Ah... that's better, don't you agree?
Firstly, when Uranium in it's natural occurrence is discussed, inadvertently, U-238 is usually referenced, since it is the most abundant percentage of the mineral. However, U-234 and U-235 are Isotopes of U-238. Isotopes of an element have the same number of protons in the nucleus, but a different number of neutrons.
One major difference of importance in our discussion revolves around the fact that while U-238 has a half-life of 4.3 billion years, U-235 is about 700,000 years and U-234 is a mere 250,000 years or so. Each of these are radioactive, which means the nuclei spontaneously disintegrate or �decay.� (Source: U.S. Department of Energy Office of Depleted Uranium Hexafluoride Management Program. This "decay" consists of alpha particles (a collection of two protons and two neutrons) and gamma rays (an electromagnetic energy wave) (ibid.
The rate at which the nuclei in an isotope sample decay is called activity, which is the number of disintegrations (or emissions) that occur per second, which can then be calculated to determine the half-life of the element.
Contd.
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