Roentgenium

Symbol: Rg

Category(transition metal)

Density at 25°C: solid:  n/a

For a heavy element at this end of the periodic table it has a slightly longer half life of about 26 seconds. Compared with the previous element of darmstadtium at 11 seconds.  Named after Wilhelm Conrad Röntgen, the discoverer of X-rays, it doesn't actually emit x-rays.  Only a few atoms have been produced as result of colliding bismuth atoms with nickel atoms.