All terms in this list:

Molecule: a group of two or more atoms held together by chemical bonds

Pure Substance: Matter that has the same chemical composition throughout and cannot be separated into it's parts bu physical means

Homogeneous Mixture: A mixture in which substances are evenly distributed

Heterogeneous Mixture: A mixture in which substances are not distributed evenly

Element: One of the basic substances that come to form all other substances.Substance that cannot be broken down into simpler substances by ordinary means

Atom: The basic building block of most of the matter around us,the smallest particle of an element that has all the properties of an element

Compound: A substance formed from the chemical combination of two or more elements

Physical Property: A characteristic of a substance that can be observed directly or measured with a tool without changing the identity of the substance
ex:Color,Texture,Solubility,Density

Physical Change: A change in a substance that does not change the chemical makeup of the substance
ex:cutting grass,banana turning from green to yellow

Chemical Property: A characteristic of a substance that cannot be observed without changing the identity of the substance
Ex:Burned paper,Cooked eggs,Exploded Fireworks,Rusted Nail

Chemical Change: A change that results in the formation of a new substance or substances
Ex:Ash,Mold,Radiation,Rust

Precipitate: A solid that forms during a chemical reaction that takes place in a solution

Solubility: The ability of one substance to dissolve into another.The amount of the solute that can dissolve in a particular substance

Groups: A vertical column in the periodic table also called the chemical family

Periods: A horizontal row in the periodic table

Metals: An element that conducts heat and electricity well,is shiny and can be hammered into sheet or drawn into wires

Nonmetals: An element that does not conduct heat or electricity well and is dull and brittle or gaseous

Metalloids: An element that has some properties of both metals and nonmetals

Protons: A positively charged particle found in the nucleus of an atom

Electrons: A negatively charged substance particle that is located outside the nucleus of an atom

Neutron: A particle with no charge,found in the nucleus of an atom

Atomic number: The number of protons in the nucleus

Atomic Mass: A measure of an atoms mass that is equal to the number of protons and neutrons in the atoms nucleus

Coefficient: A number written before a chemical formula to show how many atoms or molecules of that substance are involved in a reaction

Subscript: A number that tells how many atoms of each element are in a molecule,Written below and after the element it refers to.Number of for each element

Reactant: A substance that is present at the beginning of a chemical reaction

Product: A substance that is produced during a chemical reaction

Closed System: When chemicals are reacted in a closed container there not exposed to air or oxygen

Laws OF Conversation OF Mass: The scientific principle that matter is neither created nor destroyed during a chemical change

Permeable: Having pores or openings that allow water or other liquids to flow through
Ex:Sand,Dirt,and/or Rock

Clean Water Act: The primary federal law in the United States governing water pollution

Point Source Pollution: Water pollution comes from a known and specific location
Ex:Pipes,labeled barrels leaking oil

Non Point Source Pollution: Water pollution that does not have a specific point of origin
Ex:Trash on the road

Turbidity: A measure of clarity or clearness of water
Ex:high turbidity is murky,Low is clear

Upwelling: The rising of cold water from deeper layers to replace warmer surface water that has been moved away,Nutrients from the bottom go to the top

Tributaries: A stream that empties itself into another stream

Surface Water: The water on the surface of the planet such as in streams,rivers,lakes,or oceans

Wetlands: Areas of land that are covered with a shallow layer of water for at least part of the year
Ex:Bogs,Marshes,Swamps,Poor drainage

Safe Water Act: The main federal law that ensures the quality of Americans drinking water

Potable Water: A measure of the activity of the hydrogen and is reported as the reciprocal of the logarithm of the hydrogen ion activity

Subsidence: Sinking cause when an aquifer compacts and the surface of ground sinks with it

Biological Indicator: Used to monitor the health of an ecosystem some of these organisms survive only under specific conditions
Ex:trout-healthy water,Black fly larvae-unhealthy water

Chemosynthesis: The process by which some organisms use the energy stored in chemical bonds to make their own food

Thermal Pollution: Pollution caused by excess heat being released into the enviornment

Urban Development: The growth of a city over a large area in an unplanned manner

Estuary: Bodies of water where a river meets the oceans,Also referred to as salt marshes,bays,harbors,inlets,and sounds

Impermeable: Describes rocks that do not allow water through them

Runoff: Water that is not absorbed by soil or rocks and flows downhill

Aquifers: Porous underground layers of rock that can store large amounts of water

River Basin: The land that water flows across or under on it's way to a river

Watershed: The area drained by a river system

Ground Water: Water underground in the zone of saturation

Infiltration: When water seeps into and between particles of soil

Porosity: The volume of open spaces in rock or soil
Ex:Sand,Rocks,and Dirt

Warm Front: A front along which a warm air mass overrides a retreating mass of cooler air

Stationary Front: A situation in which the surface position of a front does not move,the flow on either side of such a boundary is nearly parallel to the position of the front
Ex:Clouds,Rain,Icy Weather

Relative Humidity: The ratio of the airs water vapor content to it's water vapor capacity

Radiation: The transfer of energy (heat) through space by electromagnetic waves

Convection: The transfer of heat by the movement of a mass or substance;It can take place only in fluids

Conduction: The transfer of heat through matter by molecule activity;Energy is transferred through collisions from one molecule to another

Anemometer: A instrument used to determine wind speed

Cold Front: A front along which a cold air mass thrusts beneath a warmer air mass
Ex:clouds,Showers,Thunderstorms

Dewpoint: The temperature to which air has to be cooled in order to reach saturation

Front: The boundary between two adjoining air masses having contrasting characteristics

Occluded Front: A front formed when a cold front overtakes a warm front.It marks the beginning of the end of a middle-latitude cyclone
Ex:Cyclone,Tornado,Precipitation

Air Mass: A large body of air that is characterized by similar temperatures and amounts of moisture at any given altitude

Air Pressure: The force exerted by the weight of a column of air above a given point

Weather: The day to day conditions of a particular place and time
Ex:Severe thunderstorm,Skies are clearing

Climate: The average weather conditions of a place over a long period of time
Ex:Typically rainfall in June will be under 1 inch

Green House Effect: The heating of Earth's surface and atmosphere from solar radiation being absorbed and emitted by the atmosphere,mainly by water vapor,and carbon dioxide

ElNino: The name given to the periodic warming of the ocean that occurs in central and eastern Pacific.A major ElNino can course extreme weather

Koppen Climate Classification System: A system for classifying climates that is based on mean monthly and annual values of temperatures and precipiataion

Fossil Fuels: A general term for any hydrocarbon that may be used as fuel,including coal,oil,and natural

Global Warming: The increase in average temperatures of the earth and the atmosphere due in part to increased carbon dioxide levels

Igneous Rock: Rock formed by the crystallization of molten magma
Ex:Intrusive formed below the surface,Extrusive formed near of under the surface

Sedimentary Rock: Rock formed from the weathered products of preexisting rock that have been transported,compacted,and cemented

Metamorphic Rock: Rock formed by the alteration of preexisting rock deep within earth by heat,pressure,and/or chemically active fluids

Epicenter: The point directly above the focus

Focus: Point within Earth where an Earthquake starts

Bedding: Arrangement of sedimentary rock

Deposition: The process by which an agent of erosion loses energy and drops the sediment it is carrying

Physical(mechanincal)Weathering: The physical disintegration of rock,resulting in smaller fragments

Chemical Weathering: The process by which the internal structure of a mineral is altered by the removal and/or addition of elements