| A | B |
|---|
| atom | unit of matter |
| nucleus | the center of an atom |
| electron | negatively charged particle with no mass, not in the nucleus |
| proton | positively charged particle, 1 amu, in the nucleus |
| neutron | neutral particle, 1 amu, in the nucleus |
| atomic number | the number of protons in an atom |
| mass number | the number of particles in the nucleus, p+n |
| isotope | the same element with a different number of neutrons |
| strong force | the interation that binds nucleons together in a nucleus |
| element | a type of atom. Each one has a specific atomic number. |
| half-life | the time needed for half of the original nuclei of a smaple of a radioactive substance to undergo radioactive decay |
| fission | the process of a large atomic nucleus splitting into several smaller fragments |
| fusion | the process of two light nuclei combine to form a heavier nucleus |
| radioactive | the emission of from nuclei as a result of nuclear instability |
| transmutation | conversion of one nuclear element or isotope into another |
| chain reaction | a reaction where the product of one reaction causes another reaction |
| critical mass | the point where a reaction can be self-sustaining which means once started, continues without further outside influence |
