1. Wednesday, October 22nd , 2014
Objective: to identify acids and bases by ph level. Warmup: 1.) When sugars are broken down to produce usable energy for cells, a large amount of heat is released. Explain how the water inside your cells helps to keep the cell’s temperature constant. Hint: Look at the back of your water packet.

2. ACIDS AND BASES

3. acids and bases

4. (hydrochloric acid added to water produces hydrogen and chlorine)
1. ACID – any substance that gives off hydrogen ions (H+) to a
solution.
Example: HCl (hydrochloric acid) found in your stomach
HCl + H2O  H+ + Cl-
reactants products
(hydrochloric acid added to water produces hydrogen and chlorine)

5. (sodium hydroxide added to water produces sodium and more water)
BASE
2. BASE – any substance that removes hydrogen ions (H+) from a
solution.
Does this by adding hydroxide ions (OH-) to H+ to form water (H2O)
Example: NaOH (sodium hydroxide)
NaOH + H2O  Na+ + H2O
reactants products
(sodium hydroxide added to water produces sodium and more water)

6. PH Scale
3. pH SCALE – measure of how acidic or basic a solution is

7. PH Scale 3. pH SCALE – measure of how acidic or basic a solution is
Acids = pH < 7 (more H+ than OH-)
Bases = pH > 7 (more OH- than H+)
Neutral = pH = 7 (equal amounts of H+ than OH- )
Each pH unit represents a 10x change in concentration of H+ ions
Example: pH 2 = 10x more H+ than pH 3
pH 2 = 100x more H+ than pH 4

8. PH Scale
4. Buffers– substances that cause a solution to resist pH changes
Does this by donating/accepting H+ ions
Keeps body fluids stable and allows them to maintain homeostasis
Example: enzymes can clot blood & break down food
white blood cells can make antibodies
red blood cells can carry oxygen in the blood