Element 105
Dubnium
Transition metals
Dubnium (Db) is in the d-block of the periodic table — group 5, period 7.
Dubnium is a chemical element with symbol Db and atomic number 105.
Key data
- Atomic number
- 105
- Atomic mass
- 268.000 u
- Group / Period
- 5 / 7
- Block
- d-block
- Phase at STP
- Solid
- Density
- 29.3 g/cm³
- Melting point
- —
- Boiling point
- —
- Electron configuration
- *[Rn] 5f14 6d3 7s2
Periodic table block
Dubnium is in the d-block (group 5, period 7). Elements land in the d-block when their highest-energy electrons fill a d subshell — these are the transition metals in the middle of the table.
New to this? Periodic table blocks explained: s, p, d, and f
Common uses
- •Research only
- •Named after Dubna
- •Few atoms ever made
Discovery
Year: 1967
Discovered by: Joint Institute for Nuclear Research
Frequently asked questions
What is the atomic number of Dubnium?
Dubnium has atomic number 105. Its symbol is Db and its atomic mass is 268 u.
What category of element is Dubnium?
Dubnium is classified as transition metals. It sits in group 5, period 7 of the periodic table.
What block of the periodic table is Dubnium in?
Dubnium is in the d-block (group 5, period 7). Its highest-energy electrons occupy the d subshell — you can see this in its electron configuration, *[Rn] 5f14 6d3 7s2.
What is Dubnium used for?
Common uses of Dubnium include: Research only, Named after Dubna, Few atoms ever made.
When was Dubnium discovered?
Dubnium was discovered in 1967 by Joint Institute for Nuclear Research.
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