1. Acid-Base Properties and Theories
Chemistry 12/12AP

2. Properties of Acids Sour taste
Turn blue litmus red (and other indicators)
Neutralize bases
Conduct electricity (electrolytes)
React with active metals (group I, II) to produce H2 gas
React with metal oxides to produce a salt of the metal and water
Produce H+ or H3O+ in solution (see acid-base theories)
pH less than 7

3. Properties of Bases Bitter taste ex. tonic water (quinine)
Turn red litmus blue (and other indicators)
Neutralize acids
Conduct electricity (electrolytes)
Feel slippery (soapy)
pH greater than 7
Produce OH- in solution

4. Arrhenius Theory
An Acid is a substance that produces H+ ions in solution. A base is a substance that produces OH- ions in solution. Neutralization occurs when H+ ions combine with OH- ions to form water.

5. Acid or Base (Arrhenius Style)
H2SO4
Ca(OH)2
Pb(NO3)2
NaHCO3
NaOH
HBr

6. Limitations of Arrhenius Theory
Acids (like HCl) are able to be neutralized by NaOH and NH3.
Not all bases have OH- ions, NH3 in H2O does, but, if NH3 reacts as a gas with HCl gas, NH4Cl is still formed, but is not a solution, so this theory won’t always work.

7. Bronsted-Lowry Theory
An acid is a proton donor.
A base is a proton acceptor.
H3O+ is a hydronium ion (aka. THE PROTON)
H2O is the base.
HCl is the acid

8. Writing Conjugates
See Board notes

9. Conjugate Acid-Base Pairs
A conjugate acid is the substance that has accepted the proton (gained an H+) A conjugate base is the substance that has lost the proton. Each acid has a conjugate base and each base has a conjugate acid.

10. Formation of Acids
Acids are formed when a non-metal oxide is dissolved in water (forms an oxyacid)
SO2 + H2O  H2SO3

11. Acid Nomenclature

12. Formation of Bases
Formed when a metal oxide reacts with water (forms a strong base)
Na2O + H2O 2NaOH

13. Relative Strengths of Acids and Bases

14. Strong Acids & Bases
Strong acids – hydrogen halides, oxyacids of halogens, sulfuric acid & nitric acid
Strong bases – NaOH, KOH, Cs(OH)2, Ca(OH)2
Both of these ionize completely in H2O.

15. Weak Acids & Bases
Weak acids and bases do not ionize completely in water
A weak acid/base will be shown with a double arrow reaction, and also have small Ka and Kb values

16. Self-ionization of Water

17. Ionization Constants Acid ionization constant (Ka)
Base ionization constant (Kb)
Magnitude dictates the strength of the acid
Strong acids have large Ka values – this means that they dissociate completely (100%) 
Weak acids have small Ka values – and do not dissociate completely (usually 5% or so) 
Magnitude dictates the strength of the base
Strong bases have large Kb values – and dissociate completely (100%) 
Weak bases have small Kb values - and do not dissociate completely (5% or so) 

18. Ion Product of Water (Kw)
Kw = 1.0 x 10-14=[H+][OH-] – changes with temperature
Kw = Ka x Kb
Uses: Can find concentration of OH- or H+, the Kb of the conjugate base (and vice versa), or used with pH or pOH calculations when necessary

19. pH and pOH
pH = -log10[H+] or pH = -log10[H3O+] (same thing) [H+] = 10-pH pOH = -log10[OH-] [OH-] = 10-pOH

20. pH Scales

21. Ionization Constants of Weak Acids & Bases

22. Equilibrium Problems Using Acids
Type 1: Solving for Ka You must have the following: - the equation for the reaction - the equilibrium expression - the concentrations at equilibrium (ICE chart) - The concentrations at equilibrium are usually found with pH or a % ionization.

23. Equilibrium Problems Using Acids
Type 2. Solving for EQ amounts You must have the following: - the reaction - the equilibrium expression and Ka value - the initial concentration of the acid (in mol/L) - With this type, it may ask for the pH at equilibrium