1. October 16, 2015
Journal: What is the difference between an ionic and covalent bond?

2. Solutions and pH Scale

3. Solutions
Mixtures in which one or more substances are uniformly distributed in another
Solute – substance being dissolved (ex. salt or sugar)
Solvent – substance in which the solute dissolves (ex. water)
Amount of solute dissolved = concentration

4. Suspensions Suspension – particles do not dissolve
“hang” or suspend in water due to movement of water molecules
Over time they settle out

5. Solution (small) Colloid (intermediate) Suspension (large)
Size of Particles
Solution (small) Colloid (intermediate) Suspension (large)

6. pH H2O will sometimes split to form H+ and OH-
In pure water, H+ = OH- , so water is neutral
pH scale is based on the number of H+ and OH- in solution

7. Acids and Bases An acid has more H+ while a base has more OH- Ex.
neutral acid

8. pH scale Ranges from 0 - 14 7 is neutral (water) pH < 7 = acid
pH > 7 = base
Based on a factor of 10

9. Acids Highly corrosive Burning Sour taste
Ex. HCl, acetic acid, citric acid

10. Bases Feel slippery Bitter taste Very few foods, some medicine
Ex. Oven cleaner, bleach

11. pH in an organism Most cells work best around pH 7
Too high or too low pH cause enzymes in the body to stop working
To prevent large pH swings, organisms use buffers