mass number


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Related to mass number: Isotopy

number

 [num´ber]
a symbol, as a figure or word, expressive of a certain value or a specified quantity determined by count.
atomic number (Z) a number expressive of the number of protons in an atomic nucleus, or the positive charge of the nucleus expressed in terms of the electronic charge.
Avogadro's number (N) (NA) the number of molecules in one mole of a substance: 6.023 × 1023. Called also Avogadro's constant.
CT number the density assigned to a voxel in a CAT scan on an arbitrary scale on which air has a density −1000; water, 0; and compact bone +1000. See also hounsfield unit.
mass number (A) the number of nucleons (protons plus neutrons) in the atom of a nuclide; generally indicated by a superscript preceding the symbol of a chemical element (e.g., 131I), denoting a specific isotope.
oxidation number a number assigned to each atom in a molecule or ion that represents the number of electrons theoretically gained (positive oxidation numbers) or lost (negative numbers) in converting the atom to the elemental form.

mass num·ber

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, for example, oxygen-16, 16O); not to be confused with the atomic weight of an element, which may include a number of isotopes in their natural proportion.

mass number (A)

the sum of the number of protons and neutrons in the nucleus of an atom or isotope. See also atomic number.

mass number

The number of protons and neutrons in a nuclide (e.g., 14 in 14C).

mass num·ber

(mas nŭmbĕr)
Atomic mass 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 an element, which may include a number of isotopes in their natural proportion.

mass number,

n the total number of protons and neutrons within the nucleus of an atom. This number represents the atom's approximate mass.

mass number (A),

n the number of nucleons (protons and neutrons) in the nucleus of an atom.

mass

1. a lump or collection of cohering particles.
2. that characteristic of matter which gives it inertia.

mass-action ratios
the ratio of substrate to product, where the predominance of one, usually the substrate, over the other thermodynamically favors a particular direction for a reaction.
inner cell mass
an internal cluster of cells at the embryonic pole of the blastocyst which develops into the body of the embryo.
lean body mass
that part of the body including all its components except neutral storage lipid; in essence, the fat-free mass of the body.
mass medication
(or immunization, or treatment, or prophylaxis, or testing, or screening) application of the procedure to all of the animals in the population, which may be as small as a herd or as large as a national herd. This sort of strategy has been used extensively and for many years in the control of diseases of animals, and has been the principal reason for the dramatic virtual eradication of the major plagues in many countries. The unintelligent extension of the strategy to the control of wastage caused by endemic disease has contributed most to the problem of residues of antibacterial drugs in the human food chain. See also mass medication.
mass number
the number used to express the mass of a nucleus, being the total number of nucleons, protons and neutrons in the nucleus of an atom or nuclide; symbol A.
mass reflex
reflex actions by all the body parts controlled by the part of the spinal cord which has been injured.
thalamic intermediate mass

number

a symbol, as a figure or word, expressive of a certain value or a specified quantity determined by count.

atomic number
a number expressive of the number of protons in an atomic nucleus, or the positive charge of the nucleus expressed in terms of the electronic charge; symbol A.
Avogadro's number
see avogadro's number.
mass number
see mass number.
Reynold's number
References in periodicals archive ?
The GCA effects for 119R, K4S, and N1S were significantly different from zero for gall number, and the GCA effects for 119R, 81R, K4S, and N1S were different from zero for egg mass number.
The confidence in this theory encouraged the extension of its application to nucleus-nucleus collisions but this was faced with computational difficulties [14-19] for collisions between two nuclei of mass numbers A, B [?
For an element 126 (on hypothesis) the mass number should be 310, but by our data it is 327.
Fraser Valley Conservancy studies indicated the amphibians had previously been perishing in mass numbers due to existing infrastructure.
We have mass numbers attached to our social media platforms including Facebook, where we have 45,000 followers.
This very important Supreme Court case illustrated major changes in America but it did not completely end segregation, and the prevalence of incarceration did emerge in mass numbers, especially for African Americans.
24,248 natural increase in electoral mass numbers in 2014 compared to 2010.
The whole idea of framing mass numbers of buildings quickly using dimensional lumber, that's a development that happened in the 19th century,'' said John Russick, director of curatorial affairs for the Chicago History Museum.
immigration officials scrambling to handle mass numbers of Central American migrants who, by law, the government cannot immediately deport, as they normally could illegal border crossers of Mexican or Canadian origin.
Yes, it's only fair that the right to kill and be killed in mass numbers be an equal opportunity activity for all, regardless of gender.
Furthermore, the government's profiling of civil servants with regard to their beliefs, ideologies and lifestyles and their removals in mass numbers are also unacceptable, he added.
Because program officials want the work done by the core members, and not by the four associates working with them, the capacity to produce quickly in mass numbers remains low, Ghareeb said.