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Which element has the lowest atomic number in the periodic table?
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periodic table
Modern version of the periodic table of the elements. To learn an element's name, atomic number, electron configuration, atomic weight, and more, select one from the table.
The element with the lowest atomic number in the periodic table is hydrogen.
The atomic number, denoted by Z, represents the number of protons in an atom's nucleus. Hydrogen has an atomic number of 1, meaning its nucleus consists of a single proton. As the simplest member of the chemical elements, it occupies the first position in the periodic table.123