Unit 1 Powerpoint Review for Chapter 2

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Unit 1 PowerpointReview for Chapter 2
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What Is Science?

• Science is a pursuit of knowledge about how the
  world works
• Scientific data is collected by making
  observations and taking measurements
• Observations involve the five senses, and help
  answer questions or problems

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Observation

• Qualitative
• of, relating to, or involving quality or kind
• ie. red, hot, burns quickly, etc.
• Quantitative
• of, relating to, or involving the measurement of
  quantity or amount
• ie. 350 degrees Celsius, 5 inches, etc.

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Vocabulary

• Experiment
• A procedure to study a phenomenon under known
  conditions
• Must have a Control
• Hypotheses
• A possible explanation of something observed in
  nature.
• Model
• An approximate representation of a system being
  studied.

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Theory and Law

• Scientific Theory
• A hypothesis that has been supported by multiple
  scientists experiments in multiple locations
• A Scientific Law
• a description of what we find happening in nature
  over and over again in a certain way

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Scientific Laws

• Law of Conservation of Matter
• Matter can be changed from one form to another,
  but never created or destroyed.
• Atomic Theory of Matter
• All matter is made of atoms which cannot be
  destroyed, created, or subdivided.

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Accuracy and Precision

• Accuracy
• The extent to which a measurement agrees with the
  accepted or correct value for that quantity.
• Precision
• A measure of reproducibility, or how closely a
  series of measurements of the same quantity
  agrees with one another.

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Reasoning

• Inductive Reasoning
• Uses observations and facts to arrive at
  hypotheses
• All mammals breathe oxygen.
• Deductive Reasoning
• Uses logic to arrive at a specific conclusion
  based on a generalization
• All birds have feathers, Eagles are birds,
  therefore All eagles have feathers.

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Scientific Methods

• What is the question to be answered?
• What relevant facts and data are known?
• What new data should be collected?
• After collection, can it be used to make a law?
• What hypothesis can be invented to explain this?
  How can it become a theory?

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Experiments

• Variables are what affect processes in the
  experiment.
• Controlled experiments have only one variable
• Experimental group gets the variable
• Control group does not have the variable
• Placebo is a harmless pill that resembles the
  pill being tested.
• In double blind experiments, neither the patient
  nor the doctors know who is the control or
  experiment group.

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Systems

• A system is a set of components that function and
  interact in some regular and predictable manner
• Human body, a river, an economy, The Earth!
• The earth is a closed system for matter and
  an open system for energy

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Feedback Loops

• A feedback loop occurs when an output of a system
  is fed back as an input (two kinds)
• Positive loops are runaway cycles where a change
  in a certain direction causes further change in
  the same direction
• Negative loops occur when a change in a certain
  direction leads to a lessening of that change

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Resource Consumption and Environmental Problems

• Underconsumption
• Overconsumption
• Affluenza unsustainable addiction to
  overconsumption and materialism.

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• The pH (potential of Hydrogen) is the
  concentration of hydrogen ions in one liter of
  solution.

Figure 2-5
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Compounds and Chemical Formulas

• Chemical formulas are shorthand ways to show the
  atoms and ions in a chemical compound.
• Combining Hydrogen ions (H) and Hydroxide ions
  (OH-) makes the compound H2O (dihydrogen oxide,
  a.k.a. water).
• Combining Sodium ions (Na) and Chloride ions
  (Cl-) makes the compound NaCl (sodium chloride
  a.k.a. salt).

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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
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Macromolecules, DNA, Genes and Chromosomes

• Large, complex organic molecules (macromolecules)
  make up the basic molecular units found in living
  organisms.
• Complex carbohydrates
• Proteins
• Nucleic acids
• Lipids

Figure 2-7
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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
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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.

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Chemical Change

• Energy is given off during the reaction as a
  product.

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ENERGY

• Energy is the ability to do work and transfer
  heat.
• Kinetic energy energy in motion
• heat, electromagnetic radiation
• Potential energy stored for possible use
• batteries, glucose molecules

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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.

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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.