Science, Systems, Matter, and EnergyScience, Systems, Matter, and Energy

G. Tyler Miller’sLiving in the Environment

13th Edition

Chapter 3

G. Tyler Miller’sLiving in the Environment

13th Edition

Chapter 3

Dr. Richard ClementsChattanooga State Technical Community CollegeCharlotte Kirkpatrick

Dr. Richard ClementsChattanooga State Technical Community CollegeCharlotte Kirkpatrick

Key Concepts

Science as a process for understanding

Components and regulation of systems

Matter: forms, quality, and how it changes; laws of matter

Nuclear changes and radioactivity

Energy: forms, quality, and how it changes; laws of energy

Science, and Critical Thinking

Scientific data: facts, observations and measurements

Scientific (natural) laws: description of what we see happening over and over again in nature. Highly reliable

Consensus science vs. Frontier science

Scientific theories:widely accepted explanations of data and laws; high degree of certainty, supported by extensive evidence

Scientific hypotheses: tentative explanation that explains scientific data and makes predictions; testable

Fig. 3-2 p. 41

Science, and Critical Thinking: Consensus vs. Frontier Science

Consensus science: data, theories , and laws; widely accepted

Frontier science: Preliminary results; untested, scientific “breakthroughs”

Reputable scientists question and disagree about the meaning and accuracy as well as the validity of the hypothesis

Science, and Critical Thinking: Inductive vs. Deductive Reasoning

Inductive Reasoning: Using specific observations and measurements to arrive at a general conclusion or hypothesis

“Bottom-up” reasoning: specific to generalVery high probability or degree of certainty that it is true

Deductive Reasoning:Using logic to arrive at a specific conclusion based on a generalization or premise

“Top-down” reasoning: general to specificConclusions are valid if the premise is correct and we do not use faulty logic to arrive at the conclusion

Intuition, imagination, and creativity are also important to

science discovery.

What Scientists Do.Ask a question

Do experimentsand collect data

Formulatehypothesis

to explain data

Do moreExperiments totest hypothesis

Revise hypothesisif necessary

Well-tested andaccepted

hypothesesbecome

scientific theories

Interpret data

Well-tested andaccepted patternsIn data becomescientific laws

Fig. 3-2 p. 41

Systems:

A set of components that

1. function and interact in some regular and theoretically predictable manner and

2. be isolated for the purposes of observation and study

The environment has many interacting systems involving living and nonliving things

Models and Behavior of Systems

Inputs: such as matter, energy or information into a system

Flows (throughputs):of matter, energy, or information within a system at certain rates.

Stores (storage areas):within a system where matter,energy, or information can accumulate for various lengths of time before being released.

Outputs:matter,energy or information that flows out of the system into sinks in the environment.

Why use Models?1. Find out how systems work

2. Evaluate which ideas or hypotheses work

• Some of the most powerful models are mathematical models.

• Models are only as good as the assumptions built into them and

• The data fed into them to make projections about the behavior of a complex system.

System Regulation/ Feedback Loops

Positive Feedback: Change in a certain direction that causes further change in the same direction

Negative Feedback: One change leads to a lessening of that change

Feedback Loops: Occurs when an output of matter, energy, or information is fed back into the system as an input that changes the system

Most systems contain one or a series of coupled positive and negative feedback loops

System Regulation

Time Delay: Delay between input of a stimulus and the response to it.

Time delays allow a problem to build up slowly until it reaches a threshold level and causes a fundamental shift in the behavior of a system.

ex. Pop. Growth, leaks from toxic waste dumps, etc.

Synergy: when two or processes interact so the combined effect is greater than the sum of their separate effects.

Systems/ Coupled Feedback Loops: Homeostasis

Fig. 3-3 p. 46

Homeostasis: Maintenance of internal conditions in a system despite fluctuations in the internal environment

Law of Conservation of Problems

• The technological solution of one problem usually creates one or more new unanticipated problems

Anticipating Environmental Surprises

• We can never do one thing: any action in a complex system has multiple and often unpredictable effects.

Results from:

• Discontinuities due to a breaching of an environmental threshold

• Synergistic interactions

• Unpredictable, chaotic events

Solar Water Heater ProjectSolar Water Heater Project• Purpose: In a group of no more than 3 you will

design, build and test a passive solar water heater. • Design: this is your hypothesis, so it must be

researched and based on known information or evidence from other research. You must include a written description of the process you went through to come up with the hypothesis, including your research information.

• Include a diagram of your design and a list of materials

• Procedure: Identify the procedures you went through to build the project (pictures must be included that show the group working together in the process). In addition, include a journal of the steps as well.

