1. Legislating Risk Risk based laws – FDA Balancing laws –Clean Air Act –Safe Drinking Water Act Technology based laws –Proposition 65 in California

2. Controversy Animal experiments –Ethical? –Depend on how done? Cold fusion Greenhouse effect Cholesterol

3. Chemical Lingo

4. Elements Fundamental types of matter –Cannot be separated anymore All other substances are composed of 2 or more elements Most of the substances you know are not elements –Common elements Gold (24K) Aluminum (foil) Carbon (charcoal, diamonds, pencil “lead”)

9. Metals Shiny: Reflect light Opaque: Light doesn’t pass through Malleable: Can be hammered into shape Ductile: Can be drawn into wire Conductive: Both heat and electricity Most elements are metals –All are solids except mercury (Hg)

10. Nonmetals Are not malleable, ductile, or good conductors Solids, liquids, and gases

11. Symbols Each element has its own symbol –One or two characters –First character always capitalized –Second character never capitalized CO not the same as Co See table inside back cover

13. Atoms Smallest particle of an element with properties of the element Limit of chemical subdivision John Dalton – Theory of atoms –All matter made of atoms – 115 types → elements –All atoms of same type are similar but different from other types

14. Atoms John Dalton – Theory of atoms (cont.) –Relative number and arrangement of atoms→identity –Chemical change: union, separation, or rearrangement of atoms –Atoms are indestructible during chemical changes Approx. 245,000,000 atoms/inch Have seen atoms with electron microscopes

19. Compound Chemical combination of two or more elements. –Can’t be physically separated Can be broken down into constituent elements using chemical means. Has a definite, constant, elemental composition Has one set of properties under a given set of conditions. Has different properties than those of it’s constituent elements

20. Mixtures Physical combination of two or more substances. Components can be separated using physical means. Variable compositions possible Variable properties as composition varies Heterogeneous and homogeneous

21. Homogeneous Mixtures Components are dispersed on a molecular scale Solutions Appear to be pure substances One set of properties for each mixture

22. Heterogeneous Mixtures Components are dispersed on a larger than molecular scale Do not appear to be pure substances –You can see phase boundaries Different properties for different parts of the mixture

25. Heterogeneous Mixtures Components are dispersed on a larger than molecular scale Do not appear to be pure substances –You can see phase boundaries Different properties for different parts of the mixture Sometimes may appear as a pure substance –Colloids

28. H2 – C1 2, 3, 5 - 7, 9, 10, 12, 35, 39 - 41, 43, 54