The periodic table is a well-organized chart that contains all the known elements in the universe. These elements are ...

was less than the atomic mass (average mass of the atom). For example, a helium atom has an atomic mass of 4, but an atomic number (or positive charge) of 2. Since electrons have almost no mass ...

Researchers at the Institute of Modern Physics (IMP) of the Chinese Academy of Sciences, together with their collaborators, ...

An curved arrow pointing right. North Korea recently claimed to test a hydrogen bomb. Some experts say it is more likely they tested a "boosted" atomic bomb. Although this type of bomb isn't ...

of~hydrogen} = \frac{mass~of~hydrogen ... is numerically equal to its relative formula mass or relative atomic mass For example, one mole of carbon is 12 g and contains 6 × 10 23 atoms of ...