are combusting. B.Combustion only produces micro amounts of water. C.The chemical combustion reaction is happening too fast for the water to have an effect on the fire. D.This water is in the gaseous phase and merely floats away. Corrosion and Combustion CHECK YOUR NEIGHBOR

135 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley One of the products of combustion is water. Why doesn’t this water extinguish the combustion? A.While areas of combustion are being extinguished, new areas are combusting. B.Combustion only produces micro amounts of water. C.The chemical combustion reaction is happening too fast for the water to have an effect on the fire. D.This water is in the gaseous phase and merely floats away. Corrosion and Combustion CHECK YOUR ANSWER Explanation: Carefully place your hand over a campfire, and you can feel the greater humidity as water vapor escapes.

136 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Reaction Rates Reaction rate: The speed with which products form from the reactants.

137 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Reaction Rates Reaction rate: The speed with which products form from the reactants. Affected by Concentration Temperature Catalyst

138 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Reaction Rates Reaction rate: The speed with which products form from the reactants. Affected by Concentration Temperature Catalyst Premise: Reactant molecules have to make physical contact with each other in order to transform into products.

139 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Reaction Rates Reaction rate: The speed with which products form from the reactants. Affected by Concentration The more concentrated a sample of nitrogen and oxygen, the greater the likelihood that N 2 and O 2 molecules will collide and form nitrogen monoxide.

140 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Reaction Rates Reaction rate: The speed with which products form from the reactants. Affected by Temperature Slow-moving molecules may collide without enough force to break the bonds. In this case, they cannot react to form product molecules.

141 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Reaction Rates Reaction rate: The speed with which products form from the reactants. Affected by Catalysts Reactant molecules must gain a minimum amount of energy, called the activation energy, E act, in order to transform into product molecules.

142 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Reaction Rates Reaction rate: The speed with which products form from the reactants. Affected by Catalysts A catalyst has the effect of lowering the activation energy, which allows for the reaction to proceed at a quicker rate.

143 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Carefully examine the following reaction sequence for the catalytic formation of ozone, O 3, from molecular oxygen, O 2. Which chemical compound is behaving as the catalyst? A. Nitrogen dioxide, NO 2 B.Nitrogen monoxide, NO C.Atomic oxygen, O D.Oxygen, O 2 Reaction Rates CHECK YOUR NEIGHBOR O 2 + 2 NO  2 NO 2 2 NO 2  2 NO + 2 O 2 O + 2 O 2  2 O 3

144 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley O 2 + 2 NO  2 NO 2 2 NO 2  2 NO + 2 O 2 O + 2 O 2  2 O 3 Carefully examine the following reaction sequence for the catalytic formation of ozone, O 3, from molecular oxygen, O 2. Which chemical compound is behaving as the catalyst? A. Nitrogen dioxide, NO 2 B.Nitrogen monoxide, NO C.Atomic oxygen, O D.Oxygen, O 2 Reaction Rates CHECK YOUR ANSWER Explanation: The NO reacts with O 2 to form O, which reacts with O 2 to form O 3. In other words, the NO gets this reaction going. As another clue, note how NO is regenerated after the second reaction.

145 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Exo- and Endothermic Reactions Exothermic reaction: A chemical reaction that results in the net production of energy. reactants products + energy

146 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Exothermic reaction: A chemical reaction that results in the net production of energy. reactants products + energy Endothermic reaction: A chemical reaction in which there is a net consumption of energy. energy + reactants products Exo- and Endothermic Reactions

147 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Exo- and Endothermic Reactions

148 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Use the bond energies below to determine whether the following reaction is exothermic or endothermic: Exo- and Endothermic Reactions CHECK YOUR NEIGHBOR A. Exothermic with more than 50 kJ of energy released. B. Endothermic with more than 50 kJ of energy absorbed. C. Endothermic with less than 50 kJ of energy absorbed. D. Exothermic with less than 50 kJ of energy released. H 2 + Cl 2  2 HCl H-H(bond energy: 436 kJ/mol) Cl-Cl(bond energy: 243 kJ/mol) H-Cl(bond energy: 431 kJ/mol)

149 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Use the bond energies below to determine whether the following reaction is exothermic or endothermic: Exo- and Endothermic Reactions CHECK YOUR ANSWER A. Exothermic with more than 50 kJ of energy released. B. Endothermic with more than 50 kJ of energy absorbed. C. Endothermic with less than 50 kJ of energy absorbed. D. Exothermic with less than 50 kJ of energy released. H 2 + Cl 2  2 HCl H-H(bond energy: 436 kJ/mol) Cl-Cl(bond energy: 243 kJ/mol) H-Cl(bond energy: 431 kJ/mol)

