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Matter
Anything that occupies space and has mass.
Three main states of matter
Solid, liquid, gas
Molecule
A group of atoms bonded together.
Atom
Small building block or unit of matter.
Solid
Molecules are tightly packed together and don't move about much within the substance.
Liquid
Molecules are some distance apart and can move about and bump into one another within the substance.
Gas
Molecules are far apart and can move about freely within the substance.
Compressibility
Measures the change in volume resulting from applied pressure.
Melting
Occurs when a solid turns into a liquid.
Freezing
This is what happens when a liquid becomes solid.
Vaporization
Occurs when a liquid turns to vapor (gas).
Condensation
The opposite of vaporization; it occurs when a gas turns into a liquid.
Sublimation
When a solid becomes a gas, without ever becoming a liquid.
Phase diagram
A way to show the changes in the state of substance as it relates to temperature and pressure.