Dubnium is a synthetic chemical element with symbol Db and atomic number 105. Dubnium is highly radioactive: the most stable known isotope, dubnium-268, has a half-life of just over a day. This greatly limits the extent of research on dubnium.

Atomic Weight:  2323
Density:        3434 g/cm3
Melting Point:  45.6 °C
 Boiling Point: 34 °C