Scientists have started a new periodic table for quantum dots, which they refer to as “artificial atoms.” Quantum dots are nano-sized particles that are made of semiconducting materials.

One in 5 Americans can't name a single element on the Periodic Table. Most Americans surveyed (59 percent) couldn't name more than 10 elements of the 118 that grace the Periodic Table.

Those particles, they propose, aren’t lightweight at all and could come in all kinds of “species” — with their own “dark matter periodic table” of invisible elements, originally formed ...

The periodic table, first invented by Dmitri Mendeleev in 1869, groups the 118 known chemical elements according to their chemical properties.

Mendeleev’s periodic table had three important features: He arranged the elements in order of increasing atomic mass. He put elements with similar properties in the same group.