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105Db268.000
Dubnium
Transition MetalDubnium is a chemical element with symbol Db and atomic number 105. It is named after the town of Dubna in Russia (north of Moscow), where it was first produced. It is a synthetic element (an element that can be created in a laboratory but is not found in nature) and radioactive; the most stable known isotope, dubnium-268, has a half-life of approximately 28 hours.
Phase: Solid
2, 8, 18, 32, 32, 11, 2
Physical Properties
Atomic Mass268 u
Density29.3 g/cm³
Period7
PhaseSolid
Chemical Properties
Electron Configuration1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 5f14 6d3
Semantic Config*[Rn] 5f14 6d3 7s2
Shells2, 8, 18, 32, 32, 11, 2
Discovery
Discovered byJoint Institute for Nuclear Research