1. 8.3 Properties of Acids and Bases

2. Acid
Compound that produces hydronium ions (H3O+) when dissolved in water.
Properties of an acid include:
Sour taste
Ex: different fruits, vinegar. Do not test an acid by tasting it.
Reactivity with metals
Reaction between an acid and a metal is a single replacement reaction.
Ability to turn blue litmus paper red
Proton donor

4. Base
Compound that produces hydroxide ions (OH-) when dissolved in water.
Properties of a base include:
Bitter taste
Slippery feel
Ability to turn red litmus paper blue
Proton acceptor

6. Neutralization and Salts
The reaction between an acid and a base is called neutralization.
The neutralization reaction between an acid and a base produces a salt and water.
-The negative ions in an acid combine with the positive ions in a base to produce an ionic compound called a salt.
-The hydronium ions from the acid combine with the hydroxide ions from the base to produce water.

7. Neutralization and Salts
Table salt is the most common example of a salt compound.

8. 8.4 Strength of Acids and Bases

9. The pH Scale
Scale, numbered 0-14, used by chemists to describe the concentration of hydronium ions in a solution.
pH=7 is neutral
pH < 7 is an acid
pH > 7 is a base
Lower pH=greater H3O+ (hydronium) ion concentration in solution
Higher pH=lower H3O+ (hydronium) ion concentration in solution

12. Strong Acids and Bases
When strong acids dissolve in water, they ionize almost completely.
HCl
Strong bases dissociate (separates into ions as it dissolves) almost completely in water.
Sodium hydroxide

13. Weak Acids and Bases
Weak acids and bases ionize or dissociate only slightly in water.
Weak acid=citric acid in orange juice or acetic acid in vinegar
Weak base=toothpaste and shampoo

14. Buffers Solution that is resistant to large changes in pH.
Made from a weak acid and its salt or a weak base and its salt.
pH of buffers remain relatively constant

15. Electrolytes
Substance that ionizes or dissociates into ions when it dissolves in water.
The resulting solution can conduct an electric current.
Can be classified as strong or weak.
Strong acids and bases are strong electrolytes because they dissociate or ionize almost completely in water.