Symbol Db
Atomic Number 105
Atomic Mass 268 g.mol -1
Discovered by Scientists at both Berkeley, California, USA, and Dubna, near Moscow, Russia between 1968-1970

Chemical Properties of Dubnium

Group 5 Melting point Unknown 
Period 7 Boiling point Unknown 
Block d Density (g cm−3) Unknown 
Atomic number 105 Relative atomic mass [268] 
State at 20°C Solid Key isotopes 268Db
Electron configuration [Rn]5f16d7s2 CAS number 53850-35-4
ChemSpider ID ChemSpider is a free chemical structure database.

What is Dubnium?

  • Dubnium is a chemical element discovered by Albert Ghiorso in the year 1970. It has an atomic number of 105 with a symbol Db, and it belongs to the 7th period of the 5th group of the periodic table.

Uses of Dubnium

  • Since Dubnium is not produced in high amounts and it does not exist even on the earth’s crust. Hence there are no such practical applications of this metal apart from the research areas.
  • The metal has not also proved any harmful effects on health and the environment since it tends to decompose within a short period.

Properties of Dubnium

  • The metal behaves as a solid at temperatures of 20o °C. It occurs as a synthetic element in nature, and it is artificially produced by the bombardment of the californium-249 with the nuclei nitrogen-1.
  • Dubnium is a highly radioactive element with only one single stable isotope dubnium-268 which has a half-life measuring about only 32 hours and gets decayed through the process of spontaneous fission. The other isotopes are synthetic in nature and have their mass numbers ranging from 256 to 270.
  • The metal is produced in small amounts artificially. The bombardment of it can make many isotopes of it with the Heavy Ion Linear Accelerator.

Practise This Question

Statement I: Glucose gives a reddish-brown precipitate with Fehling's solution. 
Statement I: Reaction of glucose with Fehling's solution gives CuO and gluconic acid. 
(IIT-JEE, 2007)