Science, Matter, and Energy Chapter 2

Question of the Day Easter Island and the civilization that once thrived and then largely disappeared is an example of what? Easter Island and the civilization that once thrived and then largely disappeared is an example of what?

An Environmental Lesson from Easter Island Fig. 2-1, p. 19

Science vs. Junk Science Scientific method Scientific method Frontier science Frontier science Sound science (consensus science) Sound science (consensus science) Junk science Junk science

Matter and its Types What is matter? - anything that has mass and takes up What is matter? - anything that has mass and takes up space space Elements - the building blocks of matter Elements - the building blocks of matter Compounds - two or more elements held together by Compounds - two or more elements held together by chemical bonds chemical bonds Chemical bonds - Ionic, covalent, hydrogen Chemical bonds - Ionic, covalent, hydrogen Atoms and ions - the smallest unit of matter that has the Atoms and ions - the smallest unit of matter that has the characteristics of a particular element characteristics of a particular element Chemical formulas Chemical formulas Organic and inorganic compounds Organic and inorganic compounds

Fig. 2-3, p.23 Natural Capital

Organic Compounds Hydrocarbons Hydrocarbons Chlorinated hydrocarbons Chlorinated hydrocarbons Simple carbohydrates (simple sugars) Simple carbohydrates (simple sugars) Polymers and monomers Polymers and monomers Complex carbohydrates Complex carbohydrates Proteins Proteins Nucleic acids (DNA and RNA) Nucleic acids (DNA and RNA)

Atoms Subatomic particles Subatomic particles ProtonsProtons NeutronsNeutrons ElectronsElectrons Atomic number - # of protons in the nucleus Atomic number - # of protons in the nucleus Mass number - sum of the # of protons and Mass number - sum of the # of protons and neutrons in nucleus of an atom neutrons in nucleus of an atom Isotopes Isotopes

Matter Quality High-quality matter High-quality matter Low-quality matter Low-quality matter Material efficiency (resource productivity) Material efficiency (resource productivity)

Changes in Matter Physical Physical Chemical Chemical In text on page 26 Chemical Reaction of Burning Carbon

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

Matter and Pollution Chemical nature of pollutants Chemical nature of pollutants Concentration Concentration Persistence: how long pollutants stay in the Persistence: how long pollutants stay in the air,water,soil, or body. air,water,soil, or body. Degradable (nonpersistent) pollutantsDegradable (nonpersistent) pollutants Biodegradable pollutantsBiodegradable pollutants Slowly degradable (persistent) pollutantsSlowly degradable (persistent) pollutants Nondegradable pollutants (Pb, Hg, As)Nondegradable pollutants (Pb, Hg, As)

Matter and Pollution  Point Source Pollution Single Identifiable sources Smokestacks, sewer or drain outlets into lakes or streamsSmokestacks, sewer or drain outlets into lakes or streams Easiest to identify and controlEasiest to identify and control  Nonpoint Source Pollution Dispersed and difficult to identify Pesticides sprayed into air, runoff of fertilizer from fields into lakes and streams Pesticides sprayed into air, runoff of fertilizer from fields into lakes and streams Hardest to identify and control Hardest to identify and control

Nuclear Change Natural radioactive decay Natural radioactive decay Fission Fission Fusion Fusion

Nuclear Fission Critical Mass - produces chain reaction - release of energy for power plant Critical Mass - produces chain reaction - release of energy for power plant Thermal pollution released into environment under normal conditions. Thermal pollution released into environment under normal conditions. Creates high level radioactive waste. Creates high level radioactive waste.

Nuclear Fusion Uncontrolled - weapons Uncontrolled - weapons Controlled - possible future energy source but not possible at this time Controlled - possible future energy source but not possible at this time

Sun High energy, short wavelength Wavelength in meters (not to scale) Low energy, long wavelength Ionizing radiationNonionizing radiation Cosmic rays Gamma rays X rays Near ultraviolet waves Far ultraviolet waves Near infrared waves Far infrared waves microwaves TV waves Radio waves visible waves Fig. 2-8, p. 29 Electromagnetic Spectrum

Fig. 2-9, p. 30 Ultraviolet Visible Infrared Sunlight Wavelength (micrometers) Energy emitted from sun (kcal/cm 2 /min)

Very high High Moderate Low Electricity Very high temperature heat (greater than 2,500°C) Nuclear fission (uranium) Nuclear fusion (deuterium) Concentrated sunlight High-velocity wind High-temperature heat (1,000–2,500°C) Hydrogen gas Natural gas Gasoline Coal Food Normal sunlight Moderate-velocity wind High-velocity water flow Concentrated geothermal energy Moderate-temperature heat (100–1,000°C) Wood and crop wastes Dispersed geothermal energy Low-temperature heat (100°C or lower) Very high-temperature heat (greater than 2,500°C) for industrial processes and producing electricity to run electrical devices (lights, motors) Mechanical motion (to move vehicles and other things) High-temperature heat (1,000–2,500°C) for industrial processes and producing electricity Moderate-temperature heat (100–1,000°C) for industrial processes, cooking, producing steam, electricity, and hot water Low-temperature heat (100°C or less) for space heating Relative Energy Quality (usefulness) Source of EnergyEnergy Tasks Fig. 2-10, p. 31 Energy Quality

First Law of Thermodynamics Energy is not created or destroyed Energy is not created or destroyed Energy only changes form Energy only changes form Can’t get something for nothing Can’t get something for nothing Energy input = Energy output Energy input = Energy output

Second Law of Thermodynamics In every transformation, some energy quality is lost In every transformation, some energy quality is lost You can’t break even in terms of energy quality You can’t break even in terms of energy quality Second Law greatly affects life Second Law greatly affects life

Examples of the Second Law Cars: only 20-25% of the energy from burning gasoline produces mechanical energy Cars: only 20-25% of the energy from burning gasoline produces mechanical energy Ordinary light bulb: 5% energy is useful light, rest is low-quality heat Ordinary light bulb: 5% energy is useful light, rest is low-quality heat Living systems: quality energy lost with every conversion Living systems: quality energy lost with every conversion

Solar energy Chemical energy (photosynthesis) Chemical energy (food) Mechanical energy (moving, thinking, living) Waste heat Waste heat Waste heat Waste heat Fig. 2-11, p. 32 Second Law of Thermodynamics

Matter and Energy Change: Laws and Sustainability Unsustainable high-throughput (high-waste) economies - Bad Unsustainable high-throughput (high-waste) economies - Bad Matter-recycling-and-reuse economy - Good Matter-recycling-and-reuse economy - Good Sustainable low-throughput (low-waste) economies - Best Sustainable low-throughput (low-waste) economies - Best