Notes

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I. ENERGY
•
Common: Heat, light, and electricity
•
Other forms: mechanical energy,
chemical energy, and nuclear energy.
•
These forms of energy meet the energy
needs of the people on Earth.
ENERGY
 Energy
cannot be created or
destroyed
 Energy
 The
can, however, be changed
storage, transfer, and conversion
of energy is the driving forces behind
all life on Earth
A. THE NEED FOR ENERGY
1.
2.
3.
A fuel is any substance from which
energy can be obtained
Electricity is generated by the
conversion of other forms of energy
This conversion is not 100 percent
efficient.
• Some energy is converted to heat,
light, or sound
THE NEED FOR ENERGY
Non-renewable resource – a
resource that is used faster than it is
replaced in nature
 Ex. Fossil Fuels, Sand, Metals
 4.
Renewable Resource – a
resource that is replaced in nature
faster than it is used.
 Ex. Oxygen, Carbon Dioxide, Water
 5.
B. Changing Energy Needs
1.
Hunter-gatherer societies
○ Light, heat, and cooking
○ Wood met needs
Changing Energy Needs
 2. Agricultural
societies
 Domesticated animals
○ energy sources for plows and
other farm equipment
Changing Energy Needs
•
3. Industrial Revolution
• Machines take over tasks
○ Farm equipment: horse-drawn plow
gave way to tractors and harvesters
 Fuel
consumption increases due to
manufacturing and use of machines
C. Organic Fuels
Organic Fuels:
1.
a.
b.
c.
•
Contain carbon
Were once part of living organisms
Also contain hydrogen
2. A compound composed only of
carbon & hydrogen is called
a hydrocarbon
Organic Fuels
3.
Hydrocarbons may contain
impurities
 other chemicals, such as sulfur or
lead compounds
 Impurities contribute to the pollution
4. Fossil Fuels
 Stored
energy from ancient organisms
can be used today as fuel source
 Ex.
Oil, Coal, Natural Gas
D. Coal
plants + swamps + sediment + time = Coal
 Formed
when ancient plant material is
compressed below sediment
 Rock
that is an organic fossil fuel
Coal

Heat & pressure:
 Forces out water
 Increases the carbon concentration

Increased carbon concentration means
Increased energy and less smoke
released during combustion.
1. Stages in Coal formation
1.
Peat
2.
Lignite
3.
Bituminous Coal
4.
Anthracite
a. Peat
 Found on Earth’s surface
 Compressed plant material
 High water concentration
 Low energy production
 Burns smoky
 Brittle and brown
 Low carbon concentration
 Resembles decaying wood
b. Lignite
• Compressed peat
• Lower water concentration
• Soft brown coal (40% carbon)
• Releases little smoke and burns quick
• Found below surface - Mined
c. Sub-bituminous coal
Type of coal whose properties range from
those of lignite to those of bituminous coal
 Used primarily as fuel for steam-electric
power generation

d. Bituminous coal
 Soft black coal
 Most abundant in USA
 Forms deep below surface – Mined
• Less water & fewer impurities than
lignite
• Higher carbon concentration (85%)
• Releases little smoke and burns hotter
than lignite
• Widely used in industries - power plants
d. Anthracite coal
 Metamorphic rock
 Shiny black color
 Least water, fewest impurities
 Highest carbon concentration (95%)
 Located deeper in the ground than any
of the other forms of coal
 Burns the hottest with the least amount
of smoke
 Most expensive
E. PETROLEUM AND NATURAL GAS
 Fossil
fuels can occur in the three
phases of matter.
 Coal - solid
 Petroleum - liquid
 Natural Gas - gas
1. Petroleum
organic material + shallow seas + sediment
+ time = Petroleum
•
•
Syrupy black liquid fossil fuel
Formed from ancient plankton and other
microscopic protists, plants, and animals
•Impermeable - water & other
liquids cannot pass through it.
