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In chemistry, the decay technique is a method to generate chemical species such as radicals, carbocations, and other potentially unstable covalent structures by radioactive decay of other compounds. For example, decay of a tritium -labeled molecule yields an ionized helium atom, which might then break off to leave a cationic molecular fragment.
This page lists radioactive nuclides by their half-life.
Any decay daughters that are the result of an alpha decay will also result in helium atoms being created. Some radionuclides may have several different paths of decay. For example, 35.94(6) % [27] of bismuth-212 decays, through alpha-emission, to thallium-208 while 64.06(6) % [27] of bismuth-212 decays, through beta-emission, to polonium-212.
There is a half-life describing any exponential-decay process. For example: As noted above, in radioactive decay the half-life is the length of time after which there is a 50% chance that an atom will have undergone nuclear decay. It varies depending on the atom type and isotope, and is usually determined experimentally. See List of nuclides.
The stages or steps in a decay chain are referred to by their relationship to previous or subsequent stages. Hence, a parent isotope is one that undergoes decay to form a daughter isotope. For example element 92, uranium, has an isotope with 144 neutrons (236 U) and it decays into an isotope of element 90, thorium, with 142 neutrons (232 Th ...
Five general stages are typically used to describe the process of decomposition in vertebrate animals: fresh, bloat, active decay, advanced decay, and dry/remains. [8] The general stages of decomposition are coupled with two stages of chemical decomposition: autolysis and putrefaction. [9]
Radiation chemistry is the study of the chemical effects of radiation on matter; this is very different from radiochemistry as no radioactivity needs to be present in the material which is being chemically changed by the radiation. An example is the conversion of water into hydrogen gas and hydrogen peroxide. Prior to radiation chemistry, it ...
The decay scheme of a radioactive substance is a graphical presentation of all the transitions occurring in a decay, and of their relationships. Examples are shown below. It is useful to think of the decay scheme as placed in a coordinate system, where the vertical axis is energy, increasing from bottom to top, and the horizontal axis is the proton number, increasing from left to right.