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Science, Systems, Matter, and Energy

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... Environmental Lesson from Easter Island Thriving society 15,000 people by 1400. Used resources faster than could be renewed By 1600 only a few trees remained. – PowerPoint PPT presentation

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Title: Science, Systems, Matter, and Energy


1
Chapter 2
  • Science, Systems, Matter, and Energy

2
Core Case Study Environmental Lesson from
Easter Island
  • Thriving society
  • 15,000 people by 1400.
  • Used resources faster than could be renewed
  • By 1600 only a few trees remained.
  • Civilization collapsed
  • By 1722 only several hundred people left.

Figure 2-1
3
Feedback Loops How Systems Respond to Change
  • Outputs of matter, energy, or information fed
    back into a system can cause the system to do
    more or less of what it was doing.
  • Positive feedback loop causes a system to change
    further in the same direction (e.g. erosion)
  • Negative (corrective) feedback loop causes a
    system to change in the opposite direction (e.g.
    seeking shade from sun to reduce stress).

4
Feedback Loops
  • Negative feedback can take so long that a system
    reaches a threshold and changes.
  • Prolonged delays may prevent a negative feedback
    loop from occurring.
  • Processes and feedbacks in a system can
    (synergistically) interact to amplify the
    results.
  • E.g. smoking exacerbates the effect of asbestos
    exposure on lung cancer.

5
Organic Compounds Carbon Rules
  • Organic compounds contain carbon atoms combined
    with one another and with various other atoms
    such as H, N, or Cl-.
  • Contain at least two carbon atoms combined with
    each other and with atoms.
  • Methane (CH4) is the only exception.
  • All other compounds are inorganic.

6
Organic Compounds Carbon Rules
  • Hydrocarbons compounds of carbon and hydrogen
    atoms (e.g. methane (CH4)).
  • Chlorinated hydrocarbons compounds of carbon,
    hydrogen, and chlorine atoms (e.g. DDT
    (C14H9Cl5)).
  • Simple carbohydrates certain types of compounds
    of carbon, hydrogen, and oxygen (e.g. glucose
    (C6H12O6)).

7
States of Matter
  • The atoms, ions, and molecules that make up
    matter are found in three physical states
  • solid, liquid, gaseous.
  • A fourth state, plasma, is a high energy mixture
    of positively charged ions and negatively charged
    electrons.
  • The sun and stars consist mostly of plasma.
  • Scientists have made artificial plasma (used in
    TV screens, gas discharge lasers, florescent
    light).

8
Matter Quality
  • Matter can be classified as having high or low
    quality depending on how useful it is to us as a
    resource.
  • High quality matter is concentrated and easily
    extracted.
  • low quality matter is more widely dispersed and
    more difficult to extract.

Figure 2-8
9
CHANGES IN MATTER
  • Matter can change from one physical form to
    another or change its chemical composition.
  • When a physical or chemical change occurs, no
    atoms are created or destroyed.
  • Law of conservation of matter.
  • Physical change maintains original chemical
    composition.
  • Chemical change involves a chemical reaction
    which changes the arrangement of the elements or
    compounds involved.
  • Chemical equations are used to represent the
    reaction.

10
Chemical Change
  • Energy is given off during the reaction as a
    product.

11
Types of Pollutants
  • Factors that determine the severity of a
    pollutants effects chemical nature,
    concentration, and persistence.
  • Pollutants are classified based on their
    persistence
  • Degradable pollutants
  • Biodegradable pollutants
  • Slowly degradable pollutants
  • Nondegradable pollutants

12
Nuclear Changes Radioactive Decay
  • Natural radioactive decay unstable isotopes
    spontaneously emit fast moving chunks of matter
    (alpha or beta particles), high-energy radiation
    (gamma rays), or both at a fixed rate.
  • Radiation is commonly used in energy production
    and medical applications.
  • The rate of decay is expressed as a half-life
    (the time needed for one-half of the nuclei to
    decay to form a different isotope).

13
Nuclear Changes Fission
  • Nuclear fission nuclei of certain isotopes with
    large mass numbers are split apart into lighter
    nuclei when struck by neutrons.

Figure 2-9
14
Stepped Art
Fig. 2-6, p. 28
15
Nuclear Changes Fusion
  • Nuclear fusion two isotopes of light elements
    are forced together at extremely high
    temperatures until they fuse to form a heavier
    nucleus.

Figure 2-10
16
ENERGY
  • Energy is the ability to do work and transfer
    heat.
  • Kinetic energy energy in motion
  • heat, electromagnetic radiation
  • Potential energy stored for possible use
  • batteries, glucose molecules

17
Electromagnetic Spectrum
  • Many different forms of electromagnetic radiation
    exist, each having a different wavelength and
    energy content.

Figure 2-11
18
Electromagnetic Spectrum
  • Organisms vary in their ability to sense
    different parts of the spectrum.

Figure 2-12
19
Relative Energy Quality (usefulness)
Source of Energy
Energy Tasks
Electricity Very high temperature heat (greater
than 2,500C) Nuclear fission (uranium) Nuclear
fusion (deuterium) Concentrated
sunlight High-velocity wind
Very high-temperature heat (greater than 2,500C)
for industrial processes and producing
electricity to run electrical devices (lights,
motors)
High-temperature heat (1,0002,500C) Hydroge
n gas Natural gas Gasoline Coal Food
Mechanical motion to move vehicles and other
things) High-temperature heat (1,0002,500C)
for industrial processes and producing
electricity
Normal sunlight Moderate-velocity
wind High-velocity water flow Concentrated
geothermal energy Moderate-temperature
heat (1001,000C) Wood and crop wastes
Moderate-temperature heat (1001,000C) for
industrial processes, cooking, producing steam,
electricity, and hot water
Dispersed geothermal energy Low-temperature heat
(100C or lower)
Low-temperature heat (100C or less) for
space heating
Fig. 2-13, p. 44
20
ENERGY LAWS TWO RULES WE CANNOT BREAK
  • The first law of thermodynamics we cannot create
    or destroy energy.
  • We can change energy from one form to another.
  • The second law of thermodynamics energy quality
    always decreases.
  • When energy changes from one form to another, it
    is always degraded to a more dispersed form.
  • Energy efficiency is a measure of how much useful
    work is accomplished before it changes to its
    next form.

21
Mechanicalenergy(moving,thinking,living)
Chemical energy (photosynthesis)
Chemical energy (food)
Solar energy
Waste Heat
Waste Heat
Waste Heat
Waste Heat
Fig. 2-14, p. 45
22
SUSTAINABILITY AND MATTER AND ENERGY LAWS
  • Unsustainable High-Throughput Economies Working
    in Straight Lines
  • Converts resources to goods in a manner that
    promotes waste and pollution.

Figure 2-15
23
Sustainable Low-Throughput Economies Learning
from Nature
  • Matter-Recycling-and-Reuse Economies Working in
    Circles
  • Mimics nature by recycling and reusing, thus
    reducing pollutants and waste.
  • It is not sustainable for growing populations.

24
Inputs (from environment)
System Throughputs
Outputs (into environment)
Energy conservation
Low-quality Energy (heat)
Energy
Sustainable low-waste economy
Waste and pollution
Waste and pollution
Pollution control
Matter
Recycle and reuse
Matter Feedback
Energy Feedback
Fig. 2-16, p. 47
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