atomic number(redirected from Atom number)
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n. Symbol Z Abbr. at. no.
The number of protons in an atomic nucleus.
(General Physics) the number of protons in the nucleus of an atom of an element. Abbreviation: at. no. Symbol: Z Also called: proton number
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
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.
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||1.||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