•Permeable – water & other
liquids can pass through it.
Impermeable Shale
Permeable Sandstone
Impermeable Shale
Oil Wells
•
Pressure builds up
•
Gusher: drilled well into a
pressurized pool of oil - shoot
upward
•
Where there is little or no pressure,
oil must be pumped to the surface
a. Petroleum
•
One of the world's most important
resources
• Separated or refined to make a
variety of products
• Gasoline
• Jet fuels
• Motor oil
• Heating oil
• Kerosene
Petroleum examples cont’
 Grease
and lubricants used to
reduce friction are petroleum byproducts
 The
asphalt, synthetic fabrics,
and plastics are also made from
petroleum
Petroleum
b. Worldwide
population
increases
so does the
demand for
petroleum
2. Natural Gas
a.
Mixture:
 Methane - major hydrocarbon
 Ethane - minor hydrocarbon
 Propane -minor hydrocarbon
 Trace amounts of:
○ Hydrogen sulfide
○ Carbon dioxide
○ Nitrogen
○ Helium
Natural Gas
b. Use:
 Industry
 Homes and businesses for heating
– burns cleaner
 Household appliances
 Does not have to be converted to
electricity first; more efficient
Natural Gas
 Household
appliances Ex.
 Stoves
 Water heaters
 Clothes dryers
Natural Gas
c. Natural gas forms in much the same
way as petroleum
 Often found trapped above
petroleum pools
 Sometimes viewed as waste of
drilling oil
Homework Review - Homework
Compounds that contain only carbon and
hydrogen are
(a) fuels;
(b) fossil fuels;
(c) organic fuels;
(d) hydrocarbons.
Homework Review - Homework
Energy conversion is not 100% efficient
because energy is lost in the form of
(a) light
(b) heat
(c) sound
(d) all of the above
Homework Review - Homework
The type of society that has the greatest
energy needs is the
(a) hunting society;
(b) gathering society;
(c) industrial society;
(d) agricultural society.
Homework Review - Homework
The first stage in the formation of coal is
(a) lignite;
(b) peat;
(c) anthracite;
(d) bituminous coal.
Homework Review - Homework
The type of coal that has the highest
carbon content is
(a) peat;
(b) lignite;
(c) bituminous coal;
(d) anthracite.
Homework Review - Homework
The most abundant form of coal in the
United States is
(a) peat;
(b) lignite;
(c) anthracite;
(d) bituminous coal.
Homework Review - Homework
Coal is to fossil fuel as
(a) Petroleum is to crude oil
(b) Peat is to coal
(c) Methane is to swamp gas
(d) Alcohol is to biomass fuel
Homework Review - Homework
Crude oil is another name for
(a) alcohol;
(b) methane;
(c) peat;
(d) petroleum.
Homework Review - Homework
Petroleum: plastics as
(a) alcohol: gasoline;
(b) coal: carbon;
(c) garbage: electricity;
(d) industry: fuels.
Homework Review - Homework
Mines: coal as
(a) petroleum: refineries;
(b) corn: alcohol;
(c) land: agriculture;
(d) wells: petroleum
Homework Review - Homework
The use of corn to make alcohol is an
example of
(a) bioconversion;
(b) fossil fuels;
(c) hydrocarbon;
(d) refining.
Homework Review - Homework
Of the following the only example of a
biomass fuel is
(a) coal;
(b) petroleum;
(c) wood;
(d) natural gas.
Homework Review - Homework
The process by which alcohol is made by
yeast is called
(a) fermentation;
(b) bioconversion;
(c) purification;
(d) distillation.
Homework Review - Homework
Unlike fossil fuels, biomass fuels
(a) do not release carbon dioxide;
(b) are renewable resources;
(c) are buried beneath the surface;
(d) are not products of living things.
