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Neon-22
Neon (10Ne) possesses three stable isotopes: , , and . In addition, 17 radioactive isotopes have been discovered, ranging from to , all short-lived. The longest-lived is with a half-life of . All others are under a minute, most under a second. The least stable is with a half-life of (). See isotopes of carbon for notes about the measurement. Light radioactive neon isotopes usually decay to fluorine or oxygen, while heavier ones decay to sodium. List of isotopes , -id=Neon-15 , , style="text-align:right" , 10 , style="text-align:right" , 5 , , [] , proton emission, 2p , , (3/2−) , , , -id=Neon-16 , , style="text-align:right" , 10 , style="text-align:right" , 6 , , > [ , -id=Neon-21 , , style="text-align:right" , 10 , style="text-align:right" , 11 , , colspan=3 align=center, Stable , 3/2+ , , ref name="Isotopic Composition of Elements" /> , -id=Neon-22 , , style="text-align:right" , 10 , style="text-align:right" , 12 , , c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isotope
Isotopes are distinct nuclear species (or ''nuclides'') of the same chemical element. They have the same atomic number (number of protons in their Atomic nucleus, nuclei) and position in the periodic table (and hence belong to the same chemical element), but different nucleon numbers (mass numbers) due to different numbers of neutrons in their nuclei. While all isotopes of a given element have similar chemical properties, they have different atomic masses and physical properties. The term isotope is derived from the Greek roots isos (wikt:ἴσος, ἴσος "equal") and topos (wikt:τόπος, τόπος "place"), meaning "the same place"; thus, the meaning behind the name is that different isotopes of a single element occupy the same position on the periodic table. It was coined by Scottish doctor and writer Margaret Todd (doctor), Margaret Todd in a 1913 suggestion to the British chemist Frederick Soddy, who popularized the term. The number of protons within the atomic nuc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neon Chart
Neon is a chemical element; it has symbol Ne and atomic number 10. It is the second noble gas in the periodic table. Neon is a colorless, odorless, inert monatomic gas under standard conditions, with approximately two-thirds the density of air. Neon was discovered in 1898 alongside krypton and xenon, identified as one of the three remaining rare inert elements in dry air after the removal of nitrogen, oxygen, argon, and carbon dioxide. Its discovery was marked by the distinctive bright red emission spectrum it exhibited, leading to its immediate recognition as a new element. The name ''neon'' originates from the Greek word , a neuter singular form of (), meaning 'new'. Neon is a chemically inert gas; although neon compounds do exist, they are primarily ionic molecules or fragile molecules held together by van der Waals forces. The synthesis of most neon in the cosmos resulted from the nuclear fusion within stars of oxygen and helium through the alpha-capture process. Despit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neon
Neon is a chemical element; it has symbol Ne and atomic number 10. It is the second noble gas in the periodic table. Neon is a colorless, odorless, inert monatomic gas under standard conditions, with approximately two-thirds the density of air. Neon was discovered in 1898 alongside krypton and xenon, identified as one of the three remaining rare inert elements in dry air after the removal of nitrogen, oxygen, argon, and carbon dioxide. Its discovery was marked by the distinctive bright red emission spectrum it exhibited, leading to its immediate recognition as a new element. The name ''neon'' originates from the Greek word , a neuter singular form of (), meaning 'new'. Neon is a chemically inert gas; although neon compounds do exist, they are primarily ionic molecules or fragile molecules held together by van der Waals forces. The synthesis of most neon in the cosmos resulted from the nuclear fusion within stars of oxygen and helium through the alpha-capture proce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neutron Emission
Neutron emission is a mode of radioactive decay in which one or more neutrons are ejected from a Atomic nucleus, nucleus. It occurs in the most neutron-rich/proton-deficient nuclides, and also from excited states of other nuclides as in photodisintegration, photoneutron emission and beta-delayed neutron emission. As only a neutron is lost by this process the number of protons remains unchanged, and an atom does not become an atom of a different element, but a different isotope of the same element. Neutrons are also produced in the spontaneous fission, spontaneous and nuclear fission, induced fission of certain heavy nuclides. Spontaneous neutron emission As a consequence of the Pauli exclusion principle, nuclei with an excess of protons or neutrons have a higher average energy per nucleon. Nuclei with a sufficient excess of neutrons have a greater energy than the combination of a free neutron and a nucleus with one less neutron, and therefore can decay by neutron emission. Nuclei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isotopes Of Carbon
Carbon (6C) has 14 known isotopes, from to as well as , of which only and are stable. The longest-lived radioisotope is , with a half-life of years. This is also the only carbon radioisotope found in nature, as trace quantities are formed cosmogenically by the reaction + → + . The most stable artificial radioisotope is , which has a half-life of . All other radioisotopes have half-lives under 20 seconds, most less than 200 milliseconds. The least stable isotope is , with a half-life of . Light isotopes tend to decay into isotopes of boron and heavy ones tend to decay into isotopes of nitrogen. List of isotopes , -id=Carbon-8 , , style="text-align:right" , 6 , style="text-align:right" , 2 , , [] , proton emission, 2p , Also immediately emits two protons for the net reaction of → + 4 , 0+ , , , -id=Carbon-9 , rowspan=3, , rowspan=3 style="text-align:right" , 6 , rowspan=3 style="text-align:right" , 3 , rowspan=3, , rowspan=3, , ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isotopes Of Nitrogen
