Periodic System for Chemists

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Table
105
268.00

Db

Dubnium

Identification

CAS Number: 53850-35-4
Discovery Year: 1970
Discoverer: A. Ghiorso, et al
Discovery Location: United States

Properties

Atomic Mass: 268 →Density: 29.3 g/cm³ →

Electronic Structure

Electron Config: [Rn] 5f14 6d3 7s2
Block: d
Period: 7 →Group: 5 →

Abundance & Geochemistry

Goldschmidt Class: synthetic

About

Also known as Hahnium, Ha. Radioactive transactinide element. Half-life of 1.6s. Discovered in 1970 by Berkeley researchers. So far, seven isotopes have been discovered.

Isotopes

Db-268 268 ☢ 30.8 h
Db-270 270 ☢ 90.0 h

Related Elements

Category

Transition Metals

Same Group

23 V Vanadium41 Nb Niobium73 Ta Tantalum

Same Period

102 No Nobelium103 Lr Lawrencium104 Rf Rutherfordium106 Sg Seaborgium107 Bh Bohrium108 Hs Hassium

Periodic Trends

Electronegativity →Atomic Radius →Density →Melting Point →

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