OTHER ORGANIC FUELS
 OBJECTIVES:
 Describe
some of the problems
associated with the use of fossil fuels
 Compare
biomass fuels to fossil
fuels, and give an example of a
bioconversion technique
F. Problems associated with the
use of fossil fuels
1. availability & pollution
○ The availability problem
 fossil fuels are not renewable
 All available - have already formed
Problems with Fossil Fuels cont’
•
Coastal states and offshore drilling
• risk of environmental damage
• oil spills
• widespread habitat alteration
Problems with Fossil Fuels
 An
alternative - depend on the oil
that are already known to exist
 Location, Location, Location…
 Operation
Desert Storm - supply
and demand
Problems with Fossil Fuels
3.
Pollution
• various kinds, especially air pollution
a. release carbon dioxide
4.
5.
Increased use of fossil fuels since the
Industrial Revolution – increased carbon
dioxide in the atmosphere by more than
20% –
Greenhouse Effect
Problems with Fossil Fuels
Obtaining fossil fuels is Dangerous
6. Natural gas – combustible
7. Coal miners
 Suffocation by natural gas
 Explosions of natural gas and coal
dust
Coal Mine Explosion
G. Biomass Fuels
1.
A fuel formed from the
products of living
organisms.
2.
Ex. wood,
garbage,
methane,
and alcohol
3. Renewable Resource –
Can be produced
4. Wood
Cheap, used mostly in developing
nations
• Cost and availability
1. Large amounts of time spent
searching
b. Smoke and high carbon dioxide
c. Can be damaging to natural forests
a.
5. Garbage
a. Much is largely organic materials
b. About two-thirds can be burned
c. Heat water
d. Produce steam
• Turn turbines
• Bingo… electric
6. Methane
a.
Swamp gas:
• produced in swamps
• from decaying plants
• naturally produced form of methane
b.
Decaying garbage in dumps also
produces methane
c.
Methane removed from swamps and
garbage dumps is used as a fuel
7. Alcohol
Bioconversion : the conversion of
organic materials into fuels
a.
• Ex. Sugar cane or corn to make alcohol
Ethanol
b.
• Yeast – Fermentation
i.
Liquid biomass fuel
Burns cleanly
& Renewable
Alcohol
•
ii.
•
Brazil - 2 million cars fueled by
ethanol
Gasohol is a mixture of 90 percent
gasoline to I0 percent ethanol
Future: Engines that run on alcohol
made from sunflower or peanut
Objective Revisited
 Describe
some of the problems
associated with the use of fossil
fuels and what you think should
be done to overcome these
problems
Objective Revisited
 Compare
biomass fuels to fossil
fuels, and give an example of a
bioconversion technique
Covalent and Ionic Bonding
II. ATOMS AND RADIOACTIVITY
Atoms – Basic building blocks
of matter
 Composed of:
A.
1. Protons
2. Neutrons
Nucleus
3. Electrons
 Neutral Atom
# of p+ = # of e-
The Atom
Subatomic
Particle
Location Charge Mass
(amu = atomic mass unit)
Proton (p+)
Nucleus
+
1 amu
Neutron (n0)
Nucleus
Neutral
1 amu
Electron (e-)
Outside
Nucleus
-
~0 amu
Helium
1 Å = 1 ten billionth of
a meter
B. Atoms and Isotopes
AII atoms of the same element have
the same number of protons in their
nuclei.
1.
a.
b.
Atomic Number - # of p+
Ex. O = 8 protons /atomic number is 8
Atomic Mass/ Mass # = # of protons
& neutrons in the nucleus of an atom
Atoms and Isotopes
c.
Individuals atoms of the same
element may have different mass #’s
because the # of neutrons in the
nucleus can vary.
d.
Isotope : same element but different
mass number – different number of
neutron.
Isotopes
Ions vs. Isotopes
Change in Number
of Electrons
Change in the
Number of Neutrons
- No change in mass - Change in mass
- Change in charge - No change in
- Formation of an ion charge
- Formation of an
isotope
C. Radioactivity
– unstable isotopes of
atoms, emitting particles & energy
from their nuclei as they decay
 Radioactivity

Studied by Marie Curie

Ex. H-1 is not radioactive, nor is H-2.
