DUBNIUM, Db (105)

Dubnium was first produced as 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 which has a half-life of 28 hours. In the 1960s and 1970s, microscopic amounts of dubnium were produced in laboratories in the former Soviet Union and in California.

ELEMENT BRIEF

1967 by Workers at the Nuclear Institute at Dubna and the University of California, Berkeley, USA.

DISCOVERY

From the name of the Joint Nuclear Institute at Dubna, an institute heavily involved in the search for heavy elements.

ETYMOLOGY

Dubnium

ELEMENT

Db

SYMBOL

105

ATOMIC NUMBER

53850-35-4

CAS NUMBER

ELEMENTAL SPECTRUM

-

ELEMENTAL COLOUR

-

REFRACTIVE INDEX

-

POISSON RATIO

9.151 cm³

MOLAR VOLUME

-

BRINELL HARDNESS

-

MOHS HARDNESS

-

VICKERS HARDNESS

-

SPEED OF SOUND

-

BULK MODULUS

-

SHEAR MODULUS

-

YOUNG MODULUS

ALLOTROPES

NONE

-

MELTING POINT

-

BOILING POINT

-

AUTOMATIC IGNITION

-

FLASHPOINT

-

CRITICAL TEMPERATURE

-

CRITICAL PRESSURE

-

THERMAL CONDUCTIVITY

-

THERMAL EXPANSION

-

SPECIFIC HEAT

-

HEAT FUSION

-

HEAT VAPORISATION

-

HEAT COMBUSTION

-

CURIE POINT

-

NEEL POINT

-

ADIABATIC INDEX

Solid

PHASE

-

ELECTRICAL TYPE

-

CONDUCTIVITY

-

RESISTIVITY

-

SUPERCONDUCTING POINT

-

MAGNETIC TYPE

-

MASS SUSCEPTIBILITY

-

MOLAR SUSCEPTIBILITY

-

VOLUME SUSCEPTIBILITY

Transition Metal

CLASSIFICATION

268.125'670'0

ATOMIC WEIGHT

-

ATOMIC RADIUS

149 pm

COVALENT RADIUS SINGLE BOND

136 pm

COVALENT RADIUS DOUBLE BOND

126 pm

COVALENT RADIUS TRIPLE BOND

139 pm

VAN DER WAALS RADIUS

[Rn]7s²5f¹⁴7p³

ELECTRON CONFIGURATION

Cubic, Body-centred

CRYSTAL STRUCTURE

29.300'00 g/cm³

DENSITY AS SOLID

-

DENSITY AS LIQUID

-

DENSITY AS GAS

-

SPACE GROUP NAME

-

SPACE GROUP NUMBER

-

LATTICE ANGLES

-

LATTICE CONSTANTS

5

VALENCE

-

ELECTRONEGATIVITY

-

ELECTRON AFFINITY

IONISATION ENERGY