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Nuclear Processes
Term | Definition |
---|---|
isotope | Atoms of the same element with different numbers of neutrons |
radioactive | Unstable nucleus; gives off radiation in the form of alpha particles, beta particles, and gamma rays |
Alpha Particle | Equivalent to a helium nucleus with 2 protons and 2 neutrons; positively charged particle emitted by certain radioactive nuclei; low energy |
Beta Particle | Electrons emitted by an unstable atom; more able to penetrate matter than alpha particles; can be stopped by lead (medium energy) |
Gamma Ray | High energy x-rays; can only be stopped by thick lead or concrete |
Radioactive decay | Causes an atom of one element to become a different element by reducing its atomic number |
Half life | The time required for one half of a sample of a radioactive isotope to decay |
fission | Occurs when the nucleus of an atom that has many protons and neutrons becomes so unstable that it splits into two smaller atoms; can be spontaneous or induced (Think: fissure) |
Spontaneous fission | Natural process that occurs mostly in the transactinide elements |
Induced fission | Process of firing neutrons at heavy atoms to make them split |
fusion | Opposite of fission; involves joining (fusing) two small atoms to form one larger atom; occurs in the sun and other stars where extremely high temperatures allow hydrogen isotopes to collide and fuse, releasing energy |
Fission fragments | Products of an atom split by neutron bombardment |
Decay chain | A sequence of decays |
Nuclear energy | Energy in the nucleus of an atom |
Mass- energy equation | Mass and energy can be changed into each other; credit it given to Einstein; E=mc (squared) |
Nuclear reactor | A nuclear reactor is a device in a power plant where fission takes place. The reactor has pieces of uranium stacked up in rods that form the core of the reactor. |
Control rods | The safeguard of the power plant–The rods are lowered into the uranium bundle to lessen the heat and raised out of the bundle to raise the heat. |
supercriticality | For the nuclear power plant to work, it must start in a slightly supercritical state.This is where the uranium rods heat up, react, and cause more neutrons to be produced.The control rods keep this from becoming out of control and causing a disaster. |
All elements with atomic number greater than ______ are radioactive. | 83 |