Chapter 18: Acids, Bases, and Salts
18.1: Defining Acids and Bases
- Acid
- A substance that increases the concentration of hydrogen ions (H⁺) in an aqueous solution.
- Base
- A substance that increases the concentration of hydroxide ions (OH⁻) in an aqueous solution.
- Electrolyte
- Any substance that produces ions in solution, allowing it to conduct electricity.
- Neutralization Reaction
- A chemical reaction between an acid and a base that produces water and a salt.
Observable Properties
- Acids
-
- Taste sour
- Conduct electricity (electrolytes)
- React with metals to produce hydrogen gas
- Turn litmus paper red
- Neutralize bases
- Bases
-
- Taste bitter
- Feel slippery
- Conduct electricity (electrolytes)
- Turn litmus paper blue
- Neutralize acids
Acid-Base Models
- Arrhenius Model
- Classifies acids as substances that release H⁺ ions and bases as substances that release OH⁻ ions in aqueous solutions.
- Brønsted-Lowry Model
- Defines acids as proton donors and bases as proton acceptors.
- Lewis Model
- Defines acids as electron pair acceptors and bases as electron pair donors.
Example: Neutralization Reaction
The reaction of sulfuric acid (H₂SO₄) with sodium hydroxide (NaOH) produces sodium sulfate (Na₂SO₄) and water (H₂O).
Questions for Students
- List the observable physical and chemical properties of acids and bases.
- Explain the differences between the Arrhenius, Brønsted-Lowry, and Lewis models of acids and bases.
- Provide an example of a neutralization reaction and describe the products formed.
- What is the role of electrolytes in acids and bases?
- Describe how acids and bases affect litmus paper.