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Boron (5 B) naturally occurs as isotopes 10 B and 11 B, the latter of which makes up about 80% of natural boron. There are 13 radioisotopes that have been discovered, with mass numbers from 7 to 21, all with short half-lives, the longest being that of 8 B, with a half-life of only 771.9(9) ms and 12 B with a half-life of 20.20(2) ms.
The nuclear industry enriches natural boron to nearly pure 10 B. The less-valuable by-product, depleted boron, is nearly pure 11 B. [149] Enriched boron or 10 B is used in both radiation shielding and is the primary nuclide used in neutron capture therapy of cancer.
A table or chart of nuclides is a two-dimensional graph of isotopes of the elements, in which one axis represents the number of neutrons (symbol N) and the other represents the number of protons (atomic number, symbol Z) in the atomic nucleus. Each point plotted on the graph thus represents a nuclide of a known or hypothetical chemical element.
Boron's most common isotope is 11 B at 80.22%, which contains 5 protons and 6 neutrons. The other common isotope is 10 B at 19.78%, which contains 5 protons and 5 neutrons. [18] These are the only stable isotopes of boron; however other isotopes have been synthesised. Boron forms covalent bonds with other nonmetals and has oxidation states of 1 ...
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This page uses the meta infobox {{Infobox isotopes (meta)}} for the element isotopes infobox.. This infobox contains the table of § Main isotopes, and the § Standard atomic weight.
The elements in group 13 are also capable of forming stable compounds with the halogens, usually with the formula MX 3 (where M is a boron-group element and X is a halogen.) [14] Fluorine, the first halogen, is able to form stable compounds with every element that has been tested (except neon and helium), [15] and the boron group is no exception.
The elements commonly classified as metalloids are boron, silicon, germanium, arsenic, antimony and tellurium. [ n 4 ] The status of polonium and astatine is not settled. Most authors recognise one or the other, or both, as metalloids; Herman, Hoffmann and Ashcroft, on the basis of relativistic modelling, predict astatine will be a monatomic metal.