Which is the heaviest element in periodic table in terms of density?
Osmium is the heaviest element in terms of Density. Osmium is an extremely dense, blue-gray, hard but brittle metal that remains lustrous even at high temperatures. Due to its hardness, brittleness, and very high melting point (the fourth highest of all elements), solid osmium is difficult to machine, form, or work. Osmium is generally considered to be the densest known element, narrowly defeating iridium. Calculations of density from the space lattice may produce the most reliable data for these elements, giving a density of 22.562±0.009 g/cm3 for iridium versus 22.587±0.009 g/cm3 for osmium. The extraordinary density of osmium is a consequence of the lanthanide contraction.