150 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Use the bond energies below to determine whether the following reaction is exothermic or endothermic: Exo- and Endothermic Reactions CHECK YOUR ANSWER A. Exothermic with more than 50 kJ of energy released. B. Endothermic with more than 50 kJ of energy absorbed. C. Endothermic with less than 50 kJ of energy absorbed. D. Exothermic with less than 50 kJ of energy released. H 2 + Cl 2  2 HCl H-H(bond energy: 436 kJ/mol) Cl-Cl(bond energy: 243 kJ/mol) H-Cl(bond energy: 431 kJ/mol) 436 kJ/mol243 kJ/mol 431 kJ/mol

151 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Use the bond energies below to determine whether the following reaction is exothermic or endothermic: Exo- and Endothermic Reactions CHECK YOUR ANSWER A. Exothermic with more than 50 kJ of energy released. B. Endothermic with more than 50 kJ of energy absorbed. C. Endothermic with less than 50 kJ of energy absorbed. D. Exothermic with less than 50 kJ of energy released. H 2 + Cl 2  2 HCl H-H(bond energy: 436 kJ/mol) Cl-Cl(bond energy: 243 kJ/mol) H-Cl(bond energy: 431 kJ/mol) 436 kJ/mol243 kJ/mol 431 kJ/mol

152 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Use the bond energies below to determine whether the following reaction is exothermic or endothermic: Exo- and Endothermic Reactions CHECK YOUR ANSWER A. Exothermic with more than 50 kJ of energy released. B. Endothermic with more than 50 kJ of energy absorbed. C. Endothermic with less than 50 kJ of energy absorbed. D. Exothermic with less than 50 kJ of energy released. H 2 + Cl 2  2 HCl H-H(bond energy: 436 kJ/mol) Cl-Cl(bond energy: 243 kJ/mol) H-Cl(bond energy: 431 kJ/mol) 436 kJ/mol243 kJ/mol 431 kJ/mol 679 kJ/mol (absorbed) 862 kJ/mol (released)

153 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Use the bond energies below to determine whether the following reaction is exothermic or endothermic: Exo- and Endothermic Reactions CHECK YOUR ANSWER A. Exothermic with more than 50 kJ of energy released. B. Endothermic with more than 50 kJ of energy absorbed. C. Endothermic with less than 50 kJ of energy absorbed. D. Exothermic with less than 50 kJ of energy released. H 2 + Cl 2  2 HCl H-H(bond energy: 436 kJ/mol) Cl-Cl(bond energy: 243 kJ/mol) H-Cl(bond energy: 431 kJ/mol) 436 kJ/mol243 kJ/mol 431 kJ/mol 679 kJ/mol (absorbed) 862 kJ/mol (released)  = 862 – 679 = 183 kJ/mol released

154 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Entropy and Chemical Reactions It is the natural tendency of energy to disperse from where it is concentrated to where it is dilute.

155 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Entropy and Chemical Reactions It is the natural tendency of energy to disperse from where it is concentrated to where it is dilute. Examples A hot pan radiates heat

156 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Entropy and Chemical Reactions It is the natural tendency of energy to disperse from where it is concentrated to where it is dilute. Examples A hot pan radiates heat Gasoline combusts into smaller molecules

157 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Entropy and Chemical Reactions It is the natural tendency of energy to disperse from where it is concentrated to where it is dilute. Examples A hot pan radiates heat Gasoline combusts into smaller molecules Marbles bouncing on the floor come to a stop

158 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Entropy and Chemical Reactions It is the natural tendency of energy to disperse from where it is concentrated to where it is dilute. Entropy: The term used to describe the degree to which energy has become dispersed.

159 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Entropy and Chemical Reactions It is the natural tendency of energy to disperse from where it is concentrated to where it is dilute. Entropy: The term used to describe the degree to which energy has become dispersed. Reactions that result in an increase in entropy (energy dispersal) tend to occur on their own.

160 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Which type of chemical reaction leads to a greater dispersal of energy? Entropy and Chemical Reactions CHECK YOUR NEIGHBOR ExothermicEndothermic

161 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Which type of chemical reaction leads to a greater dispersal of energy? Entropy and Chemical Reactions CHECK YOUR ANSWER ExothermicEndothermic

162 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Entropy and Chemical Reactions Exothermic reactions tend to be self-sustaining, because they lead to large increases in entropy.

163 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Entropy and Chemical Reactions Exothermic reactions tend to be self-sustaining because they lead to large increases in entropy. Example: A campfire

164 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Entropy and Chemical Reactions Exothermic reactions tend to be self-sustaining because they lead to large increases in entropy. Endothermic reactions tend to require the continual input of energy. Example: A campfire

165 Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Entropy and Chemical Reactions Exothermic reactions tend to be self-sustaining because they lead to large increases in entropy. Endothermic reactions tend to require the continual input of energy. Example: A campfire Example: Photosynthesis


Download ppt "Copyright © 2007 Pearson Education, Inc., publishing as Pearson Addison Wesley Hewitt/Lyons/Suchocki/Yeh Conceptual Integrated Science Chapter 13 CHEMICAL."

Similar presentations


Ads by Google