The periodic table is an icon. But chemists still can’t agree on how to arrange it
One hundred fifty years after Russian chemist Dmitri Mendeleev published his system for neatly arranging the elements, the periodic table it gave birth to hangs in every chemistry classroom in the world and is one of the field’s most recognizable symbols. But the solid squares and familiar patterns of today’s table mask one of its fundamental characteristics: “the” periodic table does not exist.
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