By: Dana S. Uranium U is a metallic, silver-gray element that is a member of the actinide series. It is the principle fuel for nuclear reactors, but it also used in the manufacture of nuclear weapons. Uranium has an atomic number of 92 which means there are 92 protons and 92 electrons in the atomic structure. U has neutrons in the nucleus, but the number of neutrons can vary from to Because uranium is radioactive, it is constantly emitting particles and changing into other elements.
Uranium has a well-established radioactive decay series. U and U which has neutrons are the most common isotopes of uranium. What is the isotope notation for cobalt? In an isotope, which part of the atom changes? What are some examples of isotope notations? What are some common mistakes students make with isotope notation? What is an isotope? What does the superscript of an isotope notation mean? What is the difference between isotope notation and hyphen notation?
What is the advantage of using isotope notation instead of hyphen notation? What are isotopes? The isotopes of an element are all the atoms that have in their nucleus the number of protons atomic number corresponding to the chemical behavior of that element.
However, the isotopes of a single element vary in the number of neutrons in their nuclei. Since they still have the same number of protons, all these isotopes of an element have identical chemical behavior. But since they have different numbers of neutrons, these isotopes of the same element may have different radioactivity. An isotope that is radioactive is called a radioisotope or radionuclide.
Two examples may help clarify this. The most stable isotope of uranium, U, has an atomic number of 92 protons and an atomic weight of 92 protons plus neutrons. The isotope of uranium of greatest importance in atomic bombs, U, though, has three fewer neutrons.
Thus, it also has an atomic number of 92 since the number of protons has not changed but an atomic weight of 92 protons plus only neutrons. The chemical behavior of U is identical to all other forms of uranium, but its nucleus is less stable, giving it higher radioactivity and greater susceptibility to the chain reactions that power both atomic bombs and nuclear fission reactors.
Another example is iodine, an element essential for health; insufficient iodine in one's diet can lead to a goiter. Iodine also is one of the earliest elements whose radioisotopes were used in what is now called nuclear medicine. The most common, stable form of iodine has an atomic number of 53 protons and an atomic weight of 53 protons plus 74 neutrons. Because its nucleus has the "correct" number of neutrons, it is stable and is not radioactive.
A less stable form of iodine also has 53 protons this is what makes it behave chemically as iodine but four extra neutrons, for a total atomic weight of 53 protons and 78 neutrons. With "too many" neutrons in its nucleus, it is unstable and radioactive, with a half-life of eight days. Because it behaves chemically as iodine, it travels throughout the body and localizes in the thyroid gland just like the stable form of iodine. But, because it is radioactive, its presence can be detected.
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