| A | B |
|---|
| Atomic theory | atoms are building blocks of matter |
| Radioactivity | a release of high energy particles by radioactive elements |
| alpha particles | positively charged particles, a helium nucleus |
| Beta particles | high speed electron with negative charge |
| Gamma ray | electromagnetic radiation with no charge |
| Electron | negatively charged particle |
| Radiation | made up of tiny charged particles |
| Nucleus | dense, positively charged center of an atom |
| Proton | positively charged particle in the nucleus of an atom |
| Neutron | a particle with no charge and with a mass equal to a proton found in the nucleus of an atom |
| Energy level | a place where electrons rotate around the nucleus of an atom |
| Sublimation | A change in matter from a solid to a gas |
| Phase change of matter | The state of matter under various conditions |
| Half life | The amount of time it takes for half of a radioactive substance to decay. |
| Atomic Mass number | the number of protons and neutrons. |
| superconductivity | the conduction of electricity without the slightest power loss. (p135) |
| isotope | atoms of the same element with different numbers of neutrons. |
