atomic number
noun
: an experimentally determined number characteristic of a chemical element that represents the number of protons in the nucleus which in a neutral atom equals the number of electrons outside the nucleus and that determines the place of the element in the periodic table see Chemical Elements Table
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Because 79 is the atomic number of the chemical element of gold.
—
Devorah Lev-Tov, Architectural Digest, 17 Oct. 2024
Lead, explained Lead — atomic number 82 on the periodic table — is soft, plentiful, and easy to mine and manipulate, which is why humans have been harnessing it for various purposes for thousands of years.
—Dylan Matthews, Vox, 7 Dec. 2018
The periodic table arranges elements based on their atomic number, or the number of protons each element has in its nucleus.
—Michael Irving, New Atlas, 25 July 2024
The elements heavier than iron (atomic number 26) form in nature through a process called rapid neutron capture, which often occurs in cataclysmic events such as a collision of two neutron stars.
—Stephanie Pappas, Scientific American, 14 May 2024
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Devorah Lev-Tov, Architectural Digest, 17 Oct. 2024
Lead, explained Lead — atomic number 82 on the periodic table — is soft, plentiful, and easy to mine and manipulate, which is why humans have been harnessing it for various purposes for thousands of years.
—Dylan Matthews, Vox, 7 Dec. 2018
The periodic table arranges elements based on their atomic number, or the number of protons each element has in its nucleus.
—Michael Irving, New Atlas, 25 July 2024
The elements heavier than iron (atomic number 26) form in nature through a process called rapid neutron capture, which often occurs in cataclysmic events such as a collision of two neutron stars.
—Stephanie Pappas, Scientific American, 14 May 2024
See all Example Sentences for atomic number
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“Atomic number.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/atomic%20number. Accessed 3 Dec. 2024.
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atomic number
noun
atomic num·ber
-ˈnəm-bər 
: an experimentally determined number characteristic of a chemical element that represents the number of protons in the nucleus which in a neutral atom equals the number of electrons outside the nucleus and that determines the place of the element in the periodic table see Chemical Elements Table
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