Chapter 2Chapter 2

Science, Systems, Science, Systems, Matter, and EnergyMatter, and Energy

Core Case Study: Core Case Study: Environmental Lesson from Easter Environmental Lesson from Easter

IslandIsland Thriving societyThriving society

15,000 people by 1400.15,000 people by 1400. Used resources faster Used resources faster

than could be renewedthan could be renewed By 1600 only a few By 1600 only a few

trees remained.trees remained. Civilization collapsedCivilization collapsed

By 1722 only several By 1722 only several hundred people left.hundred people left.

Figure 2-1Figure 2-1

KEY TERMS - ECONOMYKEY TERMS - ECONOMY

Gross National ProductGross National Product Measures economic growth in a countryMeasures economic growth in a country Market value in current dollars of all goods and Market value in current dollars of all goods and

services produced services produced withinwithin and and outsideoutside of a country of a country by the country’s businesses during one yearby the country’s businesses during one year

Gross Domestic ProductGross Domestic Product Market value in current dollars of all goods and Market value in current dollars of all goods and

services produced services produced only withinonly within a country during a country during one yearone year

KEY TERMS - ECONOMYKEY TERMS - ECONOMY

Economic GrowthEconomic Growth Increase in the capacity to provide goods and Increase in the capacity to provide goods and

services for people’s useservices for people’s use Throughput of Matter and EnergyThroughput of Matter and Energy

Resources used to produce goods and services Resources used to produce goods and services through an economythrough an economy

High throughput means more consumption per High throughput means more consumption per personperson

KEY TERMS - ECONOMYKEY TERMS - ECONOMY

More Developed Countries (MDC)More Developed Countries (MDC) Highly industrialized Highly industrialized Average per capita GNP above $4000Average per capita GNP above $4000

Less Developed Countries (LDC)Less Developed Countries (LDC) Low to moderate industrialization Low to moderate industrialization Average per capita GNP below $4000 Average per capita GNP below $4000 (Africa, Latin America, and parts of Asia)(Africa, Latin America, and parts of Asia)

WEALTH GAPWEALTH GAP The gap between the per capita GNP of the The gap between the per capita GNP of the

rich, middle-income and poor has widenedrich, middle-income and poor has widened More than 1 billion people survive on less More than 1 billion people survive on less

than one dollar per daythan one dollar per day Situation has Situation has

worsened since worsened since 1980 1980

Environmental WorldviewsEnvironmental WorldviewsHow people think the world worksHow people think the world worksWhat they think their role in the world What they think their role in the world

should beshould beWhat they see as right and wrong What they see as right and wrong

environmental behavior (environmental environmental behavior (environmental ethics)ethics)

Planetary Management WorldviewPlanetary Management WorldviewIncreasingly common during Increasingly common during

the past 50 years.the past 50 years.We are the planet’s most We are the planet’s most

important speciesimportant speciesWe are in charge of the rest of We are in charge of the rest of

naturenature

Planetary Management WorldviewPlanetary Management WorldviewThere is always moreThere is always moreAll economic growth is goodAll economic growth is goodPotential for economic growth is Potential for economic growth is

limitlesslimitlessOur success depends on how well Our success depends on how well

we manage earth’s system we manage earth’s system for our for our benefitbenefit

Earth-Wisdom WorldviewEarth-Wisdom WorldviewNature exists for all of the earth’s species, Nature exists for all of the earth’s species,

not just for usnot just for usThere is not always moreThere is not always moreNot all forms of economic growth is Not all forms of economic growth is

beneficial to the environmentbeneficial to the environmentOur success depends on learning to Our success depends on learning to

cooperate with one another and with the cooperate with one another and with the earthearth

Working with the EarthWorking with the EarthEarth WisdomEarth Wisdom

Learning as much as we can about Learning as much as we can about how the earth sustains itself how the earth sustains itself

Adapt to ever-changing Adapt to ever-changing environmental conditions environmental conditions

Integrating such lessons from nature Integrating such lessons from nature into the ways we think and actinto the ways we think and act