Natural nitrogen (7N) consists of two stable isotopes: the vast majority (99.6%) of naturally occurring nitrogen is nitrogen-14, with the remainder being nitrogen-15. Thirteen radioisotopes are also known, with atomic masses ranging from 9 to 23, along with three nuclear isomers. All of these radioisotopes are short-lived, the longest-lived being nitrogen-13 with a half-life of . All of the others have half-lives shorter than ten seconds, with most of these being below 500 milliseconds. Most of the isotopes with atomic mass numbers below 14 decay to isotopes of carbon, while most of the isotopes with masses above 15 decay to isotopes of oxygen. The shortest-lived known isotope is nitrogen-10, with a half-life of , though the half-life of nitrogen-9 has not been measured exactly. List of isotopes , -id=Nitrogen-9 , , style="text-align:right" , 7 , style="text-align:right" , 2 , , , , -id=Nitrogen-14m , style="text-indent:1em" , , colspan="3" style="text-ind ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isotopes Of Oxygen
There are three known stable isotopes of oxygen (8O): , , and . Radioactive isotopes ranging from to have also been characterized, all short-lived. The longest-lived radioisotope is with a half-life of , while the shortest-lived isotope is the unbound with a half-life of , though half-lives have not been measured for the unbound heavy isotopes and . List of isotopes , -id=Oxygen-11 , , style="text-align:right" , 8 , style="text-align:right" , 3 , , [] , proton emission, 2p , , (3/2−) , , , -id=Oxygen-12 , , style="text-align:right" , 8 , style="text-align:right" , 4 , , , 2p , , 0+ , , , - , rowspan=3, , rowspan=3 style="text-align:right" , 8 , rowspan=3 style="text-align:right" , 5 , rowspan=3, , rowspan=3, , β+ () , , rowspan=3, (3/2−) , rowspan=3, , rowspan=3, , - , β+p () , , - , β+p,α ( , - , Can be used in NMR studies of metabolic pathways. , style="text-align:right" , 8 , style="text-align:right ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isotopes Of Fluorine
Fluorine (9F) has 19 known isotopes ranging from to and two isomers ( and ). Only fluorine-19 is stable and naturally occurring in more than trace quantities; therefore, fluorine is a monoisotopic and mononuclidic element. The longest-lived radioisotope is ; it has a half-life of . All other fluorine isotopes have half-lives of less than a minute, and most of those less than a second. The least stable known isotope is , whose half-life is , corresponding to a resonance width of . List of isotopes , -id=Fluorine-13 , , style="text-align:right" , 9 , style="text-align:right" , 4 , # , , p ?Decay mode shown is energetically allowed, but has not been experimentally observed to occur in this nuclide. , ? , 1/2+# , , -id=Fluorine-14 , , style="text-align:right" , 9 , style="text-align:right" , 5 , , [] , p ?Decay mode shown is energetically allowed, but has not been experimentally observed to occur in this nuclide. , ? , 2− , , -id=Fluorine-15 , ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isotopes Of Sodium
There are 20 isotopes of sodium (11Na), ranging from to (except for the still-unknown 36Na and 38Na), and five isomers (two for , and one each for , , and ). is the only stable (and the only primordial) isotope. It is considered a monoisotopic element and it has a standard atomic weight of . Sodium has two radioactive cosmogenic isotopes (, with a half-life of ; and , with a half-life of ). With the exception of those two isotopes, all other isotopes have half-lives under a minute, most under a second. The shortest-lived is the unbound , with a half-life of seconds (although the half-life of the similarly unbound 17Na is not measured). Acute neutron radiation exposure (e.g., from a nuclear criticality accident) converts some of the stable (in the form of Na+ ion) in human blood plasma to . By measuring the concentration of this isotope, the neutron radiation dosage to the victim can be computed. is a positron-emitting isotope with a remarkably long half-life. It is used to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Halo Nucleus
In nuclear physics, an atomic nucleus is called a halo nucleus or is said to have a nuclear halo when it has a core nucleus surrounded by a "halo" of orbiting protons or neutrons, which makes the radius of the nucleus appreciably larger than that predicted by the liquid drop model. Halo nuclei form at the extreme edges of the table of nuclides — the neutron drip line and proton drip line — and have short half-lives, measured in milliseconds. These nuclei are studied shortly after their formation in an ion beam. Typically, an atomic nucleus is a tightly bound group of protons and neutrons. However, in some nuclides, there is an overabundance of one species of nucleon. In some of these cases, a nuclear core and a halo will form. Often, this property may be detected in scattering experiments, which show the nucleus to be much larger than the otherwise expected value. Normally, the cross-section (corresponding to the classical radius) of the nucleus is proportional to the cube ro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proton Emission
Proton emission (also known as proton radioactivity) is a rare type of radioactive decay in which a proton is ejected from a atomic nucleus, nucleus. Proton emission can occur from high-lying excited states in a nucleus following a beta decay, in which case the process is known as beta-delayed proton emission, or can occur from the ground state (or a low-lying nuclear isomer, isomer) of very proton-rich nuclei, in which case the process is very similar to alpha decay. For a proton to escape a nucleus, the proton separation energy must be negative (Sp < 0)—the proton is therefore unbound, and quantum tunneling, tunnels out of the nucleus in a finite time. The rate of proton emission is governed by the nuclear, Coulomb, and centrifugal potentials of the nucleus, where centrifugal potential affects a large part of the rate of proton emission. The half-life of a nucleus with respect to proton emission is affected by the proton energy and its orbital angular momentum. Proton emiss ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
