1. ACIDS AND BASES

2. Ga Standards
Students know the observable properties of acids, bases, and salt solutions.
Students know acids are hydrogen-ion donating and bases are hydrogen-ion accepting substances.
Students know strong acids and bases fully dissociate and weak acids and bases partially dissociate.
Students know how to use the pH scale to characterize acid and base solutions.

3. Do Now: Name the following: H3P HBrO3
Create a compound from these names:
Hydrogen Sulfur Acid
Hydrofluoric Acid
Sulfurous Acid
Persulfuric Acid

4. Using any reputable resources on-line, complete the following:
A T-chart comparing the properties of acids and bases
Describe the difference between a Bronsted-Lowry Acid and Base versus an Arrhenius Acid and Base
Fill in the blanks:
Acids turn litmus paper _______________
Bases turn litmus paper _______________
Weak Acids are ___________________________
Strong Acids are __________________________
Weak Bases are ___________________________
Strong bases are ___________________________
Sketch and Label a titration apparatus—explain the titration process—including the terms (equivalence point, end point, indicator, phenolphthalein, and titration)

5. Some Resources General Acid-Base Information
Acid-Base Tutorial & Problems
Properties of Acids & Bases
Bronsted-Lowry Acids and Bases
Arrhenius Acids and Bases
pH Information
Strong vs. Weak Acids
Strong vs. Weak Bases
More pH Info w/ animations
pH Animation
Acid Base Indicators#1
Acid Base Indicators#2
Searchable Acid Base FAQ database
Titration Apparatus
Titration Process

6. Properties of Acids Acids are proton (hydrogen ion, H+) donors
Acids have a pH lower than 7
Acids taste sour
Acids effect indicators
Blue litmus turns red
Methyl orange turns red
Acids react with active metals, producing H2
Acids react with carbonates
Acids neutralize bases

7. Acids are Proton (H+ ion) Donors
Strong acids are assumed to be 100% ionized in solution (good H+ donors).
HCl
H2SO4
HNO3
Weak acids are usually less than 5% ionized in solution (poor H+ donors).
H3PO4
HC2H3O2
Organic acids

8. Acids Have a pH less than 7

9. Acids Taste Sour
Organic acids are weak acids. Some are used as flavoring agents in food.
Citric acid in citrus fruit
Malic acid in sour apples
Lactic acid in sour milk and sore muscles
Butyric acid in rancid butter

10. Organic Acids
Organic acids all contain the “carboxyl” group, sometimes several of them.
The carboxyl group is a poor proton donor, so ALL organic acids are weak acids.

11. Acids Effect Indicators
Blue litmus paper turns red in contact with an acid.
Methyl orange turns red with addition of an acid

12. Acids React with Active Metals
Acids react with active metals to form salts and hydrogen gas.
Mg + 2HCl  MgCl2 + H2(g)
Zn + 2HCl  ZnCl2 + H2(g)
Mg + H2SO4  MgSO4 + H2(g)

13. Acids React with Carbonates
2HC2H3O2 + Na2CO3
2 NaC2H3O2 + H2O + CO2

14. Effects of Acid Rain on Marble (calcium carbonate)
George Washington:
BEFORE
George Washington:
AFTER

15. Acids Neutralize Bases
Neutralization reactions ALWAYS produce a salt and water.
HCl + NaOH  NaCl + H2O
H2SO4 + 2NaOH  Na2SO4 + 2H2O
2HNO3 + Mg(OH)2  Mg(NO3)2 + 2H2O

16. Properties of Bases Bases are proton (hydrogen ion, H+) acceptors
Bases have a pH greater than 7
Bases taste bitter
Bases effect indicators
Red litmus turns blue
Phenolphthalein turns purple
Solutions of bases feel slippery
Bases neutralize acids

17. Bases are Proton (H+ ion) Acceptors
Sodium hydroxide (lye), NaOH
Potassium hydroxide, KOH
Magnesium hydroxide, Mg(OH)2
Calcium hydroxide (lime), Ca(OH)2
OH- (hydroxide) in base combines with H+ in acids to form water
H+ + OH-  H2O

18. Bases have a pH greater than 7

19. Bases Effect Indicators
Red litmus paper turns blue in contact with a base.
Phenolphthalein turns bright pink in a base.

20. Bases Neutralize Acids
Milk of Magnesia contains magnesium hydroxide, Mg(OH)2, which neutralizes stomach acid, HCl.
2 HCl + Mg(OH)2
MgCl2 + 2 H2O

21. pH Calculations
SPECIAL NOTE: In pH chemistry, H+ is often used as an abbreviation for H3O+! ! ! ! ! ! ! ! !
Soren Sorensen

22. pH Scale

23. Self-Ionization of Water
H2O + H2O  H3O+ + OH-
Though pure water is considered a non-conductor, there is a slight, but measurable conductivity due to “self-ionization”

24. Kw – Ionization Constant for Water
In pure water at 25 C:
[H3O+] = 1 x 10-7 mol/L
[OH-] = 1 x 10-7 mol/L
Kw is a constant at 25 C:
Kw = [H3O+][OH-]
Kw = (1 x 10-7)(1 x 10-7) = 1 x 10-14

25. Relationship between pH and pOH
Calculating pH, pOH
pH = -log10(H3O+)
pOH = -log10(OH-)
Relationship between pH and pOH
pH + pOH = 14
Finding [H3O+], [OH-] from pH, pOH
[H3O+] = 10-pH
[OH-] = 10-pOH

26. pH + pOH = 14