Uses of radioisotopes
Note: nuclear power works by radioactivity
“Radioisotopes are naturally occurring or synthetic radioactive form of an element. Most radioisotopes are made by bombarding a stable element with neutrons in the core of a nuclear reactor. The radiations given off by radioisotopes are easy to detect. Most natural isotopes of relative atomic mass less than 208 are not radioactive. Those from 210 and up are all radioactive.”(Radioisotope - Hutchinson Encyclopedia) (Radioisotopes image)
An example of such radioisotopes is uranium, which has been serving us for the past 50 years. Uranium is found in various parts of the world, this metal is used to produce about 11% of the world’s energy needs by different procedures. In 1956, the first large-scale nuclear power station started in England. Nuclear energy helped the world not just in power, but other aspects to do with nuclear too, some were medical uses and agriculture (Energy Resources: Nuclear power). The amount of energy released during each nuclear reaction is different, this is indicated in the formula below,
When radioisotopes are created, energy is released, allowing people to use it through various ways. Natural radioactive decay is a natural process, which an isotope spontaneously decays into another element through alpha, beta or gamma decay. In this process, four kinds of radioactive rays can be produced, alpha, beta, gamma, or neutron rays. Atoms that have a large nucleus tend to decay by alpha to reduce the size of their nucleus. When atoms have too many protons, extreme repulsion is caused and therefore a helium nucleus (also known as an alpha particle) is emitted, bumping with the walls of the nucleus. Beta decay is a high-energy electron that has lots of kinetic energy. This happens when the atom is unstable and the ratio of neutrons is that of when protons are high, and neutrons tend to turn into a proton and an electron. In the end comes the gamma radiation that accompanies a nuclear decay. It is basically high-energy electromagnetic radiations that are a result of energy released from a nucleus. (HowStuffWorks).
A reactor is used by a nuclear power station to extract the energy from isotopes. Nuclear power stations work like burning fossil fuels, however, a ‘chain reaction’ is used to create heat instead. A reactor in the station uses Uranium rods as fuel, using nuclear fission for heat. Nuclear fission is the process where the nucleus of an atom is split into two smaller parts producing a lighter nucleus and free neutrons hence inturn releasing energy. In a reactor, a neutron hits a uranium-235 atom; the neutron is absorbed into the atom creating uranium-236; a radioisotope. Uranium-236 causes the atom to go through the process of fission releasing some energy in the form of radiation and heat (Basic Nuclear Fission). This fission can produce some products, which their masses always add up to 236. For example: - 235U + 1 neutron 2 neutrons + 92Kr + 142Ba + ENERGY
An ongoing series of nuclear fission is called a chain-reaction. Fission is the action of dividing or splitting something into two or more parts. When a chain-reaction happens at a fast rate, more heat is produced which might cause the reactor to explode: too much gas in the reactor meaning excess pressure. For safety, a chain-reaction is controlled using control rods made of boron or cadmium. These control rods are lowered to reduce or stop the chain reaction. Moderators of graphite or water are included to slow the reaction down as the fission of uranium atoms works more effectively with slow neutrons. As a safety precaution, the whole reactor is protected with concrete and steel to absorb any gamma rays emitted. (Basic Nuclear Fission)
All isotopes behave identically and have same chemical properties. Radioisotopes can be detected using different methods according to the type of radiation it emits. This allows nuclear...
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