1. Properties of Water Chapter 2.2

2. Water makes up about 60% of the human body and almost ¾ of the Earth's surface. There would be no life on Earth without water.

3. Is polar because there is an uneven distribution of electrons between the oxygen and hydrogen atoms. Because of their partial positive and negative charges, polar molecules can attract each other. The Water Molecule

4. Cohesion – an attraction between molecules of the same substance (water droplets & spiders walking on a pond surface) Adhesion – attraction between molecules of different substances (water rising in a narrow tube, water going up flowers – capillary action) Cohesion & Adhesion

5. Mixture – material composed of 2 or more elements/compounds that are physically mixed but not chemically combined (salt & pepper) Solution – mixture where things are evenly distributed (Kool-aid) Solutions & Suspensions

6. Solute is the substance that is dissolved (Kool-aid powder mix) Solvent is the substance in which the solute dissolves (water)

7. Suspension – mixture of water and non- dissolved material (oil and water)

8. Water molecules can split apart to form ions: H 2 O H+ + OH- water hydrogen ion + hydroxide ion Acids, Bases, and pH

9. The pH scale indicates the concentration of H+ ions in a solution *pH of 7 is neutral (pure water) * pH below 7 are acidic (lemon juice) * pH above 7 are basic (toothpaste)

10. Acids – any compound that forms H+ ions in a solution. (value below 7). Hydrochloric acid (HCl) produced by the stomach helps you digest food Bases – compound that produces hydroxide (OH-) ions in a solution (value above 7) Oven cleaners are very basic