1. 2.4 The pH Scale: Acids and Bases
Unit 2: Biochemistry
2.4 The pH Scale: Acids and Bases

2. Acids and Bases
A small fraction of water molecules can be broken down into hydrogen ions and hydroxide ions

3. Acids
Acid: Forms when a compound dissolves in water creating hydrogen ions
Acids have higher concentrations of hydrogen ions
Acids taste sour and react with metal to form hydrogen gas

4. Bases
Base: Forms when a compound dissolves in water creating hydroxide ions
Bases have a higher concentration of hydroxide ions.
Bases taste bitter and feel slippery/slimy to the touch

5. The pH Scale
The pH scale is based on the concentration of hydrogen ions in solutions.
All solutions have a PH between 0-14.
Water’s PH is 7-Neutral.
Acids have a PH below 7, Bases have a PH above 7.
Based on a factor of 10.
A solution with a pH of 5 has 10 times more hydrogen ions than a solution with a pH of 6

6. Label:
Acidic
Basic
Neutral

8. Brain Break: Gotchya!