1. ACIDS, BASES, & SALTS
Chapter 17

2. ACIDS
ACID:
An acid is a substance that produces Hydrogen ions (H+) in a solution.
Properties of ACIDS
They are electrolytes (conduct electricity)
They are Corrosive
They Taste Sour
IMPORTANT – Never use taste to test for an acid*

3. BASES
Bases:
A base is a substance that produces hydroxide ions (OH-) in a solution.
Properties of Bases:
They are electrolytes
They are corrosive (caustic)
They feel slippery
They have a bitter taste
IMPORTANT – taste should never be used to test for a base*

4. Strength of Acids & Bases
The STRENGTH of an Acid or Base depends on how completely a compound is broken apart to form ions when dissolved in water
The CONCENTRATION of an Acid or Base refers to the amount of an Acid or Base in a solution. *

5. Strength vs. Concentration
The size of the dot represents how completely the compound is broken apart to form H+ ions: The Strength of the Acid.
-Acid A
-Acid B
Even though Acid B is stronger than Acid A, Acid A has a higher concentration: A larger amount of the acid in its beaker.

6. Ions Ions are atoms that have either a positive or negative charge.
pH measures the concentration of hydronium ions (H3O+)in a solution
What is a Hydronium ion?
Hydronium ions (H3O+) form when Hydrogen ions (H+) bond with water*
H+ + H2O
H3O+

7. pH pH’s of less than 7 are - Acidic pH’s of greater than 7 are - Basic
pH of exactly 7 is -
Neutral

8. Finding the pH To determine the pH of something, Use:
pH paper – has a plant extract that changes color at different pH levels.
pH meter – detects how easily electricity can flow through the solution. *

9. Salts
A Salt is a compound formed when negative ions from an acid bond with the positive ions of a base
Salts form through the process of Neutralization.
When Acids and Bases are added together (or Neutralized) their ions form: Salt and Water*

10. Example: Neutralization of Hydrochloric Acid and Sodium Hydroxide
H2O
HCl- + NaOH+
H3O+ + Cl- + Na+ + OH-
Water forms:
H3O+ + OH-
2H2O
Salt forms:
Na+ + Cl-
NaCl
What kind of Change is taking place, – Physical or Chemical?*