1. Chapter 8
Acids and Bases

2. What are acids and bases?
Lemons, grapefruit, vinegar, etc. taste sour because they contain acids.
Acid in our stomach helps food digestion
Acid from bacteria turn milk sour and are used to make yogurt and cheese.
Bases neutralize acids (pH = 7)
Antacids are taken to offset the effect of too much acid in the stomach.
Other examples are drain cleaners and oven cleaners.
pH of a solution describes its acidity. Major changes in pH of the body fluids can severely affect biological activities within the cells. Therefore buffers are present to prevent large fluctuations in pH.

83. CO2 + H2O  H2CO3  H3O+ + HCO3-
Buffers in the Blood
Cells can only function properly when the pH is between 6.8 – 8.0.
The normal pH of arterial blood is 7.35 – 7.45.
The bicarbonate/carbonic acid system is an important buffer system in the blood.
H2O
CO H2O  H2CO  H3O HCO3-
Excess H3O+ entering the body fluids reacts with the HCO3- and excess OH- reacts with carbonic acid.

84. CO2 + H2O  H2CO3  H3O+ + HCO3-
CO2   H3O+   pH……………………. Acidosis
…….emphysema, difficulty with breathing, medulla affected by depressive drugs or accident trauma.
CO2   H3O+   pH……………………. Alkalosis
…….hyperventilation causes expiration of a lot of carbon dioxide eg. excitement, trauma, high temperatures