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CHAPTER 2
SCIENCE,
SYSTEMS,
MATTER AND
ENERGY
EASTER ISLAND
CASE STUDY—EASTER ISLAND
Collapse due to obsession with stone gods
Unsustainable use of resources—forests of
giant palms (shelter, tools, canoes to fish)
and basswoods (hauhau) for burning to cook
and keep warm, fibers to make ropes
https://www.youtube.com/watch?v=5DBTtC
4J0OY
EASTER ISLAND—TRAGEDY OF THE
COMMONS
 NO TREES
1. Could not build canoes, leave island
2. Springs dry up because of no
absorption of water and slow water
release
3. Soil erosion, crops failed causing
famine
4. No wood for cooking, warmth
5. Devoured all seabirds and landbirds
SCIENTIFIC METHOD
 Skepticism, peer review, reproducibility
 Hypothesis—testable, proposed solution
 Experiment
1. Control—standard to compare
2. Constants—factors that remain the same
3. Manipulated variable—factor being
tested
4 Responding variable—results
READING QUIZ—PP. 34-47
Atoms—basic building block of matter that
retains properties of the substances
1. Protons—positive particles in nucleus
that identifies element (atomic number)
2. Neutrons—neutral particle in nucleus
that together with protons make atomic
mass number
http://41.media.tumblr.com/37ebe403689414269ccad2b5675e334d/tumblr_m
mix7dm0b21res364o1_1280.jpg
MATTER
Elements—only one kind of atom
represented by symbol
96.3% of body weight is CHNO
Molecules—2 or more atoms chemically
combined
Compound—2 or more DIFFERENT atoms
chemically combined represented by formula
http://3.bp.blogspot.com/_8RHzyAodrNI/TKggoNTmxEI/AAAAAAAAAC
g/FEtGkaBzSD4/s1600/elementsAndCompounds.gif
FORMULAS TO KNOW
NaCl, H2O, O2, O3, N2, N2O (nitrous
oxide), NO (nitric oxide), H2S, CO, CO2,
NO2 (nitrous dioxide), SO2, NH3, H2SO4,
HNO3 (nitric acid), CH4, C6H12O6
DIFFERENT FORMS OF ATOMS
Isotopes—different number of neutrons but
same number of protons
Ions—atom that has lost/gained electrons
Positive—lost electrons
Negative—gained electrons
http://iqa.evergreenps.org/science/phy_science/isotopes_files/nn3.gif
http://gcserevision101.files.wordpress.com/2009/02/halogenionic-bond.jpg
ORGANIC MOLECULES
Contain at least 2 carbons bonded together
with H, O, N, S
Most chemicals making up body, vitamins,
plastics, aspirin, penicillin
CH4—Methane is exception of organic
molecule with only 1 carbon
Hydrocarbons—C to H
ORGANIC MOLECULES
Chlorinated hydrocarbons—DDT insecticide,
C14H9Cl5
Simple carbohydrates—glucose, fructose,
galactose C6H12O6
http://www.nutrientsreview.com/wp-content/uploads/2014/09/Glucoseformula.jpg
http://www.davistownmuseum.org/cbm/chemicals/ddt.
