Transcript APES Ch. 3 Notes

APES Ch. 3 Notes
Science, Systems, Matter, and Energy
IX. Matter: Forms,
Structure and Quality
Matter – anything that has
mass and takes up space.
Calcite
mixture
Gold (Au)
(CaCO3)
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.
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
Energy absorbed
solid
Melting
Evaporation
And boiling
Freezing
Condensation
liquid
Energy released
gas
Fig. 3.5, p. 54
Components of Atoms
a. 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 – total
number of protons in an
atom
Atomic Mass – total number
of protons and neutrons in
an atom
Mass #
4
Atomic #
2
He
Hydrogen (H)
0n
1p
1n
1p
1e
Mass number = 0 + 1 = 1
Hydrogen-1
(99.98%)
2n
1p
1e
Mass number = 1 + 1 = 2
Hydrogen-2
or deuterium
(0.015%)
1e
Mass number = 2 + 1 = 3
Hydrogen-3
or tritium (T)
(trace)
Uranium (U)
143 n
92 p
Mass number = 143 + 92 = 235
Uranium-235
(0.7%)
92e
146
143 n
92 p
92e
Mass number = 146 + 92 = 238
Uranium-238
(99.3%)
Atomic Number – total number of protons it an atom
Atomic Mass – total number of protons and neutrons in an atom
Fig. 3.6, p. 55
PH – (pH) – measure of the concentration of
hydrogen ions [H+] in a water solution.
Concentration=.001 = 10-3 = pH = 3
Fig. 3.7, p. 56
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
g.
NO2
b.
H2O
h.
SO2
c.
N2O
i.
NH3
d.
NO
j.
H2S
e.
CO
k.
H2SO4
f.
CO2
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.
High Quality
Low Quality
Solid
Gas
Salt
Solution of salt in water
Coal
Coal-fired power
plant emissions
Gasoline
Automobile emissions
Fig. 3.9, p. 57
Aluminum can
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.
b.
c.
d.
e.
f.
g.
Wind
Flowing Streams
Heat (flowing from high to low)
Electricity
Electromagnetic Radiation
Heat (total kinetic energy of all the moving atoms, ions,
or molecules within a given substance)
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.
Energy
Two Laws of
• 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
(photosynthesis)
Waste
heat
Mechanical
energy
Chemical
energy
(food)
Chemical
energy
Solar
energy
Waste
heat
(moving,
thinking,
living)
Waste
heat
Waste
heat
Fig. 3.18, p. 66
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
Sun
High energy, short
wavelength
Low energy, long
wavelength
Nonionizing radiation
Ionizing radiation
Cosmic
rays
Gamma
rays
10-14
X rays
10-12
Visible
Far
Near
ultraviolet ultraviolet waves
waves
waves
10-8
10-7
10-6
Near
infrared
waves
10-5
Far
infrared
waves
microwaves
10-3
TV
waves
10-2 10-1
Radio
waves
1
Wavelength
in meters
(not to scale)
Fig. 3.10, p. 58
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.
Electricity
Very high temperature
heat (greater than 2,500°C)
Nuclear fission (uranium)
Nuclear fusion (deuterium)
Concentrated sunlight
High-velocity wind
High-temperature heat
(1,000–2,500°C)
Hydrogen gas
Natural gas
Gasoline
Coal
Food
Normal sunlight
Moderate-velocity wind
High-velocity water flow
Concentrated
geothermal energy
Moderate-temperature heat
(100–1,000°C)
Wood and crop wastes
Dispersed geothermal energy
Low-temperature heat
(100°C or lower)
Source of Energy
Very high
Very high-temperature heat
(greater than 2,500°C)
for industrial processes
and producing electricity to
run electrical devices
(lights, motors)
High
Mechanical motion (to move
vehicles and other things)
High-temperature heat
(1,000–2,500°C) for
industrial processes and
producing electricity
Moderate
Moderate-temperature heat
(100–1,000°C) for industrial
processes, cooking,
producing steam,
electricity, and hot water
Low
Relative Energy Quality
(usefulness)
Low-temperature heat
(100°C or less) for
space heating
Energy tasks
Fig. 3.11, p. 59
• 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
Sheet
of paper
Block
of wood
Concrete
wall
Alpha
Beta
Gamma
Fig. 3.12, p. 62
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)
Fraction of original amount of
plutonium-239 left
1
1/2
1/4
1/8
1st
half-life
2nd
half-life
3rd
half-life
0
240,000
480,000
Time (years)
720,000
Fig. 3.13, p. 62
Other
1%
Consumer
products
3%
Radon
55%
Nuclear
medicine
4%
Medical
X rays
10%
Natural sources 82%
Human-generated 18%
Space
8%
The
human
body
11%
Earth
8%
Fig. 3.14, p. 63
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)
Fission fragment
n
n
n
Energy
n
Uranium-235
nucleus
Unstable
nucleus
Fission fragment
Fig. 3.15, p. 64
235
92 U
n
92
36 Kr
n
235
92 U
92
36 Kr
235
92 U
n
n
141
Ba
56
n
92 Kr
36
n
n
n
n
235
92 U
n
141
56 Ba
141
Ba
56
92 Kr
n
36
235
92 U
n
141
Ba
56
235
92 U
n
235
92 U
Fig. 3.16, p. 64
Fuel
Reaction Conditions
Products
D-T Fusion
Neutron
+
Hydrogen-2 or
deuterium nucleus
+
+
+
100 million ˚C
Energy
+
+
Helium-4
nucleus
Hydrogen-3 or
tritium nucleus
D-D Fusion
+
+
+
Helium-3
nucleus
Hydrogen-2 or
deuterium nucleus
+
+
Energy
+
+
Proton
Neutron
Hydrogen-2 or
deuterium nucleus
1 billion ˚C
Neutron
Fig. 3.17, p. 64