Apologia Physical Science Terms Modules 1-8

Front 1

atom

Back 1

The smallest stable unit of matter in Creation

Front 2

molecule

Back 2

Two or more atoms linked together to make a substance with unique properties

Front 3

concentration

Back 3

The quantity of a substance within a certain volume of space

Front 4

humidity

Back 4

The moisture content of air

Front 5

absolute humidity

Back 5

The mass of water vapor contained in a certain volume of air

Front 6

relative humidity

Back 6

A quantity expressing humidity as a percentage of the maximum absolute humidity for that particular temperature

Front 7

greenhouse effect

Back 7

The process by which certain gases (principally water vapor, carbon dioxide, and methane) trap heat that would otherwise escape the earth and radiate into space

Front 8

parts per million

Back 8

The number of molecules (or atoms) of a substance in a mixture for every one million molecules (or atoms) in that mixture

Front 9

atmosphere

Back 9

The mass of air surrounding a planet

Front 10

atmospheric pressure

Back 10

The pressure exerted by the atmosphere on all objects within it

Front 11

barometer

Back 11

An instrument used to measure atmospheric pressure

Front 12

homosphere

Back 12

The lower layer of earth's atmosphere, which exists from ground level to roughly 80 kilometers (50 miles) above sea level

Front 13

heterosphere

Back 13

The upper layer of earth's atmosphere, which exists higher than 80 kilometers (50 miles) above sea level

Front 14

troposphere

Back 14

The region of the atmosphere that extends from ground level to roughly 11 kilometers (7 miles) above sea level

Front 15

stratosphere

Back 15

The region of the atmosphere that spans altitudes of 11 kilometers to 48 kilometers (30 miles)

Front 16

mesosphere

Back 16

The region of the atmosphere that spans altitudes of 48 kilometers to 80 kilometers (50 miles)

Front 17

jet streams

Back 17

Narrow bands of high-speed winds that circle the earth, blowing from west to east

Front 18

heat

Back 18

Energy that is being transferred

Front 19

temperature

Back 19

A measure of the energy of motion in a substance's molecules

Front 20

thermosphere

Back 20

The region of the atmosphere between altitudes of 80 kilometers and 460 kilometers

Front 21

exosphere

Back 21

The region of the atmosphere above an altitude of 460 kilometers

Front 22

ionosphere

Back 22

The region of the atmosphere between the altitudes of 65 kilometers and 330 kilometers where the gases are ionized

Front 23

electrolysis

Back 23

Using electricity to break a molecule down into its constituent elements

Front 24

polar molecule

Back 24

A molecule that has slight positive and negative charges due to an imbalance in the way electrons are shared

Front 25

solvent

Back 25

A liquid substance capable of dissolving other substances

Front 26

solute

Back 26

A substance that is dissolved in a solvent

Front 27

cohesion

Back 27

The phenomenon that occurs when individual molecules are so strongly attracted to each other that they tend to stay together, even when exposed to tension

Front 28

hard water

Back 28

Water that has certain dissolved ions in it, predominately calcium ions

Front 29

earth's crust

Back 29

Earth's outermost layer of rock

Front 30

sediment

Back 30

A deposit of sand and mineral fragments, usually laid down by water

Front 31

sedimentary rock

Back 31

rock formed when heat, pressure, and chemical reactions cement sediments together

Front 32

igneous rock

Back 32

Rock that forms from molten rock

Front 33

metamorphic rock

Back 33

Igneous or sedimentary rock that has been changed into a new kind of rock as a result of great pressure and temperature

Front 34

plastic rock

Back 34

Rock that behaves like something between a liquid and a solid

Front 35

earthquake

Back 35

A trembling or shaking of the earth as a result of rock masses suddenly moving along a fault

Front 36

fault

Back 36

The boundary between a section of moving rock and a section of stationary rock

Front 37

focus

Back 37

The point along a fault where an earthquake begins

Front 38

epicenter

Back 38

The point on the surface of the earth directly above an earthquake's focus

Front 39

aphelion

Back 39

The point at which the earth is farthest from the sun

Front 40

perihelion

Back 40

The point at which the earth is closest to the sun

Front 41

lines of longitude

Back 41

Imaginary lines that run north and south across the earth

Front 42

lines of latitude

Back 42

Imaginary lines that run east and west across the earth

Front 43

coriolis effect

Back 43

The way in which the rotation of the earth bends the path of winds, sea currents, and objects that fly through different latitudes

Front 44

air mass

Back 44

A large body of air with relatively uniform pressure, temperature, and humidity

Front 45

weather front

Back 45

A boundary between two air masses

Front 46

updraft

Back 46

A current of rising air

Front 47

insulator

Back 47

A substance that does not conduct electricity very well