1. Drill pd 4A 5/20/2015 What do you do if you spill acid in the lab?
Do you add acid to water or water to acid?

2. Drill pd 3 5/19/15 What do you do if you spill acid in the lab?
Tell your instructor immediately
Place baking soda (base) over it to neutralize and clean up with paper towels.
Do you add acid to water or water to acid?
Acid to water

3. Objectives SWBAT: Define acid rain and it’s effects on our environment
list major differences between acids and bases
list products of neutralization reactions
distinguish between 2 methods of defining acids and bases.
list properties of a salt

4. Agenda
Notes on Acids and Bases (50 mins)
Worksheets

5. Acid Rain
Look at the following pictures on the powerpoint. From the pictures and your own experiences, what are some of the damaging effects of acid rain?

8. Acids and Bases

9. Properties of Acids (in aq solution)
Sour taste
Low pH
Turn blue litmus paper red
Conduct electrical current

10. Properties of Bases (in aq solution)
Bitter taste
Slippery
High pH
Turn red litmus paper blue
Conduct electrical current

11. What happens when Mg reacts with HCl??
Hydrogen gas is produced (popping noise we heard in earlier lab)

12. Indicators
Substance that turns 1 color in acidic solutions and another in basic solutions.
Examples: phenolphthalein (used in bio) and litmus paper (made from a species of lichen)

13. Acid-Base Reactions
Known as a neutralization reaction. Acids and bases will react with each other to form salt and water.
A B  Salt + H2O
HCl + NaOH  NaCl + H2O

14. Characteristics of Salts
Electrolytes
Ionic compounds
High melting points
Products of neutralization

15. Arrhenius Definition
Acid = substance that releases H+ ions in aq solution
HCl  H+ + Cl-
Base = substance that releases OH- ions in aq solution
NaOH  Na+ + OH-
Neutralize each other: H+ + OH-  H2O

16. Bronsted-Lowry Definition
As more and more substances were determined to have acidic or basic properties, even some without obvious H+ or OH-, a new definition was needed.
Acid = proton donor
Base = proton acceptor

17. Bronsted-Lowry Definition
Acid = proton donor
H2O + HCl  H3O+ + Cl-

18. Bronsted-Lowry Definition
Base = proton acceptor
NH3 + H2O  NH4+ + OH–

19. Drill - pd 3 5/20/15 Identify the following as acid or base.
HBr + H20  H30+ + Br-
Write balanced neutralization equations for the following reactants:
HBr and NaOH
H2SO4 and NH4OH
H2CO3 and NaOH

20. Answers to Drill HBr + NaOH ------> NaBr + H2O
The reaction of an acid and a base results in the formation of a salt and water. The process is known as neutralization.
HBr + NaOH > NaBr + H2O
H2SO4 + 2 NH4OH > (NH4)2SO4 + 2H2O
H2CO3 + 2 NaOH --> Na2CO3 + 2 H2O

21. Announcement
Pass forward Lab Notebooks please.

22. Agenda Go over Acid Base WS Homework: Conjugate Acids and Bases WS
Naming Acids WS

23. When water gains a proton it is called HYDRONIUM.
H3O+

24. When water loses a proton it is called HYDROXIDE.
OH-

25. Acids & Bases Review Acid Base
substance that releases H+ ions in aq solution
Proton donor
Base
substance that releases OH- ions in aq solution
Proton acceptor

26. H2O is both an acid and a base
Water is simultaneously donating and accepting protons = amphoteric substance

27. Conjugate Acids & Bases
Conjugate acid – what is produced when a base gains a H+ ion
Conjugate base – what is produced when an acid loses a H+ ion
Conjugate base pair – two substances related to each other by the donating and accepting of a single
H+ ion

28. Conjugate acid-base pairs
HF + H2O H3O + F –
acid base conjugate conjugate
acid base

29. Conjugate Pairs Inverse Relationship
The stronger the acid, the weaker its conjugate base
The stronger the base, the weaker its conjugate acid
HCO3 + H2O  H3O + CO3
weak A strong B weak strong C.A. C.B.

