Chapter 2: Properties of Matter

Matter

anything that occupies space and has mass

Mass

measure of the amount of matter an object has

Atom

the smallest particle that can contain the chemical properties of an element

Element

a substance composed of atoms that cannot be broken down into smaller, simpler component

Molecules

particles containing more than one atom

Compounds

molecules that contain more than one element

Atomic Number

the number of protons in the nucleus of a particular element, unique to that element

Mass Number

the total number of protons and neutrons in an element

Isotopes

atoms of the same element with different numbers of neutrons

Radioactive Decay

the spontaneous release of material from the nucleus

Half Life

the time it takes for one-half of the original radioactive parent atoms to decay

Covalent Bond

when hydrogen atoms bond to the oxygen atom by sharing electron pairs

Ionic Bond

a chemical bond between 2 oppositely charged ions

Hydrogen Bond

a weak chemical bond that forms when hydrogen atoms that are covalently bonded to one atom are attracted to another atom on another molecule

Polar Molecule

a molecule in which one side is more positive and the other side is more negative

Energy

the ability to do work or transfer heat

Electromagnetic Radiation

a form of energy emitted by the sun that includes, but is not limited to, visible light, ultraviolet light, and infrared energy

Photon

a massless packet of energy that carries electromagnetic radiation at the speed of light

Joule

the amount of energy used when a one-watt electrical device is turned on for one second

Potential Energy

stored energy that has not been released

Kinetic Energy

the energy of motion

Chemical Energy

potential energy stored in chemical bonds

Temperature

the measure of the average kinetic energy of a substance

First Law of Thermodynamics

a law of nature stating that energy can neither be created nor destroyed

Second Law of Thermodynamics

the law stating that when energy is transformed, the quantity of energy remains the same, but its ability to do work diminishes

Energy Efficiency

the ratio of the amount of work done to the total amount of energy introduced to the system

Energy Quality

the ease with which an energy source can be used for work

Entropy

randomness in a system

Open System

a system in which exchanges of matter or energy occur across system boundaries

Closed System

a system in which matter and energy exchanges do not occur across boundaries

Outputs

a loss from a system

Inputs

an addition to a system

Systems Analysis

an analysis to determine inputs, outputs, and changes in a system under various conditions

Steady State

a state in which inputs equal outputs, so that the system is not changing over time

Feedback

an adjustment in input or output rates caused by changes to a system

Negative Feedback Loops

a feedback loop in which a system responds to a change by returning to its original state, or by decreasing the rate at which the change is occurring

Positive Feedback Loop

a feedback loop in which change in a system is amplified

Adaptive Management Plans

a plan that provides flexibility so that managers can modify it as changes occur

Solvent

usually a liquid and is the more abundant component

Solute

often a solid or gas, less abundant

Acid

a substance that contributes hydrogen ions to a solution, above 7 pH

Base

a substance that contributes hydroxide ions to a solution, below 7 pH

Inorganic Compounds

do not contain carbon, but only carbon bound to elements other than hydrogen

Organic Compounds

have carbon-carbon and carbon-hydrogen bonds and hydrogen-oxygen