1. Basic Chemistry Biol 101

2. Outline Describe the basic structure of an atom Recognize the importance of electrons Understand isotopes and radioactivity Describe chemical bonds and why they form Be aware of the properties of water Understand pH and buffers

3. Matter, Molecules Elements & Atoms Matter Compounds … Molecules Elements … Atoms

4. Chemical Composition of the Human Body

5. Structure of an Atom - Subatomic Particles

6. Mass Number + + –– + – 2 2 2 Protons Neutrons Electrons Mass number = 4 + + 2e – Electron cloud Nucleus Helium atom

7. Mass Number + – 6 6 6 Protons Neutrons Electrons Mass number = 12 + + 6e – Nucleus Electron cloud Carbon atom

8. Atomic Number and Atomic Weight or Mass Number

9. Periodic Table of the Elements

10. Isotopes

11. Chart of Isotopes

12. Radioactivity Beta – neutron decay to loss of electron Alpha – loss of two neutrons and two protons Gamma – loss of energy

13. Energy from different sources SourceEnergy (MJ/kg) Firewood16 Coal9-30 Natural Gas39 Crude oil45 Uranium (nuclear fission)500,000

14. Radioactive Dating Radioisotope half life C-14 5730 years H-3 12.25 years U-2384.5 billion years

15. Summary of Isotopes 92 naturally occurring elements 270 stable isotopes 50 natural radioisotopes 1000s artificial isotopes Radioactivity is released by unstable isotopes Radioactivity –Always comes from the breakdown of a nucleus –Lot of energy –Uses: Energy, Dating Materials, Research & Medicine

16. Energy Levels (Electron Shells) Hydrogen (H) Atomic number = 1 Carbon (C) Atomic number = 6 Nitrogen (N) Atomic number = 7 Oxygen (O) Atomic number = 8 Outermost electron shell holds 8 electrons First electron shell holds 2 electrons Electron Nucleus

17. Energy Levels (Electron Shells) & Electron Arrangements

18. Energy Levels (Electron Shells)

19. Ionic Bond Formation

20. Sodium Chlorine Sodium Chloride Molecules Have Emergent Properties

21. Covalent Bonding

22. Covalent Bonds Molecular and Structural Formulas

23. Water Structure and Hydrogen Bonding

24. Hydrogen bond (+) H H (–) O

25. Fig. 2.15(TE Art) Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Properties of Water Cohesion Adhesion

26. Properties of Water High Surface Tension

27. Properties of Water Moderates Temperature High Heat Storage High Heat of Vaporization

28. Fig. 2.11b Properties of Water Ice Formation

29. Water molecules Salt crystal Na + Cl – Na + Cl – Fig. 2.17(TE Art) Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Properties of Water Solvent forms Hydration Shells

30. Properties of Water

31. H 2 O H + + OH - pH = hydrogen ion concentration Basic solution Oven cleaner Acidic solution Neutral solution pH scale 0 1 2 3 4 5 6 7 8 9 10 11 12 Lemon juice, gastric juice Grapefruit juice, soft drink Tomato juice Human urine Pure water Human blood Seawater Milk of magnesia Household ammonia Household bleach Increasingly ACIDIC (Higher concentration of H + ) NEUTRAL [H + ]=[OH – ] H+H+ H+H+ H+H+ OH – H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ H+H+ Increasingly BASIC (Lower concentration of H + ) OH – H+H+ 14 13

32. Buffers

33. END Basic Chemistry