A system of knowledge and the methods you use to find that knowledge.

An organized plan for gathering, organizing and communicating information.

The variable that causes a change in another.

A well-tested explanation for a set of observations or experimental results.

Describes an observed pattern in nature.

The amount of matter in an object.

The amount of space taken up by an object.

A measure of how hot or cold an object is compared to a reference point.

The energy an object has due to its motion.

A state of matter in which materials have a definite shape and definite volume.

A state of matter in which materials have an indefinite volume and an indefinite shape.

A state of matter in which materials have a definite volume but an indefinite shape.

A chemical reaction that absorbs energy from its surroundings.

A chemical reaction that releases energy to its surroundings.

A temperature of 0 Kelvin.

A reversible physical change that occurs when a substance changes from one state to another.

A set of measuring units.

The phase change in which a substance changes from liquid into a gas.

The phase change in which a substance changes from gas or vapor to a liquid.