2. Science, and Critical Thinking Science is an attempt to discover order in nature and use that knowledge to make predictions about what is likely to happen in nature. Goal Goal of science is a new idea, principle, or model that: 1. Connects and explains certain scientific data 2. Leads to useful predictions about what is likely to happen in nature

3. What Scientists Do  Ask questions or identify a problem to be investigated Ask a question Do experiments and collect data Fig. 3-2 p. 41  Collect data by making observations or measurements (Confirmed by different investigators)

4.  Scientific (natural) laws - result of lots and lots of data collection. What we see happening over and over in nature, with the same results  Scientific hypotheses - best guess of what is happening given available data, then retest. Ask a question Do experiments and collect data Formulate hypothesis to explain data Interpret data Well-tested and accepted patterns In data become scientific laws What Scientists Do Do more Experiments to test hypothesis

5.  Scientific theories - verified, highly reliable, and widely accepted scientific hypothesis (or explanations of data and laws) Ask a question Do experiments and collect data Formulate hypothesis to explain data Do more Experiments to test hypothesis Revise hypothesis if necessary Well-tested and accepted hypotheses become scientific theories Interpret data Well-tested and accepted patterns In data become scientific laws What Scientists Do Closest thing to “truth” that science can provideClosest thing to “truth” that science can provide

6.  Consensus science  Frontier science Scientific “breakthroughs” that have not yet been widely tested, therefore: “Healthy” disagreement exists among scientists about validity of various hypothesis and accuracy of data. Data, theories, and laws are widely accepted by those considered experts in the field

7. Science can: 1. Disprove things 2. Establish that a particular model, theory, or law has a very high probability of being true. Science cannot: - Prove that their theories, models, and laws are absolutely true.

8. Scientists and EVERYONE else needs to Critical Thinking and Environmental Studies Pg. 42 - 43

9. Models and Behavior of Systems  Inputs  Flows  Stores (storage areas)  Outputs Components that function and interact in some regular and theoretically predictable manner Can be isolated for study and observation - matter, energy, or information -Transport of inputs through the system at certain rates - Places in the system where inputs accumulate for a time before being released - Matter, energy, or info that flows out of a system, into sinks in the environment

10. System Regulation  Positive Feedback  Negative Feedback - Causes change in the same direction -Results in a lessening of the original change

11. System Regulation  Homeostasis  Time Delay  Synergy - Delay between stimulus and response - Problem builds up slowly until it reaches a threshold level and causes a fundamental shift in system (pop. growth, leaks in toxic waste dumps) - The combined effect is greater than the sum of the separate effects - Constant condition within a system

12. Law of Conservation of Problems The technological solution of one problem usually creates one or more new unanticipated problems. Because of the interconnectedness of nature’s systems we can rarely do one thing to a complex system without causing multiple and unpredictable effects.

13. Matter: Forms, Structure, and Quality  Elements  Compounds  Mixtures  Molecules

14. Atoms Subatomic Particles  Protons  Neutrons  Electrons Atomic Characteristics  Atomic number  Ions  Atomic mass  Isotopes = Number of Protons = Number of Protons and Neutrons - Atoms that have gained or lost one or more electrons - Various forms of the same element with different Atomic Masses

15. Examples of Atoms Fig. 3-4 p. 48

16. Chemical Bonds  Chemical formulas  Ionic bonds  Covalent bonds  Hydrogen bonds - Number of atoms of each type in a compound - Forces of attraction between oppositely charged ions - Bond formed by sharing of electrons Weaker bonds between molecules - slightly positive hydrogens of one molecule being attracted to slightly negative elements in other molecules

17. Organic Compounds  Organic vs. inorganic compounds  Hydrocarbons Carbon vs. no carbon Simplest organic molecule – Carbon and Hydrogen Methane, Propane, Butane

18.  Chlorinated hydrocarbons (CHC) DDT, polychlorinated biphenyls (PCB), and dioxins persistent in the environment and most bioaccumulate in the food chain. associated with suppression of the immune system and cancer.

19.  Chlorofluorocarbons  Simple carbohydrates  Complex carbohydrates  Proteins Composed of carbon, fluorine, chlorine and hydrogen Aerosol-spray propellants, refrigerants, solvents, and foam-blowing agents  Lipids

20. Genetic Material  Nucleic acids  Genes  Gene mutations  Chromosomes Fig. 3-6 p. 50

21. The Four States of Matter  Solid  Liquid  Gas  Plasma Fig. 3-7 p. 50

22. Matter Quality and Material Efficiency Fig. 3-8 p. 51  High-quality matter  Low-quality matter  Material efficiency (resource productivity) Concentrated, great potential Dilute, dispersed, low potential Total amount of material needed to produce each unit of goods (Currently 2-6%)

23. Energy: Forms  Kinetic energy  Potential energy Fig. 3-9 p. 52  Heat

24. Energy: Quality Fig. 3-12 p. 53  High-quality energy  Low-quality energy

25. The Law of Conservation of Matter  Matter is not consumed  Matter only changes form  There is no “away” - Nothing is consumed or thrown away

26. Nuclear Changes  Natural radioactive decay  Gamma rays  Alpha particles  Beta particles  Half life ( See Table 3-2 p. 56) Fig. 3-13 p. 56 Radioisotopes emit particles and / or radiation at a fixed rate until they are stable

27. Nuclear Reactions FissionFission Fig. 3-16 p. 57 FusionFusion Fig. 3-17 p. 58

28. Laws Governing Energy Changes  Energy is neither created nor destroyed  Energy only changes form  You can’t get something for nothing First Law of Thermodynamics (Energy) ENERGY IN = ENERGY OUT

29. Laws Governing Energy Changes Second Law of Thermodynamics  In every transformation, some energy is converted to heat  You cannot break even in terms of energy quality

30. Connections: Matter and Energy Laws and Environmental Problems  High-throughput (waste) economy Fig. 3-20 p. 60; see Fig. 3-21 p. 61  Matter-recycling economy

31.  Low-throughput economy