
(M,A) Compare with atomic number and atomic weight. The total number of protons and neutrons in an atom or ion. In nuclide symbols the mass number is given as a leading superscript. In isotope names (e. g. carbon-14, sodium-23) the mass number is the number following the element name.
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The mass number (A), also called atomic mass number or nucleon number, is the total number of protons and neutrons (together known as nucleons) in an atomic nucleus. Because protons and neutrons both are baryons, the mass number A is identical with the baryon number B as of the nucleus as of the whole atom or ion. The mass number is different for ...
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in nuclear physics, the sum of the numbers of protons and neutrons present in the nucleus of an atom. The mass number is commonly cited in ... [5 related articles]
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the total number of protons and neutrons in an atomic nucleus.
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is the relative mass of the isoes compared to that of Carbon-12 whose mass is 12.0000 g/mol. It is not shown on the periodic chart. It is also equal to the sum of protons + neutrons inasmuch as protons and neutrons each have an atomic mass of 1 g/mol (amu
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http://www.chemicalglossary.net/definition/1119-MASS_NUMBER

The number of protons and neutrons in an atom.
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The sum of the numbers of protons and neutrons in an atom; an integer.
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The number of protons and neutrons in one atom of a particular isotope of an element. Mass number is also known as the nucleon number since protons and neutrons are collectively known as nucleons. Although all atoms of a given element have the same atomic number, their mass number can differ dependi...
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number of nucleons contained in an atomic nucleus
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the number of nucleons in an atomic nucleus
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The number of protons plus neutrons in the nucleus of an atom.
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The mass of the atom of a particular isotope relative to hydrogen-1 (or to 1/12 the mass of carbon-12), generally very close to the whole number represented by the sum of the protons and neutrons in the atomic nucleus of the isotope (indicated in the name or symbol of the isotope; e.g., oxygen-16, 16O); not to be confused with the atomic weight of ...
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(A) the number of nucleons (protons and neutrons) in the atom of a nuclide; generally indicated by a superscript preceding the symbol of a chemical element (such as 131I), denoting a specific isotope.
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the total number of protons and neutrons in an atomic nucleus.
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Type: Term Definitions: 1. the mass of the atom of a particular isotope relative to hydrogen-1 (or to 1/12 the mass of carbon 12); generally very close to the whole number represented by the sum of the protons and neutrons in the atomic nucleus of the isotope (indicated in the name or symbol of the isotope, oxygen-16, 16O); not to be confused with ...
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Total number of neutrons and protons in the nucleus of an atom. Approximate measure of the mass of an atom. Also see atomic number.
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The number of protons and neutrons in an atom.
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[
n] - the sum of the number of neutrons and protons in an atomic nucleus
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The sum of the number of neutrons and protons in a nucleus.
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The mass number (A) of an atom is the number of protons and neutrons it has in its nucleus; e.g., A = 35 for a chlorine atom which contains 18 neutrons (35Cl), and A = 37 for one which contains 20 neutrons (
37Cl).Click on an item to paste into clipboard or use clipboard symbol at end to clipboard all values Beryllium 9 Clip Carbon 12 Cli...
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nucleon number noun the sum of the number of neutrons and protons in an atomic nucleus
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The sum of the number of neutrons and protons in a nucleus.
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Sum of the numbers of protons and neutrons in the nucleus of an atom. It is used along with the atomic number (the number of protons) in nuclear notation: in symbols that represent nuclear isotopes, such as
146C, the lower number is the atomic number, and the upper number is the mass number. Since t...
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