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 ?
Answers: 1) elements; 2) nucleus; 3) protons, neutrons; 4) electrons; 5) atomic number Bonus Answer: periodic table
The only element whose atomic number is equal to the sum of the letter values in its symbol is aluminium.
However, distribution of isotopes depending on a atomic number of the elements (Fig.
Who on earth would know the atomic number for Lawrencium?
This calculation accounts for deviations from a linear relationship between the k factor and composition with an atomic number correction for back-scattered electrons, a correction for the absorption of any generated x-rays, and a correction for secondary x-ray fluorescence.
Information obtained by these methods is elemental not chemical in nature, and the low atomic number elements are not detected, generally those elements below sodium in atomic number.
The effect of background curvature is more likely to be significant for samples of high mean atomic number, since the continuum intensity is then greatest, and a given degree of curvature has a greater effect in terms of elemental concentration.
The real value of BSE images is the ability to distinguish the relative mean atomic number differences of features.
1896), detected a new element with the atomic number of 75.
The beryllium in the beam pipes is virtually transparent to the subatomic particles that the collider's builder, the European Organization for Nuclear Research (CERN), is searching for because of its low atomic number and low density.
Which element, used as a semiconductor, has the atomic number 14?
When we're done, I hang the posters by atomic number so it looks like a gigantic periodic table