Science, Matter, and Energy. What is Science? Science is not the body of knowledge that you will...

Science, Matter, and Energy

What is Science?

• Science is not the body of knowledge that you will learn in science classes, nor is it technology or engineering or even medicine.

• Science is an organized way of looking at the world and asking questions; it’s a way of finding out information.

Scientific Method

The actual approach is hypothesis testing.

A hypothesis is an educated guess formulated as a statement that can be disproved.

Three Types of Scientific Methods

• Experimental method involves control and experimental groups and short time spans.

• Comparative method involves looking for natural experiments and testing hypotheses using them.

• Modeling is a simulation of complex processes and systems.

Two Examples of Comparative Method at Work

Examples of ModelingBanana peel model of Titanic sinking

Test of model with computer simulation

Theories and ParadigmsA theory is well-

supported and widely accepted hypothesis that explains a set of interconnected phenomena.

A theory can become a paradigm, an idea or concept so strong that it guides scientists as to what questions they ask.

• Kuhn used the duck-rabbit optical illusion to demonstrate the way in which a paradigm shift could cause one to see the same information in an entirely different way

Scientific Laws

A scientific or natural law is a description of what scientists find happening in nature without exception; a statement of fact about the universe that illustrates something that is always true.

Data

• Scientific data are facts obtained by making observations and measurements.

Things that are science

• Frontier science is that which involves preliminary results; not yet widely accepted by scientists. (life on mars)

• Consensus science involves well-tested, well-supported, and widely accepted results and ideas; mainstream science. (fermentation by yeast, Chlorophyll and photosynthesis )

• Consensus science also reliable science; fringe science might get there (continental

drift).

Things that are not science

• Junk science are ideas that are presented as science, but are not tested and peer reviewed (research on second-hand

smoking).

• Pseudoscience consists of ideas that are presented as science, but are either untestable or completely disproven and are not science (Bermuda Triangle, Bigfoot).

• Both are “unreliable science.”

Chemistry Definitions

• Matter is any substance that has mass and occupies space.

• An element is a pure substance that cannot be broken down into other substances. (an element can have different isotopes)

• Atoms are the smallest particles of an element; they cannot be broken down into smaller particles and still compose that element.

More Definitions• Compounds are substances composed

of two or more elements.• Inorganic compounds do not contain

carbon combined with hydrogen; characteristic of non-living things. (ammonia NH3)

• Organic compounds contain both carbons(at least two) and hydrogen, along with other elements; characteristic of living things. (glucose C6H12O6)

Matter Quality

• Matter quality is a measure of how orderly, concentrated, and useful a material is for humans.

• High-quality matter is very pure and concentrated; very useful.

• Low-quality matter is impure, disordered, and dilute; not useful at all.

Matter Quality at Work (sorting and

recycling)

Physical Changes• physical change alters the state of matter of

a material without changing the composition of a material.

Chemical Changes

• Chemical changes alter the composition; i.e., burning wood gives off water and carbon dioxide, which is not the same as the cellulose and oxygen that was there before. (chemical formula)

Laws of Matter and Energy

• Matter can neither be created nor destroyed; it can merely change form (physical or chemical changes); there is no “away.”

• First law of thermodynamics—energy cannot be created or destroyed, only conserved; you can’t get ahead.

• Second law of thermodynamics--energy is always converted from a higher-quality form into a lower-quality form; entropy—you can’t break even, either.

Matter and PollutionA pollutant is a substance (or energy) in food,

air, water, or soil that impairs the life, health, safety, or even enjoyment of living things, including humans.

Persistence is a measure of how long a pollutant lasts in the environment.-- degradable or non-persistent.-- biodegradable—require the action of living things.-- slowly degradable or persistent—DDT and CFCs as examples.-- nondegradable—plastics, lead, mercury, arsenic.

Energy

• Energy is the ability to do work and transfer heat.

• Kinetic energy is the energy of motion.

• Heat is very low-quality energy and consists of the random motion of molecules.

• Potential energy is energy stored in a system.

Energy Quality

High-quality energy has a high capacity for work.

Low-quality energy has a low capacity for work.

Connection between Laws of Matter and Ecology

• 1. Everything is Connected to Everything Else. There is one ecosphere for all living organisms and what affects one, affects all.

• 2. Everything Must Go Somewhere. There is no "waste" in nature and there is no “away” to which things can be thrown.

• 3. Nature Knows Best. Humankind has fashioned technology to improve upon nature, but such change in a natural system is, says Commoner, “likely to be detrimental to that system.”

• 4. There Is No Such Thing as a Free Lunch. In nature, both sides of the equation must balance, for every gain there is a cost, and all debts are eventually paid.

High Throughput Economy

Recycling Economies

• Matter-recycling and reuse economies still have high throughput, but reduce waste by re-using and recycling high-quality matter and energy.

• Low-throughput economies not only reduce waste, but reduce the inputs as well—much more recycling and reuse of low-quality as well as high-quality materials.

The choice is up to you.

An Example of Modeling