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 ?
It is important to note that there is a close relation between the mass number and the atomic weight.
The White House Project is dedicated to getting women in leadership positions in every sector of political society and we need to have mass numbers of women running for office to make a dent in the lack of women that hold public office, " Wilson said.
Since objective test items only, are used in standardized tests, machine scoring is possible of mass numbers of tests.
But with 150,000 people dying every year from global warming, Greenpeace feels we're in a climate crisis - and if humanity is to solve the problem we need radical action, the kind of action that can only be forced through by mass numbers of people taking action to display the strength of feeling out there.
One of the first results of this work is currently underway and involves a direct mail campaign which, while reaching mass numbers, is at the same time highly targeted.
Furthermore, our niche products have no need to match the mass numbers of those media.
While METI aims to require mail-order businesses sending e-mail advertisements to protect consumers, the LDP bill aims to prevent such ads, often sent in mass numbers, from causing disruption to communication lines, he said.
We tried on umpteen occasions, when aircraft were taking off in mass numbers," he says.
In conclusion, egg mass numbers were depressed in female tests and snail numbers were depressed in the presence of both males and females.
While these lone wolves might not be able to kill in mass numbers, the Boston Marathon bombings and the Fort Hood slayings show that alienated persons influenced partially by online messaging can cause great damage.
When you've got teams that close, train travel is convenient so you get mass numbers arriving somewhere all together and that presents challenges.
It is very useful for a photographer who wishes to handle a mass numbers of passport photos in a easy way.