Solar Water Heater ProjectSolar Water Heater Project• Testing: Identify your controlled, manipulated and

responding variables then perform at least 3 tests of your design. One test may be the final one done at school. Alterations may be performed to modify your design (hypothesis), but they must be documented.

• Data: keep a data table for a control and your experimental design. Be sure to include data at multiple intervals, not just beginning temp and ending temp.

• Analysis: Look at your data and rework the data into a graph or some other way to analyze the data other than a chart of numbers. Determine what the data tells you.

• Conclusion: is your design/hypothesis efficient at heating water and if it is not why and what would you do to improve it. Were there any experimental errors you could identify?

Solar Water Heater ProjectSolar Water Heater Project• Reporting: You may turn in only one report

but each person in the group must have contributed equally in all aspects of the project. In other words; you can not have one person design it, another person build it and another person write up the report; you must all be involved at all steps in the process.

• We will have the final testing day as close to two weeks from Friday as possible, all depending on weather, so keep track of the weather report. I will give you at least a day notice as to when you need to bring in your project for the final testing.

Matter: Forms, Structure, and Quality

Elements

Compounds

Mixtures

Molecules

Atoms

Subatomic ParticlesProtonsNeutronsElectrons

Atomic Characteristics

Atomic number Ions

Atomic mass Isotopes

Examples of Atoms

Fig. 3-4 p. 48

Chemical Bonds

Chemical formulas

Ionic bonds: transfer of electronsCovalent bonds: share electrons, with in a molecule

Hydrogen bonds: bonds between molecules

Organic Compounds

• Carbon containing compounds

• Carbon in bonds with itself and one or more other elements like; H, O, N, S, P, Cl, and Fl

• May be natural or synthetic

• Do not have C-C or C-H bonds

• Ex. NaCl, H2O, N2O, NO, CO, CO2 , NO2, SO2, NH3, H2S, H2SO4, HNO3

Organic vs. inorganic compounds

Organic Compounds

Hydrocarbons:compounds of carbon and hydrogen atoms. Ex. Methane CH4

Chlorinated hydrocarbons: compounds of chlorine, carbon and hydrogen atoms. Ex. DDT and PCB’s

Chlorofluorocarbons (CFC’s): compounds of carbon, chlorine and fluorine atoms. Ex. Freon-12

Organic Compounds/ Polymers and MonomersSimple carbohydrates: Monomers,compounds of carbon and hydrogen and oxygen. Ex. GlucoseBuilding block for larger polymers of complex carbohydrates. Ex. Starch

Nucleotides: monomers also composed of C, H, O, N for the larger polymers of Nucleic Acids (RNA and DNA)

Amino Acids: monomer composed of C, H, O, N for the larger polymer of Proteins

Genetic Material

Nucleic acids Genes

Gene mutationsChromosomes

Fig. 3-6 p. 50

The Four States of Matter

SolidLiquidGas

Plasma: not a physical state of matter but composed of a high energy mixture of roughly equal numbers of positively charged ions and negatively charged electrons.

Fig. 3-7 p. 50

The three physical states of Matter

Differ by spacing and orderliness of its atoms, ions, or molecules

Matter Quality and Material Efficiency

Fig. 3-8 p. 51

High-quality matter:Concentrated, close to surface, useful Low-quality matter: dilute,deep underground, not so useful Entropy: A measure of the disorder or randomness in a closed system. Material efficiency

(resource productivity)

Energy: Forms

Kinetic energy Potential energy

Fig. 3-9 p. 52

Heat

Electromagnetic spectrum

Transfer of Heat Energy

Fig. 3-11 p. 553

Convection Conduction Radiation

Heat from a stove burner causes atoms or molecules in the pan’sbottom to vibrate faster. The vibrating atoms or molecules then collide withnearby atoms or molecules, causingthem to vibrate faster. Eventually, molecules or atoms in the pan’shandle are vibrating so fast itbecomes too hot to touch.

As the water boils, heat from the hot stove burner and pan radiate into thesurrounding air, even though airconducts very little heat.

Heating water in the bottom of a pancauses some of the water to vaporizeinto 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.

Heat: the total kinetic energy of all the moving atoms, ions, or molecules within a given substance.

