1. pH: Another Chemical Property

2. Let’s talk about water. 70% of Earth is covered in water
100% of living things have water in them
Water is a necessity of life

3. + + H H O _

4. Water Dissociates constantly
Breaks apart
2 pieces:
Hydroxide Ion
Hydrogen Ion + H+
Water
OH-

5. H+ vs. OH-
Pure water:
H+ = OH-
Acids:
H+ > OH-
Bases
H+ < OH-

6. pH Scale Measures the strength of acids and bases
How much H+ is in a substance
Created in early 1920 by Soren Sorenson
To help the beer brewing industry
Hydrogen Potential

7. pH Scale
Range is 0-14
Each step is a 10X difference
Fresh water

8. Acids vs. Bases: Bases Acids Anything less than a 7.0 More H+ ions
The more H+ ions the stronger the acid
Taste sour
Corrosive
To metals and living things
Turn litmus paper Red
Examples:
HCl, fruits, sodas, battery acids
Anything more than 7.0
More OH- ions
The more OH-, the stronger the base
Taste bitter, chalky
Cause burns
Turns litmus paper blue
Examples:
Soaps, cleaners, ammonia

9. Determining pH: Indicators: Change colors when acids or base is added
Examples:
pH paper
Litmus paper
Red cabbage

10. Combining Acids and Bases:
Neutralization Reaction
Brings mixture’s pH to 7.0
Ex.
pH 3 added to pH 11 will lead to 7.0
Forms Salts and water
+ Salt

11. Combining Acids and Bases:
In you:
Stomach pH is 4.5
After eating drops to a 1-2
Can cause indigestion
Antacids
Raise pH up to normal
HOW?

12. Acids
Bases

13. 1 2 3 4 5 6
Baking Soda
Tap Water
Table Cleaner
Ammonia
Lemon Juice
Soda
Vinegar
coffee
Egg
Saliva