1. Acids, Bases and pH scale

2. ACIDS
Compound that releases Hydrogen ions (H+)

3. Examples of Common Acids
Hydrochloric acid – HCl
Hydrosulfuric acid – H2SO4
Nitric acid – H2NO3
What do these formulas have in common?

4. Acetic Acid - Vinegar HC2H3O2

5. Lactic Acid
Found in foods like yogurt and
cottage cheese and sourdough bread
Causes muscle soreness

6. Citric Acid Found abundantly in citrus fruits
(lemons, oranges, grapefruit)
Used to add a sour taste to foods
Flavoring in soft drinks

7. Formic Acid
In the venom of ants and bees
HCO2H

8. Amino Acids
“Building blocks” of protein molecules

9. Bases Bases are compounds that release Hydroxide ions (OH -) in water.
Also called alkalines.

10. Examples of Common Bases
Sodium hydroxide – NaOH
Calcium hydroxide – CaOH
Magnesium hydroxide – Mg(OH)2
Most soaps and detergents are basic

11. All compounds are either Acids, Bases, or Neither
Chemical Formula Acid Base Neither HF
H2SO4
CaOH
Mg(OH)2
C6H12O6
HCl
NaCl
Al(OH)2

12. pH
The measurement of the amount of
H+ (hydrogen ions) in solution

13. pH Scale - Range is __

15. Determining a compound’s property from its pH value
pH Acid Base Neutral
Determining a compound’s property from its pH value
1.3
11.47
7.001
0.1
6.999
3.89
13.0
0.0

16. Most living things must live in an environment of
pH 6.5 – 7.5
HOWEVER, there are some exceptions:
Acidophiles – bacteria that live in highly acidic environments. They have evolved a variety of specialized mechanisms to maintain their intracellular pH at a constant level (usually 7.2).
Example: L. acidophilus breaks down food in the intestine

17. Specialized cells in stomach lining make HCl “stomach acid” of pH 1
Parietal Cells

18. Azalea plants thrive in acidic soil of pH 4.5

19. Soil pH
Alkaline soil makes hydrangeas pink

20. Acidic soil makes hydrangeas blue

21. Buffers Help prevent any large changes in pH
Buffers are molecules that can bind to an H+ ion when the H+ concentration increases - “locks” it up so the solution doesn’t get more acidic
Releases an H+ ion when the H+ concentration decreases

22. Blood pH and Buffers Normal pH of blood between 7.35 - 7.45
Less than 6.8 or greater than 7.8 is deadly
Buffers in blood help prevent any large change
in blood pH

23. Lysergic acid diethylamide