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APES Ch. 3 Notes
Science, Systems, Matter, and Energy
IX. Matter: Forms, Structure and Quality
Matter – anything that has
mass and takes up space. a. Elements – distinctive
building blocks of matter that make up every material substance.
b. Compounds – two or more elements held together by chemical bonds.
c. Mixture – a combination of two or more elements and compounds.
Gold (Au)Calcite (CaCO3)mixture
Building Blocks of Elements and Compounds
a. Atoms – smallest unit of matter that is unique to a particular element
b. Ions – electrically charged atoms or combinations of atoms
c. Molecules – combinations of two or more atoms of the same or different element held together by chemical bonds.
Forms of Matter
a. solid – most compact and orderly arrangement
b. liquid
c. gas – least compact and orderly arrangement
Fig. 3.5, p. 54
Energy absorbed
Melting
Freezing
EvaporationAnd boiling
Condensation
solid liquid gas
Energy released
Components of Atomsa. Proton – positively charged subatomic particle
with a mass of 1 (in nucleus)
b. Neutron- neutrally charged subatomic particle with a mass of 1 (in nucleus
c. Electron – negatively charged subatomic particle with a mass of 0 (outside nucleus)
Atomic Number – totalnumber of protons in an atom Atomic Mass – total number of protons and neutrons in an atom
HeMass # 4
Atomic # 2
Fig. 3.6, p. 55
Hydrogen (H)
0 n1 p
1e1 n1 p
2 n1 p
1e 1e
Mass number = 0 + 1 = 1Hydrogen-1(99.98%)
Mass number = 1 + 1 = 2Hydrogen-2or deuterium(0.015%)
Mass number = 2 + 1 = 3Hydrogen-3or tritium (T)(trace)
Uranium (U)
143 n92 p
143 n92 p
143 n92 p
146 n92 p
92e 92e
Mass number = 143 + 92 = 235Uranium-235(0.7%)
Mass number = 146 + 92 = 238Uranium-238(99.3%)
Atomic Number – total number of protons it an atom Atomic Mass – total number of protons and neutrons in an atom
Fig. 3.7, p. 56
PH – (pH) – measure of the concentration of hydrogen ions [H+] in a water solution.
Concentration=.001 = 10-3 = pH = 3
Chemical Formula – shows the number of atoms of each type in a compound.
C3H8 = methane
Organic Compounds – contain both carbon (C) and hydrogen (H)
a. Hydrocarbons
b. Chlorinated Hydrocarbons
c. Chlorofluorocarbons
d. Carbohydrates
e. Lipids
f. Proteins
g. Nucleic Acids
Inorganic Compounds – do not contain both carbon (C) and hydrogen (H), but may contain one or the other.
a. NaCl
b. H2O
c. N2O
d. NO
e. CO
f. CO2
g. NO2
h. SO2
i. NH3
j. H2S
k. H2SO4
l. HNO3
Matter Quality – measure of how useful a form of matter is to us as a resource, based on its availability of concentration.
• a. High Quality Matter – organized, concentrated, found near earth’s surface, and has great potential for use as a matter resource.
• b. Low Quality Matter – disorganized, dilute, deep underground or dispersed in oceans or the atmosphere, and has little potential for use as a matter resource.
• Entropy – measure of the disorder or randomness of a system or its environment
• Material Efficiency (resource productivity) – total amount of material needed to produce each unit of goods or services.
Fig. 3.9, p. 57
High Quality
Solid
Salt
Coal
Gasoline
Aluminum can
Low Quality
Gas
Solution of salt in water
Coal-fired powerplant emissions
Automobile emissions
Aluminum ore
Energy: Forms and Quality: • Energy – the capacity to do work (move something) and
transfer heat. • Kinetic Energy – the energy that matter has due to its
mass and speed or velocity. a. Windb. Flowing Streamsc. Heat (flowing from high to low)d. Electricitye. Electromagnetic Radiation f. Heat (total kinetic energy of all the moving atoms, ions,
or molecules within a given substance)g. Temperature (the average speed of motion of atoms,
ions, or molecules in a sample of matter at a given moment)
Potential Energy – the stored energy that is potentially available for use (can be changed into kinetic energy).
a. gasoline
b. rock at the top of a hill
c. nuclear energy
XIII. Two Laws of Energy
• Law of Conservation of Energy (First Law of
Energy or First Law of Thermodynamics) - in all physical and chemical changes, energy is neither created or destroyed, but it may be converted from one form to another.
• -energy input always equals energy output • -cannot get something for nothing in terms of
energy quantity
• Law of Conservation of Energy – We may change various forms of energy from one form to another, but in no physical or chemical change can we create or destroy any of the energy involved. (there is no away)
Energy can b changed from one form to another
Second Law of Energy or Thermodynamics• – when energy is changed from one form
to another, some of the useful energy is always degraded to lower quality, more dispersed, less useful energy.
- heat always flows spontaneously from hot (high quality energy) to cold (low quality energy).
• - we can not even break even in terms of energy, energy always goes from a more useful to less useful form.
• You cant break even
Fig. 3.18, p. 66
Solarenergy
Wasteheat
Chemicalenergy
(photosynthesis)
Wasteheat
Wasteheat
Wasteheat
Chemicalenergy(food)
Mechanicalenergy(moving,thinking,
living)
Energy efficiency
• Energy efficiency is the ratio of work that is done to the total amount of energy that was introduced into the system in the first place.