ObservationsObservations Scientific data is collected by making Scientific data is collected by making

observations and taking measurementsobservations and taking measurements Observations involve the five senses, and Observations involve the five senses, and

help answer questions or problemshelp answer questions or problems QualitativeQualitative

of, relating to, or involving of, relating to, or involving qualityquality or kind or kind QuantitativeQuantitative

of, relating to, or involving the of, relating to, or involving the measurement of measurement of quantityquantity or amount or amount

QualitativeQualitative

RedRed Far from the earthFar from the earth

MicroscopicMicroscopic Burns quicklyBurns quickly

HotHot

QuantitativeQuantitative

700 nm wavelength700 nm wavelength 300 million light 300 million light

yearsyears Smaller than 1 umSmaller than 1 um Burns candle at 1 Burns candle at 1

cm per minutecm per minute 350 degrees C350 degrees C

Scientific MethodsScientific Methods There is no “one” scientific methodThere is no “one” scientific method

However, there are careful, systematic ways of thinking However, there are careful, systematic ways of thinking that scientists use to gather data and formulate and test that scientists use to gather data and formulate and test scientific hypothesesscientific hypotheses

One way of applying a scientific method…One way of applying a scientific method… ObservationObservation QuestionQuestion HypothesisHypothesis Test the hypothsisTest the hypothsis ExperimentExperiment ResultsResults ConclusionConclusion New hypothesis…repeatNew hypothesis…repeat

Scientific Reasoning and CreativityScientific Reasoning and Creativity

Inductive reasoningInductive reasoning Involves using specific observations and Involves using specific observations and

measurements to arrive at a general conclusion measurements to arrive at a general conclusion or hypothesis.or hypothesis.

Bottom-up reasoning going from specific to Bottom-up reasoning going from specific to general.general.

Deductive reasoningDeductive reasoning Uses logic to arrive at a specific conclusion.Uses logic to arrive at a specific conclusion. Top-down approach that goes from general to Top-down approach that goes from general to

specific.specific.

Frontier Science, Sound Science, and Frontier Science, Sound Science, and Junk ScienceJunk Science

Frontier science has not been widely tested Frontier science has not been widely tested (starting point of peer-review).(starting point of peer-review).

Sound science consists of data, theories and Sound science consists of data, theories and laws that are widely accepted by experts.laws that are widely accepted by experts.

Junk science is presented as sound science Junk science is presented as sound science without going through the rigors of peer-without going through the rigors of peer-review.review.

TYPES AND STRUCTURE OF TYPES AND STRUCTURE OF MATTERMATTER

Elements and CompoundsElements and Compounds Matter exists in chemical forms as elements and Matter exists in chemical forms as elements and

compounds.compounds.• Elements (represented on the periodic table) are the Elements (represented on the periodic table) are the

distinctive building blocks of matter.distinctive building blocks of matter.• Compounds: two or more different elements held Compounds: two or more different elements held

together in fixed proportions by chemical bonds.together in fixed proportions by chemical bonds.

IonsIons

An ion is an atom or group of atoms with one An ion is an atom or group of atoms with one or more net positive or negative electrical or more net positive or negative electrical charges.charges.

The number of positive or negative charges The number of positive or negative charges on an ion is shown as a superscript after the on an ion is shown as a superscript after the symbol for an atom or group of atoms symbol for an atom or group of atoms Hydrogen ions (HHydrogen ions (H++), Hydroxide ions (OH), Hydroxide ions (OH--)) Sodium ions (NaSodium ions (Na++), Chloride ions (Cl), Chloride ions (Cl--))

The pH (potential of Hydrogen) is the The pH (potential of Hydrogen) is the concentration of hydrogen ions in one liter of concentration of hydrogen ions in one liter of solution.solution.

