Science, Systems, Matter, and Energy G. Tyler Miller’s Living in the Environment 14th Edition Chapter 3

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

Science, and Critical Thinking 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 accepted patterns In data become scientific laws Scientific data Scientific hypotheses Scientific (natural) laws Scientific theories Consensus science Frontier science Fig. 3-2 p. 33

Models and Behavior of Systems Inputs Flows (throughputs) Stores (storage areas) Outputs

System Regulation Positive Feedback Negative Feedback Time Delay Synergy

Matter: Forms, Structure, and Quality Elements Compounds Atoms Ions Molecules

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

Examples of Isotopes Fig. 3-5 p. 40

pH Measures acidity or alkalinity of water samples Scale 0 – 14 Acids: 0 – 6.9 Neutral 7.0 Alkaline (Basic) 7.1 – 14

Chemical Bonds Chemical formulas Ionic bonds Covalent bonds

Organic Compounds Organic vs. inorganic compounds Hydrocarbons Chlorinated hydrocarbons Simple carbohydrates Complex carbohydrates Proteins Nucleic acids

Genetic Material Nucleic acids Chromosomes Genes Genomes Compare Fig. 3-7 p. 42

The Four States of Matter Solid Liquid Gas Plasma

Matter Quality and Material Efficiency High-quality matter Low-quality matter Material efficiency (resource productivity) Fig. 3-8 p. 43

Energy Definition: Capacity to do “work” and transfer heat Types: Kinetic Potential Radiation: Energy & Wavelength

Electromagnetic Spectrum Fig. 3-9 p. 44

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. As the water boils, heat from the hot stove burner and pan radiate into the surrounding air, even though air conducts very little heat. 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. Fig. 3-11 p. 45

Energy: Quality High-quality energy Low-quality energy Fig. 3-12 p.46

Changes in Matter Physical Chemical

Chemical Changes or Reactions Fig. In text p. 47

The Law of Conservation of Matter Matter is not destroyed Matter only changes form There is no “throw away”

Matter and Pollution Chemical nature of pollutants Concentration Persistence Degradable (nonpersistent) pollutants Biodegradable pollutants Slowly degradable (persistent) pollutants Nondegradable pollutants

Nuclear Changes Natural radioactive decay Radioactive isotopes (radioisotopes) Gamma rays Alpha particles Beta particles Half life (See Table 3-2 p. 49) Ionizing radiation

Half-life Fig. 3-13, p. 49

Nuclear Reactions Fission Fusion Fig. 3-15 p. 50 Fig. 3-16 p. 50

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

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

Connections: Matter and Energy Laws and Environmental Problems High-throughput (waste) economy Matter-recycling economy Low-throughput economy

Environmental Solutions: Low-Throughput Economy Learning from Nature Fig. 3-19 p. 53