1. West Valley High School
Chapter 14B Notes
Acids and Bases
West Valley High School
Chemistry
Mr. Mata

2. Standard 5D
Students will understand how acids and bases behave when mixed together.

3. Essential Question
How do acids and bases behave when mixed together into a solution?

4. Acid and Base Properties
Acids produce hydrogen ions (H+) in aqueous (aq) solution.
Aqueous (aq) = dissolved in H2O.
Most bases produce hydroxide ions (OH-) when dissolved in water.
Base exception: ammonia (NH3).

5. Bronsted-Lowry Definitions
And acid is a proton (H+) donor and a base is a proton (H+) acceptor.
Acids and bases always come in pairs.
When HCl dissolves in H2O, gives its proton (H+) to water; acting like an acid.
HCl(g) + H2O(l) H3O+ + Cl-
Water accepts the proton (H+) from water; behaving like a base.

6. Pairs General equation HA(aq) + H2O(l) H3O+(aq) + A-(aq)
This is an equation at equilibrium.
There is a balance with one reactant acting like an acid and the other reactant behaving like a base.

7. pH pH scale 0-14 range. pH = “power of hydrogen”.
Base 10 scale (logarithmic scale).
“[ ]” = concentration or molarity.
pH= -log[H+]
Used because [H+] is usually very small
[H+] = 1.0 x pH= 7.00 (neutral).

8. Relationships pH= -log[H+] pOH= -log[OH-] pH + pOH = 14.00
[H+][OH-] = 1.0 x10-14
[H+],[OH-],pH and pOH Given any one of these we can find the other three.

9. 100
10-1
10-3
10-5
10-7
10-9
10-11
10-13
10-14
[H+] 1 3 5 7 9 11 13 14 pH
Acidic
Neutral
Basic 1 3 5 7 9 11 13 14
pOH
Basic
100
10-1
10-3
10-5
10-7
10-9
10-11
10-13
10-14
[OH-]

10. Strong Acids HCl, HBr, HI, HNO3, H2SO4, HClO4 Completely dissociated.
90% or higher dissociation.

11. Weak Acids HC2H3O2 (acetic acid = vinegar). Partially dissociated.
0% to 35% dissociation.

12. Bases The OH- is a strong base.
Hydroxides of the alkali metals are strong bases because they dissociate completely when dissolved.

13. Salts as acids and bases
Salts are ionic compounds.
Salts of the cation of strong bases and the anion of strong acids are neutral.
Examples: NaCl, KNO3

14. Chapter 14B SUTW Prompt
Describe how strong acids and bases differ from weak acids and bases.
Complete a sentence paragraph using the SUTW paragraph format. Hilight using green, yellow, and pink.
Due Date: Tuesday, February 13, 2018 (start of class).