H-3 is radioactive.
2. Three Types of Radiation
a.
Alpha particles are made up of
two protons and two neutrons
b.
A beta particle is a high-speed
electron.
c.
Gamma rays are a form of
electromagnetic radiation
Radioactivity
 Alpha
decay process changes
one element into another
3)
Half-life : the amount of time it
takes for half of the atoms in a
sample of a radioactive element
to decay
Objective Revisited
 Describe
the structure of the
atom and the atomic nucleus.
Draw an image of a planetary
model of an atom and a electron
cloud model. Make sure to label
the three subatomic particles and
give the charge and mass for
each.
D. REACTIONS AND REACTORS
1.
Energy holds protons and
neutrons together
2.
Nuclear Fission- splitting the
atom; releases energy
a.
Can be used to Generate
electricity
Nuclear Fission
b.
i.
ii.
Uranium-235 most used
Splits when struck by a neutron
When U-235 splits, it releases
energy & forms new nuclei, called
Daughter nuclei
• Often barium or krypton
• Often radioactive
E. Nuclear Reactors
Nuclear reactors function very similarly to
fossil fuel power plants.
2. Energy is released by nuclear reaction
1.
 Energy is heat
 Heat boils water
 Steam Rises
 Steam Turns Turbines
 Generates Electricty
Look Familiar?
How About Now?
Nuclear Reactors
3. Water:
a. Acts as a coolant preventing the
core from melting
b. Slows the movement of the
neutrons released during the chain
reaction
Nuclear Reactors
c. control rods
 regulate the speed of the chain
reaction
i. made of cadmium, boron, or other
materials
○ absorb neutrons
○ regulate heat production

coolant water may reach temperatures
above 275 °C
Nuclear Fission vs. Nuclear Fusion
RADIOACTIVE WASTE
•
OBJECTIVES
– Define radioactive waste, and
explain the dangers that arise
from it.
– State the problems involved in
the safe disposal of radioactive
wastes.
F. RADIOACTIVE WASTE
1. Produced by Nuclear power
plants
 ~32 metric tons typical nuclear/year
○ Reprossessed into 1.5 tons of extremely
radioactive – Dangerous
 Large amounts of low-level waste
RADIOACTIVE WASTE
•
Radiation is unhealthy for living
things
•
Actively dividing cells
• blood-cell producing bone marrow
• skin cells
RADIOACTIVE WASTE
 Radiation Exposure
 Large doses
○ including skin burns
○ anemia
○ death
 Changes in DNA
○ long-term effects
○ cancer
○ genetic mutations
RADIOACTIVE WASTE
4. Radiation exposure
 measured in rems
 Average
○ 0.2-0.5 rems / year
RADIOACTIVE WASTE
 Background
radiation mostly comes
from naturally occurring elements in
our surroundings
 Radiation
exposure varies widely,
depending on where a person lives
and where he or she works
G. Types of Waste
1. High-level waste
 Radioactive wastes that emit large amounts
of radiation
 used uranium fuel rods
 control rods
 water used to cool and control the chain
reactions
a. Very Dangerous – May Also Be Poisonous
b. May be radioactive for tens of thousands of
yrs
Types of Waste
2. Medium-level and low-level wastes:
 Not as radioactive as high-level wastes
 larger volume of these wastes is
generated
• Ex.
