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Science, Systems, Matter, and Energy

Science, Systems, Matter, and Energy. G. Tyler Miller’s Living in the Environment 13 th Edition Chapter 3. Dr. Richard Clements Chattanooga State Technical Community College Charlotte Kirkpatrick. Key Concepts. Science as a process for understanding. Components and regulation of systems.

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Science, Systems, Matter, and Energy

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  1. Science, Systems, Matter, and Energy G. Tyler Miller’s Living in the Environment 13th Edition Chapter 3 Dr. Richard Clements Chattanooga State Technical Community College Charlotte Kirkpatrick

  2. Key Concepts • Science as a process for understanding • Components and regulation of systems • Matter: forms, quality, and how it changes; laws of matter • Energy: forms, quality, and how it changes; laws of energy • Nuclear changes and radioactivity

  3. Science, and Critical Thinking • Scientific data: facts, observations and measurements • Scientific hypotheses: tentative explanation that explains scientific data and makes predictions; testable • Scientific (natural) laws: description of what we see happening over and over again in nature. Highly reliable • Scientific theories:widely accepted explanations of data and laws; high degree of certainty, supported by extensive evidence • Consensus science vs. Frontier science Fig. 3-2 p. 41

  4. Science, and Critical Thinking: Consensus vs. Frontier Science • Frontier science: Preliminary results; untested, scientific “breakthroughs” Reputable scientists question and disagree about the meaning and accuracy as well as the validity of the hypothesis • Consensus science: data, theories , and laws; widely accepted

  5. Science, and Critical Thinking: Inductive vs. Deductive Reasoning • Inductive Reasoning: Using specific observations and measurements to arrive at a general conclusion or hypothesis “Bottom-up” reasoning: specific to general Very high probability or degree of certainty that it is true • Deductive Reasoning:Using logic to arrive at a specific conclusion based on a generalization or premise “Top-down” reasoning: general to specific Conclusions are valid if the premise is correct and we do not use faulty logic to arrive at the conclusion Intuition, imagination, and creativity are also important to sciencediscovery.

  6. What Scientists Do. Ask a question Do experiments and collect data Interpret data Well-tested and accepted patterns In data become scientific laws Formulate hypothesis to explain data Do more Experiments to test hypothesis Revise hypothesis if necessary Well-tested and accepted hypotheses become scientific theories Fig. 3-2 p. 41

  7. Systems: A set of components that 1. function and interact in some regular and theoretically predictable manner and 2. be isolated for the purposes of observation and study The environment has many interacting systems involving living and nonliving things

  8. Models and Behavior of Systems • Inputs: such as matter, energy or informationinto a system • Flows (throughputs):of matter, energy, or information within a system at certain rates. • Stores (storage areas):within a system where matter,energy, or information can accumulate for various lengths of time before being released. • Outputs:matter,energy or information that flows out of the system into sinks in the environment.

  9. Why use Models? Find out how systems work Evaluate which ideas or hypotheses work Some of the most powerful models are mathematical models. Models are only as good as the assumptions built into them and The data fed into them to make projections about the behavior of a complex system.

  10. System Regulation/ Feedback Loops • Feedback Loops: Occurs when an output of matter, energy, or information is fed back into the system as an input that changes the system • Positive Feedback: Change in a certain direction that causes further change in the same direction • Negative Feedback: One change leads to a lessening of that change Most systems contain one or a series of coupled positive and negative feedback loops

  11. System Regulation • Time Delay: Delay between input of a stimulus and the response to it. Time delays allow a problem to build up slowly until it reaches a threshold level and causes a fundamental shift in the behavior of a system. ex. Pop. Growth, leaks from toxic waste dumps, etc. • Synergy: when two or processes interact so the combined effect is greater than the sum of their separate effects.

  12. Systems/ Coupled Feedback Loops: Homeostasis Homeostasis: Maintenance of internal conditions in a system despite fluctuations in the internal environment Fig. 3-3 p. 46

  13. Law of Conservation of Problems The technological solution of one problem usually creates one or more new unanticipated problems

  14. Anticipating Environmental Surprises We can never do one thing: any action in a complex system has multiple and often unpredictable effects. Results from: Discontinuities due to a breaching of an environmental threshold Synergistic interactions Unpredictable, chaotic events

  15. Solar Water Heater Project Purpose: In a group of no more than 3 you will design, build and test a passive solar water heater. Design: this is your hypothesis, so it must be researched and based on known information or evidence from other research. You must include a written description of the process you went through to come up with the hypothesis, including your research information. Include a diagram of your design and a list of materials Procedure: Identify the procedures you went through to build the project (pictures must be included that show the group working together in the process). In addition, include a journal of the steps as well.

