| Term | Definition |
| Matter | Everything that has mass and takes up space |
| Elements | The ingredients that make up all other substances. Can't be broken down into other substances. |
| Metals | Good conductors of electricity and heat. Can bendwithout breaking. Most have a gray color |
| Nonmetals | Do not conduct heat / electricity very well. May
be a gas or a solid |
| Semimetals | Sometimes like metals and sometimes like
nonmetals |
| Atom | The smallest part of an element that still acts like
that element |
| Atomic Theory | States that everything is made of atoms |
| Compound | A type of matter made of two or more elements |
| Molecule | Smallest particle of a compound that still acts like
that compound |
| Proton | Positive charge. Found in the nucleus |
| Neutron | No charge. Found in the nucleus |
| Electron | Negative charge. Orbits the nucleus |
| Solid | Has a definite volume or shape. Particles are very close together,
and don’t move past each other. Keeps its shape. |
| Liquid | Has a definite volume but not shape. Particles can move past each other. Takes shape of container |
| Gas | No definite volume or shape. Particles spread out evenly and take
shape of container. Can be squeezed into a smaller volume |
| Plasma | Like a gas, but conducts electricity like a metal. Occurs with high
temps or electric charge |
| Melting Point | Solid to liquid or liquid to solid. Same temperature as freezing point. |
| Evaporation | When liquids become a gas |
| Condensation | When gas becomes a liquid. Gas particles touch a cold surface and the temperature drops. |
| Boiling Point | The temperature at which evaporation occurs |