30. Naming Acids 1. Binary – contains hydrogen & one other element
Start with hydro-
Then element
End with –ic acid
Ex. HCl = hydrochloric acid
HBr = hydrobromic acid

31. Naming Acids
2. Oxyacids – Contains both hydrogen & oxyanion = polyatomic ion containing one or more oxygen atoms (NO2, SO4)
If anion ends in –ate then the acid ends
in –ic
“I ate something, and now I am sick”
If the anion ends in –ite then the acid ends in –ous
Ex. HNO2 = nitrous acid, HNO3 = nitric acid

32. Your Turn Name the following acids and bases: HClO3 H2SO3 NaOH NH4OHHI

33. Your Turn Name the following acids and bases: HClO3 – chloric acid
H2SO3 – sulfurous acid
NaOH – sodium hydroxide
NH3OH – ammonium hydroxide
HI – hydroiodic

34. Nitric acid
Hydrochloric
Sulfuric acid
Sulfurous acid
Acetic acid
Hydrobromic acid
Nitrous acid
Phosphoric acid
Hydrosulfuric
Carbonic acid

35. Homework
Conjugate Acid-Base Pairs WS

36. Acid Strength
A stronger acid will react completely to form ions (strong electrolytes) and hydronium ions (H3O+) in water.
Hydrochloric acid (all HCL molecules are ionized into hydronium and chloride ions)
HCl + H2O  H3O+ + Cl-
Acetic Acid (not all A.A. molecules are ionized into hydronium and ions)
CH3COOH + H2O  H3O+ + CH3COO-

37. Examples of Strong & Weak Acids
Strong Weak HCl CH3COOH HBr H2CO3 H2SO4 HClO

38. Objectives
SWBAT compare the strength of a weak acid with the strength of its conjugate base
SWBAT explain the relationship between acid and base strength and the values of their ionization constants.

39. Base Strength
A strong base has the strongest affinity for H+ ions and dissociates entirely into metal ions and OH-.
For ex. Calcium oxide (CaO); oxygen strongly attracts H+ ions.
Strong bases: CaO, NaOH, KOH
Weak base: ammonia (NH3)

40. Conjugate Pairs Inverse Relationship
The stronger the acid, the weaker its conjugate base
The stronger the base, the weaker its conjugate acid
HCO3 + H2O  H3O + CO3
weak A strong B weak strong C.A. C.B.

41. Sample Problem
Write an equation to show the dissociation of hydrochloric acid in water.

42. Answer
HCl + H2O → H3O+ + Cl−
HCl is a STRONG ACID

43. Sample Problem
Write an equation to show the dissociation of the hydrogen carbonate ion in water.

44. Answer HCO3 + H2O  H3O+ + CO3-
The hydrogen carbonate ion (HCO3-) is a WEAK ACID

45. How can the strength of an acid or base be quantified?
Measure the amount of hydronium ions created (acids) or the amount of hydroxide ions created (bases)
by calculating dissociation constants.

46. Acid Dissociation Constant
HA + H2O  H3O+ + A-
HA = acid (H = hydrogen, A = rest of acid molecule
A = rest of acid after H+ is removed
[ ] = concentration
Ka = [H3O +] [A-]
[HA]

47. Acid Dissociation Constant
For HClO2, show the dissociation Rx and write the expression for it in terms of Ka
HClO2 + H2O  ClO H3O+
Ka = [H3O +] [A-] Ka = [H3O +] [ClO2 -]
[HA] [HClO2]

48. Your Turn
For HNO2 show the dissociation Rx and write the expression for it in terms of Ka
HNO2 + H2O  NO H3O+
Ka = [H3O +] [A-] Ka = [H3O +] [NO2 -]
[HA] [HNO2]

