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Isotopes of beryllium AI simulator
(@Isotopes of beryllium_simulator)
Hub AI
Isotopes of beryllium AI simulator
(@Isotopes of beryllium_simulator)
Isotopes of beryllium
Beryllium (4Be) has 11 known isotopes and 3 known isomers, but only one of these isotopes (9
Be) is stable and a primordial nuclide. As such, beryllium is considered a monoisotopic element. It is also a mononuclidic element, because its other isotopes have such short half-lives that none are primordial and their abundance is very low. Beryllium is unique as being the only monoisotopic element with an even number of protons (even atomic number) and also has an odd number of neutrons; the 25 other monoisotopic elements all have odd numbers of protons (odd atomic number), and even of neutrons, so the total mass number is still odd.
Of the 10 radioisotopes of beryllium, the most stable are 10
Be with a half-life of 1.387 million years and 7
Be with a half-life of 53.22 days. All other radioisotopes have half-lives under 15 s, most under 30 milliseconds.
The 1:1 neutron–proton ratio seen in stable isotopes of many light elements (up to oxygen, and in elements with even atomic number up to calcium) is prevented in beryllium by the extreme instability of 8
Be toward splitting into two 4
He nuclei, which may be seen either alpha decay or a type of fission; in any case the half-life is only 8.2×10−17 s, short enough to normally be considered unbound. This, as with the relative instability of all lithium, beryllium, and boron isotopes, is favored due to the extremely tight binding of the helium-4 nucleus.
Beryllium is prevented from having a stable isotope with 4 protons and 6 neutrons by the very lopsided neutron–proton ratio for such a light element. Nevertheless, this isotope, beryllium-10, has a half-life above a million years and a decay energy less than 1 MeV, which indicates unusual stability given that condition.
Most beryllium present in the universe is thought to be formed by cosmic ray nucleosynthesis from cosmic ray spallation in the period between the Big Bang and the formation of the Solar System. The isotopes 7
Be and 10
Be are both cosmogenic nuclides because they are made, in the Solar System, continually at the rate they decay by spallation, as is carbon-14.
Beryllium-7 is an isotope with a half-life of 53.22 days that is generated naturally as a cosmogenic nuclide. It is also a nuisance byproduct in nuclear reactors and accelerators. The rate at which the short-lived 7
Be is transferred from the air to the ground is controlled in part by the weather. 7
Be decay in the Sun (the half-life in stars can be greatly different from the normal as it is a free rather than a bound electron that is captured) is one of the sources of solar neutrinos, and the first type ever detected using the Homestake experiment. Presence of 7
Be in sediments is often used to establish that they are fresh, i.e. less than about 3–4 months in age, or about two half-lives of 7
Be.
Beryllium-8 decays immediately into two alpha particles as its total energy is about 92 keV greater than that of the two alpha particles, and the Coulomb barrier to decay is negligible. This is unusual among light N = Z nuclides and creates a bottleneck in stellar nucleosynthesis, which requires that a third alpha be immediately captured, known as the fusion of three alpha particles, to form stable carbon-12 and thence all heavier elements.
Beryllium-10 has a half-life of 1.387×106 y, and beta decays to stable boron-10 with a maximum energy of 556.2 keV. It is formed in the Earth's atmosphere mainly by cosmic ray spallation on nitrogen and oxygen. 10Be and its daughter product have been used to examine soil erosion, soil formation from regolith, the development of lateritic soils and the age of ice cores. 10Be is a significant isotope used as a proxy data measure for cosmogenic nuclides to characterize solar and extra-solar attributes of the past from terrestrial samples.
Isotopes of beryllium
Beryllium (4Be) has 11 known isotopes and 3 known isomers, but only one of these isotopes (9
Be) is stable and a primordial nuclide. As such, beryllium is considered a monoisotopic element. It is also a mononuclidic element, because its other isotopes have such short half-lives that none are primordial and their abundance is very low. Beryllium is unique as being the only monoisotopic element with an even number of protons (even atomic number) and also has an odd number of neutrons; the 25 other monoisotopic elements all have odd numbers of protons (odd atomic number), and even of neutrons, so the total mass number is still odd.
Of the 10 radioisotopes of beryllium, the most stable are 10
Be with a half-life of 1.387 million years and 7
Be with a half-life of 53.22 days. All other radioisotopes have half-lives under 15 s, most under 30 milliseconds.
The 1:1 neutron–proton ratio seen in stable isotopes of many light elements (up to oxygen, and in elements with even atomic number up to calcium) is prevented in beryllium by the extreme instability of 8
Be toward splitting into two 4
He nuclei, which may be seen either alpha decay or a type of fission; in any case the half-life is only 8.2×10−17 s, short enough to normally be considered unbound. This, as with the relative instability of all lithium, beryllium, and boron isotopes, is favored due to the extremely tight binding of the helium-4 nucleus.
Beryllium is prevented from having a stable isotope with 4 protons and 6 neutrons by the very lopsided neutron–proton ratio for such a light element. Nevertheless, this isotope, beryllium-10, has a half-life above a million years and a decay energy less than 1 MeV, which indicates unusual stability given that condition.
Most beryllium present in the universe is thought to be formed by cosmic ray nucleosynthesis from cosmic ray spallation in the period between the Big Bang and the formation of the Solar System. The isotopes 7
Be and 10
Be are both cosmogenic nuclides because they are made, in the Solar System, continually at the rate they decay by spallation, as is carbon-14.
Beryllium-7 is an isotope with a half-life of 53.22 days that is generated naturally as a cosmogenic nuclide. It is also a nuisance byproduct in nuclear reactors and accelerators. The rate at which the short-lived 7
Be is transferred from the air to the ground is controlled in part by the weather. 7
Be decay in the Sun (the half-life in stars can be greatly different from the normal as it is a free rather than a bound electron that is captured) is one of the sources of solar neutrinos, and the first type ever detected using the Homestake experiment. Presence of 7
Be in sediments is often used to establish that they are fresh, i.e. less than about 3–4 months in age, or about two half-lives of 7
Be.
Beryllium-8 decays immediately into two alpha particles as its total energy is about 92 keV greater than that of the two alpha particles, and the Coulomb barrier to decay is negligible. This is unusual among light N = Z nuclides and creates a bottleneck in stellar nucleosynthesis, which requires that a third alpha be immediately captured, known as the fusion of three alpha particles, to form stable carbon-12 and thence all heavier elements.
Beryllium-10 has a half-life of 1.387×106 y, and beta decays to stable boron-10 with a maximum energy of 556.2 keV. It is formed in the Earth's atmosphere mainly by cosmic ray spallation on nitrogen and oxygen. 10Be and its daughter product have been used to examine soil erosion, soil formation from regolith, the development of lateritic soils and the age of ice cores. 10Be is a significant isotope used as a proxy data measure for cosmogenic nuclides to characterize solar and extra-solar attributes of the past from terrestrial samples.