Energy: Quality

Fig. 3-12 p. 53

High-quality energy: concentrated and performs useful work

Low-quality energy: dispersed and does little useful work

Physical and Chemical Changes

Fig. In text p. 54

The Law of Conservation of Matter

Matter is not consumed

Matter only changes form

There is no “away”

Matter and Pollution

Chemical nature of pollutants: How active and harmful it is to living organisms

Concentration: the amount per unit volume of Air, water, soil, or body weight

Persistence: How long it stays in the air, water, soil or body

Categories of Pollutants Based on Persistence Degradable (nonpersistent) pollutants: broken down completely by natural physical, chemical, and biological processes

Biodegradable pollutants: degradable pollutants that are broken down by bacteria

Slowly degradable (persistent) pollutants: Take decades or longer to decay. Ex. DDT and most plastics

Nondegradable pollutants:cannot be broken down by natural processes. Ex. Lead mercury, arsenic

Nuclear Changes

Radioactive isotopes (radioisotopes):unstable isotopes that emit high energy radiation or fast moving particles or both at a fixed rate.

Gamma rays: High energy EM radiation

Alpha particles: fast-moving positively charged matter consisting of two protons and two neutrons

Beta particles: high speed electrons

Penetrating ability of the 3 types of ionizing radiation emitted by radioactive isotopes

Fig. 3-13 p. 56

Nuclear Changes

Half life (See Table 3-2 p. 56): amount of time it takes for one-half of the nuclei in a radioactive isotope to decay and emit their radiation to form a different isotope

Slide 17Slide 17

Frac

tion

of o

rigin

al a

mou

nt o

fpl

uton

ium

-239

left

1

1/2

1/4

1/8

0240,000 480,000 720,000

Time (years)

1sthalf-life

2ndhalf-life

3rdhalf-life

Figure 3-14Page 56

Nuclear Changes

Ionizing radiation:

How much? Not too much most of it is background and natural. Usually the excess comes from medical X-rays and diagnostic tests

Effects:genetic damage and somatic damage

Slide 19Slide 19

Radon55%

Other1%

Consumerproducts

3%

Nuclearmedicine

4%

MedicalX rays10%

Thehumanbody11%

Earth8%

Space8%

Natural sources 82%

Human-generated 18%

Figure 3-15Page 57

Nuclear Reactions

• Nuclei of certain isotopes with large mass numbers are split apart into lighter nuclei when struck by neutrons; each fission releases two or three neutrons and energy.

• Each of these neutrons, in turn, can cause additional fission.

• There must be a critical mass of the fissionable material for the multiple fissions to take place. This is known as a Chain Reaction.

Fission

Fig. 3-16 p. 57

Ways of Using Nuclear Fission• Atomic Bomb: Uncontrolled nuclear fission caused by

the release of an enormous amount of energy.

An explosive charge forces two fissionable masses together so that the critical mass may be reach and a chain reaction can take place.

• Nuclear Power Plant: Controlled nuclear fission so that the chain reaction only uses one of every two or three neutrons to split another nucleus.

The splitting of a nuclei causes the release of heat to produce steam to power a turbine.

Nuclear Reactions• Nuclear change in which to

smaller nuclei (such as H) are forced together at extremely high temperatures until they form a heavier nucleus and excess energy is released.

• Fusion of HHe is the source of energy in the sun.

• Hydrogen weapons form D-T fusion reaction.

• Attempts to have controlled Fusion for energy purposes are still in the experimental phase

Fusion

Fig. 3-17 p. 58

Laws Governing Energy Changes

Energy is neither created nor destroyed

Energy only changes form

You can’t get something for nothing

First Law of Thermodynamics (Energy)

ENERGY IN = ENERGY OUT

Laws Governing Energy Changes

Second Law of Thermodynamics In every transformation, some energy is

converted to heat (lower quality)

You cannot break even in terms of energy quality (always goes from more useful to less useful form)

Always end up with less energy than we started with. Energy Efficiency will never be 100%.Cannot recycle or reuse

2nd Law of Thermodynamics

Slide 23Slide 23

Solarenergy

Wasteheat

Chemicalenergy

(photosynthesis)

Wasteheat

Wasteheat

Wasteheat

Chemicalenergy(food)

Mechanicalenergy(moving,thinking,

living)

Figure 3-19Page 60

Connections: Matter and Energy Laws and Environmental Problems High-throughput (waste) economy: advanced industrialized nations, increase economic growth through increase flow of matter and energy resources

Fig. 3-20 p. 60; see Fig. 3-21 p. 61

Matter-recycling economy:allow economic growth without depleting matter resources or increases pollution

Low-throughputeconomy:

Sustainability based on energy flow and matter recycling

Low Throughput Economy

Slide 26Slide 26

Inputs(from environment)

SystemThroughputs

Outputs(from environment)

High-qualityenergy

Matter

Pollutionprevention

byreducing

matterthroughput

Sustainablelow-wasteeconomy

Recycleand

reuse

Pollutioncontrol

bycleaningup some

pollutants

Matteroutput

Low-qualityenergy(heat)

Wastematter

andpollution

MatterFeedback

Energy Feedback

Figure 3-21Page 61