— Copper - Density - Cu. Density of Copper is 8.92g/cm3. The density of a substance strongly depends on its atomic mass and also on the atomic number density. Skip to content. ... The bulk properties of astatine are not known with any certainty. 6.4 g/cm3. 86. Rn. Radon. 9.73 g/cm3. Radon. Discoverer: Dorn, Friedrich Ernst.