| A | B |
|---|
| energy given off by an element | radioactivity |
| the splitting of atomic nuclei | fission |
| the joining together of light nuclei to form an atom with a heavier nucleus and to release energy | fusion |
| early nuclear reactor | atomic pile |
| nuclear reactor that produces more fuel than it uses | breeder reactor |
| a form of hydrogen with twice the atomic mass of normal hydrogen | deuterium |
| used to slow down the speed of neutrons in a fission reactor | moderator |
| amount of fuel needed to start a fission chain reaction | critical mass |
| an ore of uranium | pitchblende |
| type of particle accelerator | cyclotron |
| the resulting elements have a different atomic mass than the oringinl elements | both |
| uses uranium-235 or polonium as a nuclear fuel | fission |
| the reaction takes place in a nuclear reactor | fusion |