  16. Solar Water Heater Project Testing: Identify your controlled, manipulated and responding variables then perform at least 3 tests of your design. One test may be the final one done at school. Alterations may be performed to modify your design (hypothesis), but they must be documented. Data: keep a data table for a control and your experimental design. Be sure to include data at multiple intervals, not just beginning temp and ending temp. Analysis: Look at your data and rework the data into a graph or some other way to analyze the data other than a chart of numbers. Determine what the data tells you. Conclusion: is your design/hypothesis efficient at heating water and if it is not why and what would you do to improve it. Were there any experimental errors you could identify?

  17. Solar Water Heater Project Reporting: You may turn in only one report but each person in the group must have contributed equally in all aspects of the project. In other words; you can not have one person design it, another person build it and another person write up the report; you must all be involved at all steps in the process. We will have the final testing day as close to two weeks from Friday as possible, all depending on weather, so keep track of the weather report. I will give you at least a day notice as to when you need to bring in your project for the final testing.

  18. Matter: Forms, Structure, and Quality • Elements • Compounds • Molecules • Mixtures

  19. Atoms Subatomic Particles • Protons • Neutrons • Electrons Atomic Characteristics • Atomic number • Ions • Atomic mass • Isotopes

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

  21. Chemical Bonds • Chemical formulas • Ionic bonds: transfer of electrons • Covalent bonds: share electrons, with in a molecule • Hydrogen bonds: bonds between molecules

  22. Organic Compounds Carbon containing compounds Carbon in bonds with itself and one or more other elements like; H, O, N, S, P, Cl, and Fl May be natural or synthetic Do not have C-C or C-H bonds Ex. NaCl, H2O, N2O, NO, CO, CO2 , NO2, SO2, NH3, H2S, H2SO4, HNO3 Organic vs. inorganic compounds

  23. Organic Compounds • Hydrocarbons:compounds of carbon and hydrogen atoms. Ex. Methane CH4 • Chlorinated hydrocarbons: compounds of chlorine, carbon and hydrogen atoms. Ex. DDT and PCB’s • Chlorofluorocarbons (CFC’s): compounds of carbon, chlorine and fluorine atoms. Ex. Freon-12

  24. Organic Compounds/ Polymers and Monomers • Simple carbohydrates: Monomers,compounds of carbon and hydrogen and oxygen. Ex. Glucose Building block for larger polymers of complex carbohydrates. Ex. Starch • Amino Acids: monomer composed of C, H, O, N for the larger polymer of Proteins • Nucleotides: monomers also composed of C, H, O, N for the larger polymers of Nucleic Acids (RNA and DNA)

  25. Genetic Material • Genes • Nucleic acids • Gene mutations • Chromosomes Fig. 3-6 p. 50

  26. The Four States of Matter The three physical states of Matter • Solid • Liquid • Gas Differ by spacing and orderliness of its atoms, ions, or molecules • Plasma: not a physical state of matter but composed of a high energy mixture of roughly equal numbers of positively charged ions and negatively charged electrons. Fig. 3-7 p. 50

  27. Matter Quality and Material Efficiency • High-quality matter: Concentrated, close to surface, useful • Low-quality matter: dilute,deep underground, not so useful • Entropy: A measure of the disorder or randomness in a closed system. • Material efficiency(resource productivity) Fig. 3-8 p. 51

