D

Dubnium

Db; element 105; [Rn]5f¹⁴6d³7s²; superheavy transactinide
Quick Reference
Formula / NotationDb; element 105; [Rn]5f¹⁴6d³7s²; superheavy transactinide
Also Known AsDb, element 105, hahnium (historical US name), nielsbohrium (historical)

What is Dubnium?

A synthetic radioactive transactinide element with atomic number 105 and symbol Db. It is named after Dubna, Russia, where it was first synthesized. Dubnium has no stable isotopes and its most stable known isotope has a half-life of about 28 hours.

Formula & Notation

Db; element 105; [Rn]5f¹⁴6d³7s²; superheavy transactinide

Other Names / Synonyms: Db, element 105, hahnium (historical US name), nielsbohrium (historical)

Properties & Characteristics

Dubnium (Db, element 105) is a synthetic, radioactive transactinide element in Group 5 of the periodic table, below tantalum. It was first synthesised in 1968 at both Dubna (JINR, Russia — hence the name) and Berkeley (Lawrence Berkeley National Laboratory). The most stable isotope is ²⁶⁸Db (half-life ~29 hours). Its chemistry is predicted to resemble niobium and tantalum (Group 5 congeners), forming pentavalent compounds.

Uses & Applications

Dubnium is produced only in microgram or submicrogram quantities by nuclear reactions in particle accelerators and has no practical applications outside of nuclear physics and the study of transactinide chemistry. Research focuses on testing whether relativistic effects alter expected group chemistry.

Safety Information

All isotopes of dubnium are intensely radioactive (alpha and spontaneous fission emitters) with short half-lives. Any chemical work requires hot cell facilities with remote manipulation. There are no known safe exposure levels — ALARA principles apply at all times.

Always consult the SDS/MSDS before handling any chemical. This information is for educational purposes only.

Key Facts

Term Dubnium
Formula Db; element 105; [Rn]5f¹⁴6d³7s²; superheavy transactinide
Synonyms Db, element 105, hahnium (historical US name), nielsbohrium (historical)

Frequently Asked Questions

A synthetic radioactive transactinide element with atomic number 105 and symbol Db. It is named after Dubna, Russia, where it was first synthesized. Dubnium has no stable isotopes and its most stable known isotope has a half-life of about 28 hours.

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