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atomic number

[uh-tom-ik nuhm-ber] / əˈtɒm ɪk ˈnʌm bər /


Example Sentences

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One of the most critical rare earths is dysprosium, atomic number 66 on the periodic table.

From The Wall Street Journal Oct. 11, 2025

Lighter elements -- generally those with an atomic number of 20 or lower on the periodic table -- often have an equal number of protons and neutrons.

From Science Daily Feb. 26, 2024

Katie Hafner: Uranium is the last of the naturally occurring elements on the periodic table, with an atomic number of 92.

From Scientific American Sep. 7, 2023

For in truth, how does it really benefit most of us to know why sodium’s atomic number is 11 and magnesium’s 12?

From Washington Post Apr. 28, 2023

The horizontal rows, meanwhile, arrange the chemicals in ascending order by the number of protons in their nuclei–what is known as their atomic number.

From "A Short History of Nearly Everything" by Bill Bryson




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