jpg
CELLS
Prokaryotes
No nucleus, no membrane-bound organelles,
contains ribosomes, single strand of circular
DNA, single cell bacteria, simple, small
 Eukaryotes—Nucleus, many double
membrane-bound organelles, large DNA in
nucleus, more complex, larger
http://img.youtube.com/vi/9o6huiw7u5o/0.jpg
MACROMOLECULES
Polymers made of monomers linked together
Complex carbohydrates
Cellulose—plant cell wall structure
Starch—plant energy storage
Chitin—animal structure of exoskeleton
Glycogen—animal energy storage in liver
and muscle
http://thumbs.dreamstime.com/z/cicada-shell-white3336393.jpg
http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.Fre
eContent.ImageService.svc/ImageService/Articleimage/2012/PY/c1
py00445j/c1py00445j-f1.gif
MACROMOLECULES
Proteins—made of amino acids
Nucleic acids—made of nucleotides
DNA  chromosomes genes
RNA carries DNA code to ribosome to
create protein
 Lipids—no monomer; long term energy
storage and composition of cell membranes
STATES AND CHANGES IN MATTER
States—solid, liquid, gas, plasma
Artificial plasma—pass electricity through
gas to make fluorescent light, neon signs,
TV/computer screens
 Matter Quality—how useful a form of
matter is based on availability and
concentration
http://www.assignmenthelp.net/assignment_help/images/chemistry/states-of-matter/stateof-matter-assignment-help.PNG
MATTER QUALITY
High-quality matter—concentrated, near
earth’s surface; great potential as resource
(aluminum cans)
 Low-quality matter—dilute, deep
underground or dispersed in ocean,
atmosphere; little potential as resource
(aluminum ore)
CONSERVATION OF MATTER
Chemical changes create energy and waste
Pollutants—Severity of harmful effects
1. Concentration—substance per given
volume
2. Persistence—how long pollutant stays in
air, water, soil, body
PERSISTENCE
 Degradable—broken down completely or
reduced to acceptable levels by natural
processes
 Biodegradable—broken down by living things
(bacteria)—sewage plants
 Slow to degrade—takes decades or longer such
as DDT/most plastics
 Nondegradable—is not broken down by natural
processes (lead, mercury, arsenic)
http://i00.i.aliimg.com/photo/v0/50006811122_4/Bioclean_co
mpost_for_biodegradable_waste_products_from.jpg
http://vietnamnews.vn/ImageHand
ler.ashx?ThumbnailID=125080
http://www.mhhe.com/biosci/genbio/enger/student/olc/art_quizze
s/genbiomedia/0414.jpg
NUCLEAR CHANGES
Radioactive decay—emission of alpha/beta
particles, gamma rays, or both at fixed rate
Half-life—characteristic rate of decay
different isotopes
time needed for one half of nuclei in given
quantity of isotope to decay and emit
radiation
NUCLEAR CHANGES
Half-life estimates how long radioisotopes
sample must be safely stored
Approx. 10 half-lives
I-131 (concentrates in thyroid) has half-life
of 8 days (protection needed for 80 days)
Plutonium-239 (lung cancer) in nuclear
reactors has half-life of 24,000 years
(10 X 24,000) = 240,000 years
ENERGY—CASE STUDY
Ability to do work
Today—person uses 2,000 kcal/day for
basic needs plus 600,000 kcal/day used by
machines and systems for lifestyle
History
Fire (hunters/gathers) cooked, light heat
Farmers—animal power for plowing,
transport, carrying loads
ENERGY—CASE STUDY
Wind— Pump water, transport, flowing
water to transport goods/people, mills for
grinding grains, produce electricity
Steam engine—firewood 91% of energy
used until depletion of forests 1850
Coal—factories, heating
1800—18% wood, 73% coal
ENERGY—CASE STUDY
1900 40% oil, 38% coal, 18% natural gas
1950 Nuclear
Today—82% nonrenewable resources
33% oil, coal 22%, natural gas 21%
6% nuclear,
11% wood/biomass
7% flowing water, geothermal,
sun, wind
http://wesrch1.wesrch.com/User_images/wiki/2fb8b474ae494b70b2b
bca47c7db2048_1236984472.jpg
ENERGY LAWS
First Law of Thermodynamics
Energy cannot be created or destroyed
 Also known as Law of Conservation of
Energy
 Second Law of Thermodynamics
Energy quality always decreases with every
energy change to decrease useful energy
EXAMPLES OF SECOND LAW
Driving vehicles—approx. 6% high-quality
gas energy actually moves car; 94%
degraded and lost as heat
Electrical energy—light bulbs 5% useful
energy; 95% low-quality heat loss
Solarchemical of
photosynthesischemical in
foodsmechanical for moving (each change
loses heat energy
ENERGY CANNOT BE RECYCLED
Energy efficiency (productivity)—measure
of how much useful work is accomplished by
input of energy
Approx. 16% of used energy in U.S. ends in
useful work
Approx. 84% wasted unavoidably with 41%
due to Second Law and unnecessarily wasted
with 43%
SUSTAINABILITY
Cheapest, quickest solution to get more
energy is to STOP wasting with gasefficient vehicles, well-insulated houses,
energy efficient lights, heat/cool,
appliances
Ideally, use of solar, hydropower, wind,
geothermal biofuels
SUSTAINABILITY?
Most nations increase economic growth by
creating goods/services
 Adds large amounts of waste, pollution, lowquality heat
 Pooling of pollutants in sinks (soil, water,
body, air) which increases harmful levels
 UNSUSTAINABILIY