science, systems, matter, and energy. matter: forms, structure, and quality matter is anything that...
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Matter: Forms, Structure, and QualityMatter is anything that has mass and takes
up space. It is found in two chemical forms:Elements—Distinctive building blocks of matterCompounds—Two or more different elements
held together by chemical bonds
Various elements, compounds, or both can be found together in Mixtures.
Atoms—the smallest unit of an element
Ions—electrically charged atoms or combinations of atoms
Molecules—combinations of two or more atoms held together by chemical bonds.
Organic and Inorganic CompoundsOrganic compounds contain carbon combined
with one or more other element.Organic Pollutants:
Hydrocarbons—fossil fuels DDT-insecticide CFCs-aerosol propellant that destroys ozone
Inorganic compounds do not contain carbon.
Four States of MatterThree physical states
Solid
Liquid
Gas
Fourth state called Plasma—A high energy mixture of charged ions.
Matter QualityHigh-Quality Matter—concentrated, found
near the earth’s surface, great potential as a resource.
Low-Quality Matter—dilute, found underground, beneath the ocean, or in the atmosphere, little potential as a resource.
Material EfficiencyThe total amount of material needed to
produce each unit of goods or services.Only about 2-6 percent of the matter
resources flowing through the economies of developed countries ends up providing useful goods and services because of waste.
Energy: Forms and Quality
Kinetic Energy—energy in motion—wind, flowing streams, electricity.
Potential Energy—Stored Energy—water behind a dam, unlit stick of dynamite, gasoline.
Electromagnetic RadiationThe electromagnetic spectrum is the range of
electromagnetic wavelengths from long (radio waves) to short (cosmic rays)
How Heat is TransferredConvection: The transfer of heat by the
movement of heated material—through the atmosphere.
Conduction: The transfer of heat by collisions of atoms or molecules—through metal.
Radiation: The transfer of heat by wave motion—through space.
Physical and Chemical ChangesPhysical Change—no change in chemical
composition-cutting paper.
Chemical Change—change in chemical composition—frying an egg
Law of Conservation of MatterMatter cannot ever be created or destroyed,
it can only change forms. Therefore, everything we think we throw away is still here in some form.
How Harmful are Pollutants?Three factors:
Chemical nature
Concentration—How much is there?
Persistence—How long will it stay in the air, water, etc?
3-1 Science and Critical ThinkingScience is an attempt to discover order in
nature and use that knowledge to make predictions about what is likely to happen in nature.
Scientific or Natural Law is a discription of what we find happening over and over in the same way.
Inductive Reasoning involves using specific observations and measurements to arrive at a general conclusion or hypothesis
Deductive Reasoning involves using logic to arrive at a specific conclusion based on a generalization.
Scientists do two major things:Disprove thingsEstablish that a particular model, theory, or
law has a very high probability of being true
Models and Behavior of SystemsMost systems have the following key
components:Inputs—go into the system (energy,
information)Flows or Throughputs—goes through the
systemStores—accumulates for a length of timeOutputs—moves out of the system (matter,
energy, information)
Feedback LoopsOccurs when an output of matter, energy, or
information is fed back into a system and changes it.Positive Feedback Loop—Changes further in
the same direction.Negative Feedback Loop—Changes in the
opposite direction.Most systems have a combination of positive
and negative feedback loops.
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