atomic number


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Related to atomic number: Isotopes, atomic weight

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.

a·tom·ic num·ber (Z),

the number of protons in the nucleus of an atom; it indicates the position of the element in the periodic system.

atomic number

the number of protons in the nucleus of an atom of a particular element. In a neutral atom, the atomic number equals the number of electrons. See also atom, electron, proton.

a·tom·ic num·ber

(Z) (ă-tom'ik nŭm'bĕr)
The number of protons in the nucleus of an atom; it indicates the position of the element in the periodic system.

atomic number,

n the number of protons within an atom's nucleus.

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 mass fraction includes a bias in the proper direction due to the increase in neutron count in higher atomic number elements and so partially compensates for the screening effect, as noted by Armstrong.
For example, the element with atomic number 123 would be UNBITRIUM; the element with atomic number 444 would be QUADQUADQUADIUM; the element with atomic number 690 would be HEXENNILIUM; and the element with atomic number 999 would be ENNENNENNIUM.
Phase 4 was identical to Phases 1 and 2, but the stimuli were, "Name an atomic number.
Scientists identify elements by their atomic number (the number of protons in the element's nucleus).
The elements, recreated on a grand scale, consisted of a chemical symbol and atomic number printed on coloured banners to match the organisation of the Periodic Table.
It is shown that the atomic number Z is prime at the beginning of the each [s.
which provides information on the location and distribution of high atomic number components within a sample, has been widely used to examine both biological and non-biological samples.
9898), atomic number (11), and specific gravity (0.
At these energies, the photoelectric interaction is predominant and depends on the third power of the atomic number; so, in that region of energies there is an over-response in the case of materials having a higher atomic number [2].
Not only does it show surface morphology in stereoscopic detail, it also shows contrast due to different average atomic number composition within the sample.
15 is the atomic number of the element phosphorus, which means it is the fifteenth lightest element.