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: 623.35
Density        636.36 g/cm^3.
Melting Point: 85.434
Boiling Point: 64.43