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 ...

For now, they're known by working names, like ununseptium and ununtrium — two of the four new chemical elements whose discovery has been officially verified. The elements with atomic numbers 113, 115, ...

Chemistry textbooks as we know it are officially out of date, as four new elements will soon be added to the periodic table. Elements 113, 115, 117 and 118 have formally been recognized by the ...