Chapter 2 Science, Matter, Energy, and Systems

AP Environmental Miller and Spoolman 19th Ed.

Scientific Theory

A well-tested and widely accepted scientific hypothesis.

Scientific Hypothesis

An educated guess that attempts to explain a scientific law or certain scientific observations.

Positive Feedback Loop

Feedback loop that causes a system to change further in the same direction.

Negative Feedback Loop

Feedback loop that causes a system to change in the opposite direction from which its moving. Maintains a certain range.

Ion

Atom or group of atoms with one or more positive ( ) or negative ( ) electrical charges.

Organic Compounds

Compounds containing more than one carbon atom combined with each other and with atoms of one or more other elements such as hydrogen, oxygen, nitrogen, sulfur, phospho- rus, chlorine, and fluorine. One exception to the more than one carbon rule is Methane CH4

Inorganic Compounds

All compounds not classified as organic compounds.

Energy

Capacity to do work by performing mechanical, physical, chemical, or electrical tasks or to cause a heat transfer between two objects at different temperatures.

Potential Energy

Energy stored in an object because of its position or the position of its parts.

High-Quality Energy

Energy that is concentrated and has great ability to perform useful work and easily accessible.

Low-Quality Energy

Energy that is dispersed and has little ability to do useful work and/or not easily accessible.

First Law of Thermodynamics

In any physical or chemical change, no detectable amount of energy is created or destroyed, but energy can be changed from one form to another; you can- not get more energy out of something than you put in; in terms of energy quantity, you cannot get something for nothing.

Second Law of Thermodynamics

In any conversion of energy to useful work, some of the initial energy input is always degraded

to lower-quality, more dispersed, less useful energy—usually low-temperature heat that flows into the environment; you cannot break even in terms of energy quality.

Energy Efficiency

Percentage of the total energy input that does useful work and is not converted into low-quality, generally useless heat in an energy conversion system or process.

Input

Matter, energy, or information entering a system.

Throughput

Rate of flow of matter, energy, or information through a system.

Output

Matter, energy, or information leaving a system

Acid

A substance with more hydrogen (H+) ions than hydroxide (OH-) ions. pH of less than 7

Base

A substance with more hydroxide (OH-) ions than hydrogen (H+) ions. pH of more than 7

Neutral Substance

pH of 7. Equal parts hydrogen and hydroxide ions.

Tipping Point

This is where something has reached a point where there is a fundamental shift in the behavior of a system. "the point of no return"

Synergy

Occurs when two or more processes interact so that the combined effect is greater than the sum of their separate effects.

Example of closed loop system

The matter on Easter Island

Example of an open loop system

The energy on Easter Island

Add an equal amount of this solution to make a solution, with a pH of 3, neutral.

A solution with pH 11