Transcript Second law of thermodynamics

Chapter 2
Environmental Systems
Earth is a single
interconnected
system
All environmental
systems consist of matter
What are the basic
building blocks of
matter?
All environmental systems consist of
matter
Molecules (O2)
Compound (CO2)
Fig. 2-4a, p. 38
Table 2-1, p. 38
Atoms, Ions, and Molecules Are the
Building Blocks of Matter
• Atomic theory
•All elements are made of atoms
• Subatomic particles
• Atomic number
Model of a Carbon12 Atom
• Mass number
•Isotopes
Fig. 2-5, p. 39
Table 2-2, p. 40
Matter Undergoes Physical,
Chemical, and Nuclear Changes
• Nuclear change
•What is created?
• Half-life
•Why is this important to know?
Fig. 2-9, p. 43
Chemical bonds
Properties of water
Properties of water
Properties of water
pH Scale
• pH
• Measure of acidity
• H+ and OH-
Supplement 5, Figure 4
Matter Undergoes Physical,
Chemical, and Nuclear Changes
• Physical change
• Chemical change, chemical reaction
• Law of Conservation of Matter
Organic Compounds Are the
Chemicals of Life
• Inorganic compounds
•
only carbon bound to elements other than hydrogen.
• ex. NH3, NaCl, H2O, and CO2
• Organic compounds
• have carbon-carbon and carbon-hydrogen bonds
Supplement 4, Fig. 9
DNA Double Helix Structure and Bonding
Supplement 4, Fig. 10
Amino Acids and Proteins
Supplement 4, Fig. 8
Glucose Structure
Supplement 4, Fig. 4
Fatty Acid Structure and Trigyceride
Supplement 4, Fig. 11
Matter Comes to Life
through Genes,
Chromosomes, and Cells
• The basic building blocks of
LIFE
• Cells
• Chromosomes
• Genes
Fig. 2-7, p. 42
Forms of Energy
Forms of Energy
• Energy = power X time
• Power = energy/time
• Joule = 1 watt x sec
First law of thermodynamics
• You can’t get something from nothing.
Second law of thermodynamics
•
When energy is transformed, the quantity of
energy remains the same, but its ability to do
work diminishes.
Figure 2.15
Second law of thermodynamics
• Some systems are more energy efficient than others.
• Some forms of energy are higher
quality than others.
Figure 2.14
Second law of thermodynamics
• All systems move toward randomness rather than
toward order.
• This randomness is always increasing in a
system, unless new energy from the outside of
the system is added to create order.
The amount of available energy determines which
organisms can live in a natural system
Abundant energy
Depend on marine snow
Very little energy
Depend on chemosynthesis
System analysis shows how matter
and energy flow in the environment
Steady states
• System is still dynamic
• System is at equilibrium
Feedbacks
• Negative, or corrective,
feedback loop
• Positive feedback loop
• Tipping point, threshold level
To what extent is Earth’s temperature
regulated by feedback loops?
• Warmer temperatures at Earth’s surface increase
evaporation of water
• Additional water vapor results in cloud formation
Result: absorb
more terrestrial
energy, higher
surface temps,
more
evaporation,
more warming
NEGATIVE
POSITIVE
Result: less
heating of
surface, less
evaporation,
less warming
System Effects Can Be Amplified
through Synergy
• Synergistic interaction, synergy
• Two or more processes combine in such a way that
combined effect is greater than the two separate
effects
• Helpful
• Studying with a partner
• Harmful
• E.g., Smoking and inhaling asbestos particles
Managing Environmental Systems
in the Florida Everglades
Three key steps: increase water flow, reduce pollutants
coming in, develop strategies for dealing with future
problems