Chemistry of Water https://www.youtube.com/watch?v=aVmU3CLxvgU

Structure 1 oxygen + 2 hydrogen Oxygen end is negatively charged Hydrogen ends are positively charged

Hydrogen Bonds Hydrogen Bonds: weak bonds that form between the O and H of different water molecules http://www.wiley.com/college/boyer/0470003790/reviews/pH/ph_water.htm

1. Polarity Polarity: water has an uneven distribution of charge Held together by covalent bonds Gives water special properties

Hydrophilic Hydrophilic: Water LOVING Will dissolve in water

Hydrophobic Hydrophobic: Water FEARING Will not dissolve in water

2. Universal Solvent Universal Solvent: Most solids and gases will dissolve in water because it is a polar molecule

3. Cohesion Cohesion: Water molecules are attracted to other water molecules

Results of COHESION Surface Tension: The surface of a liquid resisting an external force because of the hydrogen bonding of water molecules

4. Adhesion Adhesion: Water sticks to other molecules Water ADHERES to things

Results of ADHESION Capillary Action: Water “climbs” up the surface of other molecules

5. High Heat Capacity High Heat Capacity: water can hold its temperature Regulates temperature inside living cells Regulates temperature in the air and in the oceans

6. Density Density: because of the shape of water molecules, ice is less dense when it freezes Why would this be important to organisms that live in water?

7. pH pH scale: a measure of the acidity of a solution Water has a pH of 7 Most organisms need a pH between 5-7

Acids and Bases Ionization of water: as water molecules bump into each other, they lose or pick up a proton

Acids and Bases Hydroxide Ion: OH⁻ Hydronium Ion: H₃O⁺

Acids Acids: the number of hydronium (H₃O⁺) ions in a solution is greater than the number of hydroxide (OH⁻) ions H₂O  H⁺ + OH⁻ Hydrochloric Acid H⁺ + Cl⁻  HCl

Bases Bases: the number of hydroxide (OH⁻) ions in a solution is greater than the number of hydronium (H₃O⁺) ions H⁺ + H₂O  H₃O⁺ Sodium Hydroxide Na⁺ + OH⁻  NaOH

Solutions Solution: a mixture of one or more substances are equally distributed in another substance Solute: the substance dissolved that gets dissolved Solvent: the substance in which the solute is dissolved in