1. Properties of Water 2.2

2. Cohesion Attraction between molecules of the same substance.

3. Adhesion Attraction between molecules of different age groups of a population.

4. Mixture Material composed of two or more elements or compounds that are physically mixed together but not chemically combined.

5. Solution Mixture of two or more substances in which the molecules of the substances are evenly distributed.

6. Solute Substance that is dissolved in a solvent to make a solution.

7. Solvent Substance in which a solute is dissolved to form a solution.

8. Suspension Mixture of water and nondissolved materials.

9. pH Scale Measurement system used to indicate the concentration of hydrogen ions (H+) in solution; ranges from 0 to 14.

10. Acid Compound that forms hydrogen ions H+ in solution.

11. Base Compound that produces hydroxide ions OH+ in solution.

12. Buffer Weak acid or base that can react with strong acids or bases to help prevent sharp, sudden changes in pH.

13. Key Concept A water molecule is polar because there is an uneven distribution of electrons between the oxygen and hydrogen atoms.

14. Key Concept Acidic solutions contain higher concentrations of H+ ions than pure water and have pH values below 7.

15. Key Concept Basic, or alkaline, solutions contain lower concentrations of H+ ions than pure water and have pH values above 7.