Energy Input – potential energy from gasoline
Energy Output-useful energy, kinetic which moves the car-waste energy, heat from friction, tires, brakes, sound
Energy efficiency is expressed in a percent, for example 70% efficient means 70% of energy is used to do work and 30% is lost as heat
• For example• Coal to electricty is 35% • Transport of electricity is 90%• Light bulb is 5% • Then when you burn coal the amoiunt of that
energy used to actually make light is• .35x.90x.05=.016 or 1.6%• 1.6% of the coal burned was used to make
light, 98.4% is lost as heat
Fig. 3.10, p. 58
Sun
High energy, shortwavelength
Low energy, longwavelength
Ionizing radiation Nonionizing radiation
Cosmicrays
Gammarays
X rays Farultraviolet
waves
Nearultraviolet
waves
Visiblewaves
Nearinfraredwaves
Farinfraredwaves
microwaves TVwaves
Radiowaves
Wavelengthin meters(not to scale)
10-14 10-12 10-8 10-7 10-6 10-5 10-3 10-2 10-1 1
Energy Quality – measure of an energy source’s ability to do useful work.
a. High energy quality – organized or concentrated and can perform much useful work.
b. Low energy quality – disorganized or dispersed and has little ability to do useful work.
Fig. 3.11, p. 59
ElectricityVery high temperature heat (greater than 2,500°C)Nuclear fission (uranium)Nuclear fusion (deuterium)Concentrated sunlightHigh-velocity wind
High-temperature heat (1,000–2,500°C)Hydrogen gasNatural gasGasolineCoalFood
Normal sunlightModerate-velocity windHigh-velocity water flowConcentrated geothermal energyModerate-temperature heat (100–1,000°C)Wood and crop wastes
Dispersed geothermal energyLow-temperature heat (100°C or lower)
Very high
High
Moderate
Low
Source of Energy Relative Energy Quality(usefulness)
Energy tasks
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
• Law of Conservation of Matter – We may change various elements and compounds from one physical or chemical for to another, but in no physical or chemical change can we create or destroy any of the atoms involved. (there is no away)
XII. Nuclear Changes – occur when nuclei or certain isotopes spontaneously change into one or more different isotopes.• Natural Radioactive Decay – a nuclear change in which
unstable isotopes (radioactive isotopes or radioisotopes) spontaneously emit fast moving chunks of matter called particles, high energy radiation, or both at a fixed rate.
a. Gamma Rays – a form of high energy electromagnetic
radiation (ionizing energy)b. Alpha Particles – fast moving positively charged chunks
of matter consisting of 2 protons and two neutrons 9 (ionizing particle), harmful when inhaled or ingested, can cause skin cancer.
c. Beta Particles – High speed electrons (ionizing particle), can damage internal organs even when not ingested or inhaled.
Waves
2 protons & 2 neutrons
Negative particle like an electron
Fig. 3.12, p. 62
Sheet of paper
Block of wood
Concretewall
Alpha
Beta
Gamma
Radioactive decay series of Uranium
• Half Life – the time needed for one half of the nuclei in a radioisotope to decay and emit their radiation to form a different isotope (results in a series of different radioisotopes until a non-radioactive isotope is formed)
Fig. 3.13, p. 62
Fra
ctio
n o
f o
rig
inal
am
ou
nt
of
plu
ton
ium
-239
left
1
1/2
1/4
1/8
0240,000 480,000 720,000
Time (years)
1sthalf-life
2ndhalf-life
3rdhalf-life
Fig. 3.14, p. 63
Radon55%
Other1%
Consumerproducts
3%
Nuclearmedicine
4%
MedicalX rays10%
Thehumanbody11%
Earth8%
Space8%
Natural sources 82%
Human-generated 18%
Effects of Ionizing Radiation• Causes: • 1. Penetrating a Cell• 2. Altering a cellular chemical by knocking an
electron loose.• 3. altering molecules needed for normal
chemical functioning • Types: • 1. Genetic Damage – mutations to DNA
molecules that alter genes and chromosomes. (possibly passed to following generations)
• 2. Somatic Damage – to tissues, which cause harm during a lifetime (burns, cancers)
Effects of Ionizing radiation
Effects of Nonionizing Radiation (Electromagnetic Radiation)• – Not Known• Sources:• 1. Power Lines• 2. Electrical Appliances • Possible Effects:• 1. Cancer (childhood leukemia, brain
tumors, breast cancer)• 2. Miscarriages• 3. Birth Defects• 4. Alzheimer’s Disease
Effects of Cell Phones
Useful Applications of Radioisotopes 1. Radiocarbon Dating – estimates
age of carbon containing substances from dead plants and animals.
2. Tracers – in pollution detection (pipelines)
3. Nuclear Medicine – diagnosis and treatment of disease (cancer)
Fig. 3.15, p. 64
Fission fragment
Fission fragment
Energy
n n
n
n
Uranium-235nucleus
Unstablenucleus
Fig. 3.16, p. 64
n
U23592
9236 Kr
Ba14156
n
n
n
9236 Kr
U23592
U23592
Ba14156
9236
Kr
Ba14156
9236
Kr
Ba14156
n
n
n
n
n
n
n
n
U23592
U23592
U23592
U23592
n
Fig. 3.17, p. 64
Fuel Reaction Conditions Products
D-T Fusion
Hydrogen-2 ordeuterium nucleus
Hydrogen-3 ortritium nucleus
Hydrogen-2 ordeuterium nucleus
Hydrogen-2 ordeuterium nucleus
D-D Fusion
+
+
+
+
Neutron
Energy
+ +
Helium-4nucleus
+ +
Helium-3nucleus
Energy
Neutron
++
+ +
100 million ˚C
1 billion ˚CNeutron
Proton+
