1. Basic Chemistry

2. Atom

3. Isotope Same element, Different # of Neutrons

4. Elements and Electrons

5. Electron Orbitals

6. Orbitals

8. Ionic Bonds Transfer of electrons

9. NaCl, table salt

10. Covalent Bonds Sharing of electrons

11. Covalent Bond

12. The Carbon Atom

13. Water Molecule

14. Water: The Medium of Life Every living organism is dependent upon water for existence Basic and complex molecules perform their functions only within an aqueous environment

15. No Water, No Life

16. Water Good

17. Amoeba need water

18. Lizard and Lichen too

19. What’s So Special About Water?

20. Properties of Water 1.Polarity 2.Hydrogen Bonding 3.Universal Solvent 4.Heat Capacity 5.Cohesion 6.pH 7.Ice

21. A Polar Molecule Though water has no net charge it does exhibit partial charge, due to Oxygen’s pull on the shared electrons

23. Hydrogen Bonding The attraction of oppositely charged poles of a molecule, in this case a water molecule

25. Hydrogen Bonding - not just water to water

26. Universal Solvent All polar or charged molecules dissolve readily in water This is because of hydrogen bonding In living organisms most organic molecules have some type of charge and so may mix with water

27. Hydration Shell

29. Water as a solvent

30. Heat Capacity Temperature is defined as the kinetic energy of molecules (how fast they are moving) Energy is required to break hydrogen bonds Water takes a long time to heat up or cool off Why is the weather more constant near bodies of water?

31. Cohesion

33. H + (a free proton) Water molecules occasionally break apart (~ 1 out of 550 million) Ionization:H 2 0 ---> OH - + H + Concentration of H + in solution is known as pH: pH = -log [H + ]

34. pH Scale Acidic: High concentration of H + Basic (alkaline): Low concentration of H +

36. Why does Ice float?

38. Ice vs. Water