Chapter 2
Science, Systems,
Matter, and Energy
Core Case Study:
Environmental Lesson from Easter
Island
 Thriving

society
15,000 people by 1400.
 Used
resources faster
than could be renewed

By 1600 only a few
trees remained.
 Civilization

collapsed
By 1722 only several
hundred people left.
Figure 2-1
TYPES AND STRUCTURE OF
MATTER
 Elements

and Compounds
Matter exists in chemical forms as elements and
compounds.
• Elements (represented on the periodic table) are the
distinctive building blocks of matter.
• Compounds: two or more different elements held
together in fixed proportions by chemical bonds.
Atoms
Figure 2-4
Ions
 An
ion is an atom or group of atoms with one
or more net positive or negative electrical
charges.
 The number of positive or negative charges
on an ion is shown as a superscript after the
symbol for an atom or group of atoms


Hydrogen ions (H+), Hydroxide ions (OH-)
Sodium ions (Na+), Chloride ions (Cl-)
 The
pH (potential of Hydrogen) is the
concentration of hydrogen ions in one liter of
solution.
Figure 2-5
Organic Compounds: Carbon Rules
 Organic
compounds contain carbon atoms
combined with one another and with various
other atoms such as H+, N+, or Cl-.
 Contain at least two carbon atoms combined
with each other and with atoms.


Methane (CH4) is the only exception.
All other compounds are inorganic.
Organic Compounds: Carbon Rules
 Hydrocarbons:
compounds of carbon and
hydrogen atoms (e.g. methane (CH4)).
 Chlorinated hydrocarbons: compounds of
carbon, hydrogen, and chlorine atoms (e.g.
DDT (C14H9Cl5)).
 Simple carbohydrates: certain types of
compounds of carbon, hydrogen, and oxygen
(e.g. glucose (C6H12O6)).
Cells: The Fundamental Units of Life
 Cells
are the basic
structural and
functional units of all
forms of life.


Prokaryotic cells
(bacteria) lack a distinct
nucleus.
Eukaryotic cells (plants
and animals) have a
distinct nucleus.
Figure 2-6
Matter Quality
 Matter
can be classified
as having high or low
quality depending on
how useful it is to us as
a resource.


High quality matter is
concentrated and easily
extracted.
low quality matter is more
widely dispersed and
more difficult to extract.
Figure 2-8
CHANGES IN MATTER
 Matter
can change from one physical form to
another or change its chemical composition.

When a physical or chemical change occurs, no
atoms are created or destroyed.
• Law of conservation of matter.


Physical change maintains original chemical
composition.
Chemical change involves a chemical reaction
which changes the arrangement of the elements
or compounds involved.
• Chemical equations are used to represent the
reaction.
Types of Pollutants
 Factors
that determine the severity of a
pollutant’s effects: chemical nature,
concentration, and persistence.
 Pollutants are classified based on their
persistence:




Degradable pollutants
Biodegradable pollutants
Slowly degradable pollutants
Nondegradable pollutants
Nuclear Changes: Radioactive Decay
 Natural
radioactive decay: unstable isotopes
spontaneously emit fast moving chunks of
matter (alpha or beta particles), high-energy
radiation (gamma rays), or both at a fixed
rate.


Radiation is commonly used in energy production
and medical applications.
The rate of decay is expressed as a half-life (the
time needed for one-half of the nuclei to decay to
form a different isotope).
Nuclear Changes: Fission
 Nuclear
fission:
nuclei of certain
isotopes with large
mass numbers are
split apart into
lighter nuclei when
struck by neutrons.
Figure 2-9
Nuclear Changes: Fusion
 Nuclear
fusion: two isotopes of light elements
are forced together at extremely high
temperatures until they fuse to form a heavier
nucleus.
Figure 2-10
Source of Energy
Electricity
Very high temperature heat
(greater than 2,500°C)
Nuclear fission (uranium)
Nuclear fusion (deuterium)
Concentrated sunlight
High-velocity wind
Relative
Energy Tasks
Energy Quality
(usefulness)
Very high-temperature heat
(greater than 2,500°C) for
industrial processes and
producing electricity to run
electrical devices (lights,
motors)
High-temperature heat
(1,000–2,500°C)
Hydrogen gas
Natural gas
Gasoline
Coal
Food
Mechanical motion to move
vehicles and other things)
High-temperature heat
(1,000–2,500°C) for
industrial processes and
producing electricity
Normal sunlight
Moderate-velocity wind
High-velocity water flow
Concentrated geothermal energy
Moderate-temperature heat
(100–1,000°C)
Wood and crop wastes
Moderate-temperature heat
(100–1,000°C) for
industrial processes, cooking,
producing
steam, electricity, and
hot water
Dispersed geothermal energy
Low-temperature heat
(100°C or lower)
Low-temperature heat
(100°C or less) for
space heating
Fig. 2-13, p. 44
ENERGY LAWS: TWO RULES WE
CANNOT BREAK
 The
first law of thermodynamics: we cannot
create or destroy energy.

We can change energy from one form to another.
 The
second law of thermodynamics: energy
quality always decreases.


When energy changes from one form to another,
it is always degraded to a more dispersed form.
Energy efficiency is a measure of how much
useful work is accomplished before it changes to
its next form.
SUSTAINABILITY AND MATTER
AND ENERGY LAWS
 Unsustainable
High-Throughput Economies:
Working in Straight Lines

Converts resources to goods in a manner that
promotes waste and pollution.
Figure 2-15
Sustainable Low-Throughput
Economies: Learning from Nature
 Matter-Recycling-and-Reuse
Economies:
Working in Circles


Mimics nature by recycling and reusing, thus
reducing pollutants and waste.
It is not sustainable for growing populations.