• mine wastes scattered around a
uranium mine
• contaminated protective clothes of a
power plant worker
Types of Waste
•
Low-level radioactive wastes
• Also produced by hospitals & laboratories
• Less obvious damage to health than high-
level wastes
• More common than high level wastes
• May pose a greater health risk to human
health
H. Waste Disposal
•
The contaminants may have long
half-lives, taking thousands of
years to decay
•
Low-level wastes can be
dangerous for 300 years or more
H. Waste Disposal
1. High-level wastes may be
dangerous for tens of thousands
of years
•
Plutonium-239
• half-life of 24,000 years
• dangerous for 192, 000 years
• deadly poison, even in small amounts
Waste Disposal
2. Long half-lives = serious disposal
problem
3. Must be sealed in containers that will not
corrode for thousands of years
4. U.S. government seal the wastes in glass
a. must be geologically stable
b. Earthquake or Volcanoes could cause spill
c. Must be stored deep under the ground
(costly)
Waste Disposal
•
Almost all the high-level radioactive
wastes in the world have not been
disposed of permanently
•
They sit in storage tanks outside
nuclear power and weapons plants
Waste Disposal
•
In many cases, these tanks have
begun to leak, contaminating the
groundwater and releasing
radioactive wastes into the
environment
Waste Disposal
 These
wastes must be permanently
removed before the contamination
gets worse
 The
government predicts that the
cleanup of 20 of the most
contaminated nuclear weapons sites
in the United States could cost $600
billion
Waste Disposal
 Low-level wastes
 pose disposal problems
 often buried
 enclosed in concrete and dropped into the
ocean
 Exposes environment to contamination
 Medium-level wastes
• have not been disposed of permanently
• presents many of the same problems as
high-level wastes
I. Safety and Cost
•
If the cooling and control systems in
a reactor core fail, the chain reaction
can no longer be controlled
•
The core will grow hotter, causing the
fuel rods and even the reactor vessel
to melt
• Meltdown
Safety and Cost
 Full
meltdown
• release huge amounts of radiation
• plants are built to avoid meltdowns
or contain them if they occur
• In April I986, however, one core of the
Chernobyl nuclear power plant in
Ukraine did melt down
 The
Chernobyl plant was old and
lacked many of the safety features
built into newer plants
 The
accident itself was caused by
human error
 The
severity of this accident and the
problems with radioactive waste
disposal has led many people to
question the wisdom of using nuclear
power
 Nuclear
power plants are also very
expensive because the required
safety measures are very costly
Homework Review
Protons and neutrons are found together in
the part of the atom called the
(a) alpha particle;
(b) electron;
(c) nucleus;
(d) isotope.
Homework Review
Protons and neutrons are found together in
the part of the atom called the
(a)
(b)
(c) nucleus;
(d)
Homework Review
Two atoms of the same element with
different mass numbers are called
(a) isotopes;
(b) nuclei;
(c) electrons;
(d) neutrons.
Homework Review
Two atoms of the same element with
different mass numbers are called
(a) isotopes;
(b)
(c)
(d)
Homework Review
One kind of radiation not released by
radioactive decay is
(a) alpha particles;
(b) free protons;
(c) beta particles;
(d) gamma rays.
Homework Review
One kind of radiation not released by
radioactive decay is
(a)
(b) free protons;
(c)
(d)
Homework Review
All isotopes of an element contain the
same number of neutrons.
TRUE or FALSE
Homework Review
All isotopes of an element contain the
same number of neutrons.
FALSE, Protons
Homework Review
Beta particles contain two protons and two
neutrons.
TRUE or FALSE
Homework Review
Beta particles contain two protons and two
neutrons.
FALSE, Alpha
Homework Review
The fuel most commonly used in fission
reactions is
(a) Np-239;
(b) U-238;
(c) U-235;
(d) Pu-239.
Homework Review
The fuel most commonly used in fission
reactions is
(a)
(b)
(c) U-235;
(d)
Homework Review
Devices that absorb neutrons and are used
to control the speed of a fission reactor are
called
(a) reactor vessels;
(b) fuel rods;
(c) containment buildings;
(d) control rods.
Homework Review
Devices that absorb neutrons and are used
to control the speed of a fission reactor are
called
(a)
(b)
(c)
(d) control rods.
