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11 Cards in this Set
- Front
- Back
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Types of Radiation |
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Alpha Decay |
In alpha decay, the nucleus emits an alpha particle, or a particle containing two protons and two neutrons The nucleus is said to decay, or change into one that is a little lighter, one with four less particles Alpha particles are relatively heavy and quite slow-moving They can be blocked very easily by air, paper, clothing, and even your skin |
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Beta Decay |
Occurs when a neutron turns into a proton and an electron is emitted Beta decay occurs when the nucleus contains too many neutrons Unlike alpha particles, beta particles are high-energy and very light They can travel through paper and certain types of clothing, but they are usually stopped by the first couple layers of your skin. To shield beta particles, a sheet of aluminum is needed. |
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Gamma Decay |
Occurs when the nucleus of an atom is very high in energy Also like electrons, when these particles fall back down into lower energy levels, radiation is released. When it is released from the nucleus by having protons and neutrons falling back down, very high energy gamma rays are released Blocking a gamma ray is difficult, and requires a thick layer of lead to absorb the radiation |
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Mass Number |
Which is the number of protons and neutrons (top number on example) |
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Half Life of Radioactive Isotopes |
Which is the amount of time it takes for half of a sample to react When there is only one remaining, it becomes a probability of a 50% chance to change (you cannot have half an atom), after another 5.3 years there is once again a 50% chance etc... |
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A 6.95 gram sample of radioactive nobelium-259 has a half-life of 58 min. How much is left after 2 hours and 54 minutes? |
0.869 grams |
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Cobalt-57 has a half-life of about 272 days. If a sample has an initial mass of 2.24 grams and undergoes decay until it has a mass of 0.140 grams, how many half-lives passed? |
4 |
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Nuclear Chemistry |
Is a field of chemistry that deals with the use of radioactive isotopes and other nuclear reactions |
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Nuclear Fusion |
Occurs when two or more atoms fuse together to form a single, heavier atom. The 'heavier' atom that is produced is actually lighter than the two individual pieces, which means that mass is lost. Because mass and energy are tied together, when mass is lost, energy is lost, or emitted. In a fusion reaction, massive amounts of energy are emitted. |
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Nuclear Fission |
Occurs when a heavier atom splits into smaller pieces. Usually the 'pieces' are smaller atoms, but often neutrons are also released. Many fission reactions are initiated by a very heavy atom being hit (or, in chemistry lingo, bombarded) by a neutron. This makes the already slightly unstable heavy atom even more unstable, which causes it to split into smaller atoms and possibly eject a few neutrons. This releases a lot of energy because the original atom was so unstable. Also, those neutrons that were ejected can be used to initiate several other fission reactions. This 'domino effect' caused by the neutrons is called a chain reaction, and it can be responsible for keeping the reaction going for a long time. |
