Avogadro's number (redirected from Avogadro number)

number /num·ber/ (num´ber) a symbol, as a figure or word, expressive of a certain value or a specified quantity determined by count.

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atomic number  (Z ) a number expressive of the number of protons in an atomic nucleus.

Avogadro's number  (N ) (N A) the number of molecules in one mole of a substance: 6.023 × 1023.

mass number  (A ) the number expressive of the mass of a nucleus, being the total number of protons and neutrons in the nucleus of an atom or nuclide.

oxidation number  a number assigned to each atom in a molecule or ion that represents the number of electrons theoretically lost (negative numbers) or gained (positive numbers) in converting the atom to the elemental form (which has an oxidation number of zero). The sum of the oxidation numbers for all atoms in a neutral compound is zero; for polyatomic ions, it is equal to the ionic charge.

tooth number  a number assigned for each of the permanent teeth in consecutive order, with 1 for the upper right third molar and 17 for the lower left third molar, and proceeding around each jaw.

turnover number  the number of molecules of substrate acted upon by one molecule of enzyme per minute.

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Avogadro's number

n.

The number of molecules in a mole of a substance, approximately 6.0225 × 10²³. Also called Avogadro's constant.

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Avogadro's number,

the number of atoms in exactly 12 g of the isotope of carbon ¹²C, or 6.02 × 10²³. One mole of any monoatomic element contains this number of atoms and one mole of any polyatomic element or molecule contains this number of molecules.

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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) (N_A) 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.

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Avogadro's number,

n.pr the number of molecules that exist in one mole: 6.0225 × 10²³.

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number

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

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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

see reynold's number.