Figure 2-5Figure 2-5

Compounds and Chemical FormulasCompounds and Chemical Formulas

Chemical formulas are shorthand ways to Chemical formulas are shorthand ways to show the atoms and ions in a chemical show the atoms and ions in a chemical compound. compound. Combining Hydrogen ions (HCombining Hydrogen ions (H++) and Hydroxide ) and Hydroxide

ions (OHions (OH--) makes the compound H) makes the compound H22O O

(dihydrogen oxide, a.k.a. water).(dihydrogen oxide, a.k.a. water). Combining Sodium ions (NaCombining Sodium ions (Na++) and Chloride ions ) and Chloride ions

(Cl(Cl--) makes the compound NaCl (sodium chloride ) makes the compound NaCl (sodium chloride a.k.a. salt).a.k.a. salt).

Organic Compounds: Carbon RulesOrganic Compounds: Carbon Rules

Organic compounds contain carbon atoms Organic compounds contain carbon atoms combined with one another and with various combined with one another and with various other atoms such as Hother atoms such as H++, N, N++, or Cl, or Cl--..

Contain at least two carbon atoms combined Contain at least two carbon atoms combined with each other and with atoms.with each other and with atoms. Methane (CHMethane (CH44) is the only exception.) is the only exception. All other compounds are All other compounds are inorganicinorganic..

Organic Compounds: Carbon RulesOrganic Compounds: Carbon Rules

HydrocarbonsHydrocarbons: compounds of carbon and : compounds of carbon and hydrogen atoms (e.g. methane (CHhydrogen atoms (e.g. methane (CH44)).)).

Chlorinated hydrocarbonsChlorinated hydrocarbons: compounds of : compounds of carbon, hydrogen, and chlorine atoms (e.g. carbon, hydrogen, and chlorine atoms (e.g. DDT (CDDT (C1414HH99CCl5l5)).)).

Simple carbohydratesSimple carbohydrates: certain types of : certain types of compounds of carbon, hydrogen, and oxygen compounds of carbon, hydrogen, and oxygen (e.g. glucose (C(e.g. glucose (C66HH1212OO66)).)).

Cells: The Fundamental Units of LifeCells: The Fundamental Units of Life

Cells are the basic Cells are the basic structural and structural and functional units of all functional units of all forms of life.forms of life. Prokaryotic cells Prokaryotic cells

(bacteria) lack a distinct (bacteria) lack a distinct nucleus.nucleus.

Eukaryotic cells (plants Eukaryotic cells (plants and animals) have a and animals) have a distinct nucleus.distinct nucleus.

Figure 2-6Figure 2-6

Macromolecules, DNA, Genes and Macromolecules, DNA, Genes and ChromosomesChromosomes Large, complex organic Large, complex organic

molecules (macromolecules) molecules (macromolecules) make up the basic molecular make up the basic molecular units found in living units found in living organisms.organisms. Complex carbohydratesComplex carbohydrates ProteinsProteins Nucleic acidsNucleic acids LipidsLipids

Figure 2-7Figure 2-7

States of MatterStates of Matter

The atoms, ions, and molecules that make up The atoms, ions, and molecules that make up matter are found in three physical states:matter are found in three physical states: solid, liquid, gaseous.solid, liquid, gaseous.

A fourth state, plasma, is a high energy A fourth state, plasma, is a high energy mixture of positively charged ions and mixture of positively charged ions and negatively charged electrons.negatively charged electrons. The sun and stars consist mostly of plasma.The sun and stars consist mostly of plasma. Scientists have made artificial plasma (used in Scientists have made artificial plasma (used in

TV screens, gas discharge lasers, florescent TV screens, gas discharge lasers, florescent light).light).

Matter QualityMatter Quality

Matter can be classified Matter can be classified as having high or low as having high or low quality depending on quality depending on how useful it is to us as how useful it is to us as a resource.a resource. High quality matter is High quality matter is

concentrated and easily concentrated and easily extracted.extracted.

low quality matter is more low quality matter is more widely dispersed and widely dispersed and more difficult to extract.more difficult to extract.

Figure 2-8Figure 2-8

CHANGES IN MATTERCHANGES IN MATTER Matter can change from one physical form to Matter can change from one physical form to

another or change its chemical composition.another or change its chemical composition. When a physical or chemical change occurs, no When a physical or chemical change occurs, no

atoms are created or destroyed.atoms are created or destroyed.• Law of conservation of matter.Law of conservation of matter.