Homework Review
A fission chain reaction begins when an
atom of U-235 is struck by a neutron.
TRUE or FALSE
Homework Review
A fission chain reaction begins when an
atom of U-235 is struck by a neutron.
TRUE
Homework Review
In a fission reaction, some of the mass of
the original atom is converted to energy.
TRUE or FALSE
Homework Review
In a fission reaction, some of the mass of
the original atom is converted to energy.
TRUE
Homework Review
Each year, an average person in the
United States is exposed to a radiation
level of
(a) 2 rems;
(b) 0.2 rems;
(c) 20 rems;
(d) 200 rems.
Homework Review
Each year, an average person in the
United States is exposed to a radiation
level of
(a)
(b) 0.2 rems;
(c)
(d)
Homework Review
Pu-239 has a half-life of
(a) 24 years;
(b) 240 years;
(c) 2400 years;
(d) 24 000 years.
Homework Review
Pu-239 has a half-life of
(a)
(b)
(c)
(d) 24 000 years.
Homework Review
Losing control of the fission reaction in a
reactor core may result in a
(a) cooldown;
(b) meltdown;
(c) draindown;
(d) cooling tower.
Homework Review
Losing control of the fission reaction in a
reactor core may result in a
(a)
(b) meltdown;
(c)
(d)
Homework Review
The number of people forced to evacuate
because of the Chernobyl accident was
(a) 1,160;
(b) 11,600;
(c) 116,000;
(d) 1,160,000.
Homework Review
The number of people forced to evacuate
because of the Chernobyl accident was
(a)
(b)
(c) 116,000;
(d)
Homework Review
Radon gas is responsible for 25 percent of
the radiation in most U.S. homes.
TRUE or FALSE
Homework Review
Radon gas is responsible for 25 percent of
the radiation in most U.S. homes.
FALSE, 55 percent
Homework Review
Plutonium must be stored for 192,000
years before it is safe.
TRUE or FALSE
Homework Review
Plutonium must be stored for 192,000
years before it is safe.
TRUE
Homework Review
The cleanup of the 20 most polluted
nuclear weapons facilities in the United
States will cost $600 billion.
TRUE or FALSE
Homework Review
The cleanup of the 20 most polluted
nuclear weapons facilities in the United
States will cost $600 billion.
TRUE
Objective Revisited
 Visually
explain how changes in
human societies have changed
the demand for energy
Objective Revisited
 In
a complete sentence describe
the structure of organic fuels
Objective Revisited
 List
the stages of coal formation
and describe the characteristics
of each stage.
Objective Revisited
 Using
the map of the United States
provided for you in you packet
describe to areas where coal
deposits are found. Generalize the
type of coal found and the location.
 Utilize
the next slide to help
clarify colors
PETROLEUM AND NATURAL GAS
•
OBJECTIVES:
•
Describe the processes of petroleum
formation and extraction.
•
List several uses for petroleum and
natural gas.
Objective Revisited
•
In your own words or using
pictures describe the processes
of petroleum formation and
extraction.
Objective Revisited
 Think
back on the uses for
petroleum and natural gas
mentioned in this chapter so far.
List which uses you personally
experience in an average month.
ATOMS AND RADIOACTIVITY
•
OBJECTIVES:
– Describe the structure of the
atom and the atomic nucleus.
– Explain how unstable nuclei
become stable by releasing
radiation.
REACTIONS AND REACTORS
•
OBJECTIVES
– Discuss the fission chain
reactions that power nuclear
reactors
– Diagram the structure and
function of a nuclear reactor.
Objective Revisited
Diagram the structure and
function of a nuclear reactor.
OBJECTIVE REVISITED
Define radioactive waste, explain
the dangers that arise from it and
state the problems involved in the
safe disposal of radioactive
wastes.
OBJECTIVE REVISITED
Write a personal response to
your thoughts about the
Chernobyl accident.
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