49. Acid Dissociation Constant
The larger the dissociation value, the more the acid reacts with water to produce hydronium ions, therefore the stronger the acid
Weak acids have values less than 1 (only small fraction of acid molecule dissociates in water)

50. Base Dissociation Constant
B + H2O  HB+ + OH-
B = base
HB = B after H+ is added
[ ] = concentration
Kb = [HB+] [OH-]
[B]

51. Base Dissociation Constant
For C6H13NH2, show the dissociation Rx and write the expression for it in terms of Ka
C6H13NH2 + H2O  C6H13NH3+ + OH -
Kb = [HB+] [OH-] Kb = [C6H13NH3+][OH-]
[B] [C6H13NH2]

52. Your Turn
For HSO3-, show the dissociation Rx and write the expression for it in terms of Ka
HSO3- + H2O  + H2SO3 + OH -
Kb = [HB+] [OH-] Kb = [H2SO3 ] [OH-]
[B] [HSO3- ]

53. Base Dissociation Constant
The stronger the base, the larger the concentration of OH- ions and the larger the Kb.
Weak bases have a Kb less than 1.

54. Acid & Bases Lab: Litmus Test
Predict if substance is acidic, basic or neutral and record in 2nd column of WS.
Show me your predictions before going to lab.
Test the 18 substances using red and blue litmus paper. Record your results in columns 3 & 4 of table by placing a  under a category if acidic or basic. If no reaction, no . Place used litmus papers on paper towel on top of runway.
Show me your work before conducting pH test.

55. Acid & Bases Lab: pH Test
For each substance, record the color that the pH paper changed to after you dipped it into the solution.
Record the pH value that matches with the color on the pH paper.

56. Assignment 18-2 Review and Reinforcement – due tomorrow. Cross out #9.
Cross out Practice Probs on the back – not required to do these types of problems!

57. What is concentration?
Using molarity, it is a measure of moles of solute in liters of solution.
Concentration is measured in WATER!

58. Question
Who is taking an AP test next week and when?

59. Homework DUE
Titration Lab

60. Announcements Review – two worksheets
Test – May 16 (4B) or May 19 (4A)

61. Agenda Review Titration Problems Finish up Acids and Bases
Review Sheet 1
Review Sheet 2

62. Homework
Titration Practice – front side only
Review Worksheets

63. Test Topics Properties of acids, bases, and salts
Bronsted-Lowry definition of acids/bases
Lewis definition of acids/bases
Amphoteric substance
Neutralization reaction – must be balanced
Naming acids
Calculating pH, pOH, [H+], and [OH-]
Titration calculations

64. Lewis Definition of Acids/Bases
Lewis Acid – something that accepts an electron pair to form a covalent bond
Lewis Base – something that donates an electron pair to form a covalent bond
A + :B → A—B

65. Announcement
Make up Titration Lab and Help available afterschool today.

66. Agenda/Announcements
Acids and Bases Quest postponed until tomorrow.
Make-up date = Monday, May 21.
Go over Acids and Bases Review Sheet
Hand in Titration Lab Calculations

67. Drill # /17/12
Write the balanced neutralization equations for the following reactions:
1. carbonic acid & calcium hydroxide
2. potassium hydroxide and acetic acid
3. barium hydroxide and hydrochloric acid

68. What are the ion concentrations in water?
The concentrations of H3O+ and OH- in pure water are each 1.0×10-7 mol/L at 25ºC.
Putting a symbol in brackets is used to signify the concentration.
[H30+] = 1.0×10-7 M
[OH-] = 1.0×10-7 M

69. Ionization Constant of water, KW
KW = [H30+] [OH-]
KW = (1.0×10-7)(1.0×10-7) = 1.0×10-14

70. Bases increase the [OH-]
Acids increase the [H30+] Whenever [H30+] is greater than [OH-], the solution is acidic.
Bases increase the [OH-]
Whenever [OH-] is greater than [H30+], the solution is basic.
With an increase in [H30+], some of the H30+ ions will react with the OH- ions, reducing [OH-] . [H30+][OH-] will still = 1.0x10-14

