atomic number

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Related to atomic number: Isotopes, atomic weight

atomic number

n. Symbol Z Abbr. at. no.

The number of protons in an atomic nucleus.

American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

atomic number

(General Physics) the number of protons in the nucleus of an atom of an element. Abbreviation: at. no. Symbol: Z Also called: proton number

Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

atom′ic num′ber

the number of protons in the nucleus of an atom of a given element, used to locate the element in the periodic table. Abbr.: at. no.; Symbol: Z

[1815–25]

atomic number

The number of protons in the nucleus of an atom. In electrically neutral atoms, this number is also equal to the number of electrons orbiting about the atom's nucleus. The atomic number of an element determines its position in the Periodic Table.

The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

atomic number

1. Or proton number (Z) The number of protons in the nucleus of an atom. If not electrically charged, this is equal to the number of electrons in its shells.

2. The number of protons in the nucleus of an atom.

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Noun

atomic number - the order of an element in Mendeleyev's table of the elements; equal to the number of protons in the nucleus or electrons in the neutral state of an atom of an element

number - a concept of quantity involving zero and units; "every number has a unique position in the sequence"

magic number - the atomic number of an extra stable strongly bound atomic nucleus: 2, 8, 20, 28, 50, 82 or 126

Translations

atomové číslo

Kernladungszahl Ordnungszahl

número atómico

numero atomico numero ordinale

原子番号

atoomnummer

atomnummer

原子序

atomic number

n (Chem) → numero atomico

Collins Italian Dictionary 1st Edition © HarperCollins Publishers 1995

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After he had finished looking at this particular issue, he came to me and said, "Mommy, let's see if you can guess the atomic numbers of the elements.

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At the 42nd General Assembly in Ottawa, ON, the International Union of Pure and Applied Chemistry (IUPAC) Council officially approved the name for the element of atomic number 110, to be known as darmstadtium.