For the last fifty or so years, the periodic table has been incomplete ... Researchers at these three laboratories will propose names and atomic symbols for these three elements.

That’s why this periodic table clock really caught our eye. [gocivici]’s idea is a simple one: light up three different elements with three different colors for hours, minutes, and seconds ...

SUNAYANA: Because elements have isotopes with different masses, we now need ... s idea led to the modern periodic table? NNICK: Mendeleev wrote the names of the elements onto cards and arranged ...