71. Concentration values tend to be small…so we use a more convenient scale. pH!

73. pH + pOH = 14
pH – A measure of the acidity of a solution.
It is the negative logarithm of the hydronium ion [H30+] concentration.
pH = -log [H30+]

74. pH + pOH = 14
pOH – A measure of how basic a solution is.
It is the negative logarithm of the hydroxide [OH-] concentration.
pOH = -log [OH-]

75. The logarithm scale is created to make numbers over a large range more manageable.

76. The logarithm base 10 of a number x is the power to which 10 must be raised in order to equal x.
Log 10 x = ? Log 100 = ?
10? = x 10 ? = 100

77. Remember, our concentrations are SMALL
Remember, our concentrations are SMALL. So we are going to be dealing with decimals…
Log 10 x = ? Log .001 = ?
10? = x 10 ? = .001

78. [H+] = 1×10-3 = 0.001
pH = -log [H+]
pH = -log (1×10-3)
pH = 3
To determine pH from a concentration where 1 is the only digit, write the concentration in scientific notation. The absolute power of the exponent will be the pH.

79. For a base, you do the same thing except remember that you are solving for pOH first…

80. Ionization Constant of water, KW
KW = [H30+] [OH-]
KW = (1.0×10-7)(1.0×10-7) = 1.0×10-14

81. 11 3.0 2.0 12 8 6 10.8 3.22 13 .70 2.22 11.8 Solutions [H+] pH [OH-]
pOH
1.0×10-3M HClO4
0.010 M HCl
M KOH
6.00×10-4 HBr
0.20 M NaOH
H2SO4 11
3.0
1.0×10-3M
1.0×10-11M
2.0 12
1.0×10-2M
1.0×10-12M 8 6
1×10-8M
1×10-6M
10.8
3.22
6.00×10-4M
1.67×10-11M 13
.70
5.0×10-14M
2.0×10-1M
2.22
11.8
6.00×10-3M
1.67×10-12M

82. Drill – 5/12/11
Calculate the hydronium ion concentration in a M solution of NaOH.
What is the pH?

83. Green Workbook
Pg. 262 #2
Pg. 264 #1
Pg. 267 #3
Pg. 269 #1 & #2
Pg. 270 #7

84. [H30+] [OH-] = 1.0×10-14 M pH + pOH = 14 pH = -log [H30+]
Equations to Know!!
[H30+] [OH-] = 1.0×10-14 M
pH + pOH = 14
pH = -log [H30+]
pOH = -log [OH-]
[H30+] = 10-pH
[OH-] = 10-pOH

86. Drill – 5/9/11
Write the equation for the neutralization reaction between carbonic acid (H2CO3) and calcium hydroxide.

87. Agenda Gallery Walk – record notes from posters on Guided Notes sheet.
Stay out of lab area
Topics include:
Props of acids and bases
Arrhenius definition of an acid and a base
Bronsted-Lowry definition of an acid and base
Determining the strength of acids and bases
Acid dissociation constant
Naming and Identifying acids and bases

88. Drill 54 – 5/2/2012
What do you think are properties of acids? Of bases?

89. Drill #57 5/7/2012 Do you add acid to water or water to acid? AAA
Always Add Acid to water AW

90. Drill #63 5/15/12
A solution of KOH is titrated with HCL. The pH is measured as the HCl is added to the flask. The value of the pH will
Please be patient with me today, I barely have a voice!

91. Drill #63 5/15/12
A solution of KOH is titrated with HCL. The pH is measured as the HCl is added to the flask. The value of the pH will decrease.

92. Homework Due
Naming Acids WS

93. Assignment
Bronsted-Lowry Acids & Bases WS
Titration Curve Data Graph

94. Drill #9 5/5, 5/6/2014

95. Homework Due
Bronsted-Lowry Acids & Bases WS
Keep Titration Graph