Physical change maintains original chemical Physical change maintains original chemical composition.composition.

Chemical change involves a chemical reaction Chemical change involves a chemical reaction which changes the arrangement of the elements which changes the arrangement of the elements or compounds involved.or compounds involved.• Chemical equations are used to represent the Chemical equations are used to represent the

reaction.reaction.

Nuclear Changes: Radioactive DecayNuclear Changes: Radioactive Decay

Natural radioactive decay: unstable isotopes Natural radioactive decay: unstable isotopes spontaneously emit fast moving chunks of spontaneously emit fast moving chunks of matter (matter (alphaalpha oror beta particlesbeta particles), high-energy ), high-energy radiation (radiation (gamma raysgamma rays), or both at a fixed ), or both at a fixed rate.rate. Radiation is commonly used in energy production Radiation is commonly used in energy production

and medical applications.and medical applications. The rate of decay is expressed as a The rate of decay is expressed as a half-lifehalf-life (the (the

time needed for one-half of the nuclei to decay to time needed for one-half of the nuclei to decay to form a different isotope).form a different isotope).

Nuclear Changes: FissionNuclear Changes: Fission

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

Figure 2-9Figure 2-9

Nuclear Changes: FusionNuclear Changes: Fusion

Nuclear fusion: two isotopes of light elements Nuclear fusion: two isotopes of light elements are forced together at extremely high are forced together at extremely high temperatures until they fuse to form a heavier temperatures until they fuse to form a heavier nucleus.nucleus.

Figure 2-10Figure 2-10

ENERGYENERGY

Energy is the ability to do work and transfer Energy is the ability to do work and transfer heat.heat. Kinetic energy – energy in motionKinetic energy – energy in motion

• heat, electromagnetic radiationheat, electromagnetic radiation Potential energy – stored for possible usePotential energy – stored for possible use

• batteries, glucose moleculesbatteries, glucose molecules

Fig. 2-11, p. 43

Sun

Nonionizing radiationIonizing radiation

High energy, shortWavelength

Wavelength in meters(not to scale)

Low energy, longWavelength

Cosmicrays

GammaRays

X raysFar

infrared waves

Nearultra-violetwaves

VisibleWaves

Nearinfraredwaves

Farultra-violetwaves

Micro-waves

TVwaves

RadioWaves

Electromagnetic SpectrumElectromagnetic Spectrum

Organisms vary Organisms vary in their ability to in their ability to sense different sense different parts of the parts of the spectrum.spectrum.

Figure 2-12Figure 2-12

Fig. 2-13, p. 44

Low-temperature heat (100°C or less) for space heating

Moderate-temperature heat (100–1,000°C) for industrial processes, cooking, producing

steam, electricity, and hot water

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

Dispersed geothermal energyLow-temperature heat (100°C or lower)

Normal sunlightModerate-velocity windHigh-velocity water flowConcentrated geothermal energyModerate-temperature heat

(100–1,000°C)Wood and crop wastes

High-temperature heat (1,000–2,500°C)Hydrogen gasNatural gasGasolineCoalFood

ElectricityVery high temperature heat (greater than 2,500°C)Nuclear fission (uranium)Nuclear fusion (deuterium)Concentrated sunlightHigh-velocity wind

Source of Energy RelativeEnergy Quality

(usefulness)

Energy Tasks

ENERGY LAWS: TWO RULES WE ENERGY LAWS: TWO RULES WE CANNOT BREAKCANNOT BREAK

The first law of thermodynamics: we cannot The first law of thermodynamics: we cannot create or destroy energy.create or destroy energy. We can change energy from one form to another.We can change energy from one form to another.

The second law of thermodynamics: energy The second law of thermodynamics: energy quality always decreases.quality always decreases. When energy changes from one form to another, When energy changes from one form to another,

it is always degraded to a more dispersed form.it is always degraded to a more dispersed form. Energy efficiency is a measure of how much Energy efficiency is a measure of how much

useful work is accomplished before it changes to useful work is accomplished before it changes to its next form.its next form.