  28. Energy: Forms • Kinetic energy • Potential energy • Heat Fig. 3-9 p. 52 Electromagnetic spectrum

  29. Transfer of Heat Energy Convection Conduction Radiation Heat from a stove burner causes atoms or molecules in the pan’s bottom to vibrate faster. The vibrating atoms or molecules then collide with nearby atoms or molecules, causing them to vibrate faster. Eventually, molecules or atoms in the pan’s handle are vibrating so fast it becomes too hot to touch. Heating water in the bottom of a pan causes some of the water to vaporize into bubbles. Because they are lighter than the surrounding water, they rise. Water then sinks from the top to replace the rising bubbles.This up and down movement (convection) eventually heats all of the water. As the water boils, heat from the hot stove burner and pan radiate into the surrounding air, even though air conducts very little heat. Heat: the total kinetic energy of all the moving atoms, ions, or molecules within a given substance. Fig. 3-11 p. 553

  30. Energy: Quality • High-quality energy: concentrated and performs useful work • Low-quality energy: dispersed and does little useful work Fig. 3-12 p. 53

  31. Physical and Chemical Changes Fig. In text p. 54

  32. The Law of Conservation of Matter • Matter is not consumed • Matter only changes form • There is no “away”

  33. Matter and Pollution • Chemical nature of pollutants: How active and harmful it is to living organisms • Concentration: the amount per unit volume of Air, water, soil, or body weight • Persistence: How long it stays in the air, water, soil or body

  34. Categories of Pollutants Based on Persistence • Degradable (nonpersistent) pollutants: broken down completely by natural physical, chemical, and biological processes • Biodegradable pollutants: degradable pollutants that are broken down by bacteria • Slowly degradable (persistent) pollutants: Take decades or longer to decay. Ex. DDT and most plastics • Nondegradable pollutants:cannot be broken down by natural processes. Ex. Lead mercury, arsenic

  35. Nuclear Changes • Radioactive isotopes (radioisotopes): unstable isotopes that emit high energy radiation or fast moving particles or both at a fixed rate. • Gamma rays: High energy EM radiation • Alpha particles: fast-moving positively charged matter consisting of two protons and two neutrons • Beta particles: high speed electrons

  36. Penetrating ability of the 3 types of ionizing radiation emitted by radioactive isotopes Fig. 3-13 p. 56

  37. Nuclear Changes • Half life (See Table 3-2 p. 56): amount of time it takes for one-half of the nuclei in a radioactive isotope to decay and emit their radiation to form a different isotope

  38. Nuclear Changes • Ionizing radiation: • How much?Not too much most of it is background and natural. Usually the excess comes from medical X-rays and diagnostic tests • Effects:genetic damage and somatic damage

  39. Nuclear Reactions Fission Fig. 3-16 p. 57 • Nuclei of certain isotopes with large mass numbers are split apart into lighter nuclei when struck by neutrons; each fission releases two or three neutrons and energy. • Each of these neutrons, in turn, can cause additional fission. • There must be a critical mass of the fissionable material for the multiple fissions to take place. This is known as a Chain Reaction.

  40. Ways of Using Nuclear Fission Atomic Bomb: Uncontrolled nuclear fission caused by the release of an enormous amount of energy. An explosive charge forces two fissionable masses together so that the critical mass may be reach and a chain reaction can take place. Nuclear Power Plant: Controlled nuclear fission so that the chain reaction only uses one of every two or three neutrons to split another nucleus. The splitting of a nuclei causes the release of heat to produce steam to power a turbine.

  41. Nuclear Reactions Fusion Fig. 3-17 p. 58 • Nuclear change in which to smaller nuclei (such as H) are forced together at extremely high temperatures until they form a heavier nucleus and excess energy is released. • Fusion of HHe is the source of energy in the sun. • Hydrogen weapons form D-T fusion reaction. • Attempts to have controlled Fusion for energy purposes are still in the experimental phase

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

  43. Laws Governing Energy Changes Second Law of Thermodynamics • In every transformation, some energy is converted to heat (lower quality) Always end up with less energy than we started with. Energy Efficiency will never be 100%. Cannot recycle or reuse • You cannot break even in terms of energy quality (always goes from more useful to less useful form)

  44. 2nd Law of Thermodynamics

  45. Connections: Matter and Energy Laws and Environmental Problems • High-throughput (waste) economy: advanced industrialized nations, increase economic growth through increase flow of matter and energy resources • Matter-recycling economy:allow economic growth without depleting matter resources or increases pollution • Low-throughputeconomy: Sustainability based on energy flow and matter recycling Fig. 3-20 p. 60; see Fig. 3-21 p. 61

  46. Low Throughput Economy

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