Dubnium Facts

Dubnium or Db Chemical & Physical Properties

Dubnium is a superheavy radioactive manmade element.
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by Anne Marie Helmenstine, Ph.D.
Dr. Helmenstine holds a Ph.D. in biomedical sciences and is a science writer, educator, and consultant. She has taught science courses at the high school, college, and graduate levels.
Updated February 26, 2018

Dubnium is a radioactive synthetic element. Here are interesting facts about this element and a summary of its chemical and physical properties.

Interesting Dubnium Facts

  • Dubnium is named for the town in Russia where it was first made, Dubna. It may only be produced in a nuclear facility. Dubnium does not exist naturally on Earth.
  • The element dubnium was the subject of a naming controversy. The Russian discovery team (1969) proposed the name nielsbohrium (Ns) in honor of the Danish nuclear physicist Niels Bohr. In 1970, an American team made the element by bombarding californium-239 with nitrogen-15 atoms. They proposed the name hahnium (Ha), to honor the Nobel Prize winning chemist Otto Hahn. The IUPAC determined the two labs should share credit for the discovery because their results supported each other's validity, using different methods to create the element. The IUPAC assigned the name unnilpentium for element 105 until a naming decision could be reached. It wasn't until 1997 it was decided the element should be named Dubnium (Db) for the Dubna research facility -- the location where the element was initially synthesized.
  • Dubnium is a super-heavy or transactinide element. If a sufficient amount were ever produced, its chemical properties are expected to be similar to that of the transition metals. It would be most similar to the element tantalum.
  • Dubnium was first made by bombarding americium-243 with neon-22 atoms.
  • All isotopes of dubnium are radioactive. The most stable one has a half-life of 28 hours.
  • Only a few atoms of dubnium have ever been produced. At present, little is known about its properties and it has no practical uses.

Dubnium or Db Chemical and Physical Properties

Element Name: Dubnium

Atomic Number: 105

Symbol: Db

Atomic Weight: (262)

Discovery: A. Ghiorso, et al, L Berkeley Lab, USA - G.N. Flerov, Dubna Lab, Russia 1967

Discovery Date: 1967 (USSR); 1970 (United States)

Electron Configuration: [Rn] 5f14 6d3 7s2

Element Classification: Transition Metal

Crystal Structure: body centered cubic

Name Origin: Joint Institute for Nuclear Research at Dubna

Appearance: Radioactive, synthetic metal

References: Los Alamos National Laboratory (2001), Crescent Chemical Company (2001), Lange's Handbook of Chemistry (1952)