Chapter 7 Section 2
II Nonrenewable Energy
- nonrenewable resources – a resource that forms at a rate that
is much slower than the rate at which it is consumed
A. Fossil Fuels
- most nonrenewable resources are buried beneath
Earth’s surface
- fossil fuels – a nonrenewable energy resource that
formed from the remains of organisms that lived
long ago; examples include oil, coal and natural gas
- hydrocarbons – compounds of hydrogen and carbon
1. Formation of Coal
a. most commonly burned fossil fuel
b. remains of plants that have undergone
carbonization
c. carbonization
1c. partially decomposed plant material is buried
swamp mud and becomes peat
2c. bacteria consume the peat and release CH4
and CO2
3c. coal only forms if oxygen is absent
2. Types of Coal Deposits
a. lignite
1a. formed when pressure above the peat forces
water out
2a. becomes a much denser material
b. bituminous coal
1b. increased temperature and pressure
compacts the lignite
2b. most abundant type of coal
c. anthracite
1c. formed by high temperatures and pressure
2c. hardest form of coal
3. Formation of Petroleum and Natural Gas
a. intense pressure and heat turn the remains of
once living organisms into petroleum
b. occurs over millions of years
c. petroleum and natural gas are mixtures of
hydrocarbons
c. oil – petroleum made of liquid hydrocarbons
d. natural gas is hydrocarbons in the form of gas
4. Petroleum and Natural Gas Deposits
a. mined from permeable rock – interconnecting
spaces through which liquids can easily flow
b. increase pressure forces fluids up through the
layers of permeable rock
c. they continue upward until they reach a layer
of impermeable rock – rock through which
liquids cannot flow called cap rock
d. petroleum that accumulates beneath the cap rock
fills all spaces to form an oil reservoir
5. Oil Traps
a. geologists explore Earth’s crust to discover
the kinds of rock structures that may trap
oil or gas
b. when an oil well is drilled, the petroleum and
and natural gas often flow to the surface
B. Fossil-Fuel Supplies
1. fossil fuels are nonrenewable
2. crude oil
a. unrefined petroleum
b. used in the production of plastics, synthetic
fabrics, medicines, waxes, synthetic rubber,
insecticides, chemical fertilizers, detergents,
shampoos and many other products
3. coal is the most abundant fossil fuel in the world
C. Nuclear Energy
- nuclear energy – energy that is produced by using
nuclear technologies
1. nuclear fission – the process by which the nucleus
of a heavy atom splits into two or more
fragments; the process releases neutrons and energy
a. the forces that hold the nucleus together are 1
million times stronger than the strongest chemical
bond
b. when the nucleus splits, caused by bombarding
the nucleus with neutrons, it releases additional
neutrons and energy
c. newly released neutrons strike additional atoms
and the process continues until there are no more
atoms to split (chain reaction)
d. if fission is not controlled, it may result in an
explosion
e. controlled fission produces heat that can be used
to generate electricity
2. How Fission Generates Electricity
a. nuclear fission is controlled
b. nuclear reactor – specialized equipment in which
controlled nuclear fission is carried out
c. the tremendous amount of energy released is used
convert water into steam to turn a turbine in turn
to produce electricity
d. Uranium-235
1d. only naturally occurring element that is used
2d. ore is mined and processed into fuel pellets
3d. the pellets are then placed into fuel rods
4d. fuel rods are exposed to neutrons to begin the
process and will continue be controlled to
produce heat which will eventually become
electricity
3. Advantages and Disadvantages of Nuclear Fission
a. nuclear power plants burn no fossil fuels and
produce no air pollution
b. nuclear wastes must be stored safely for
thousands of years because of the long half-life
of some of the nuclear waste
c. nuclear waste gives off radiation that can be
harmful to plant and animal cells
d. nuclear waste is stored in dry casks or in
onsite water pools
4. Nuclear Fusion
a. the process by which nuclei of small atoms
combine to form new, more massive nuclei;
this process releases energy
b. two hydrogen nuclei combine to produce a
single helium nuclei
c. this process only occurs at a temperatures of
over 15 000 000 oC
d. if the process becomes available, then hydrogen
would come from ocean water
e. waste would be less dangerous than fission
f. helium atoms are harmless to plant and animal
cells