Nobelium

Atomic number

102

Atomic mass (u)

259.10100

Category

Actinide

Standard state

Solid

Melting point

826.85 °C (1100 K)

Boiling point

Not reported

Density (g/cm³)

Not reported in this source

Electronegativity (Pauling)

1.3

Electron configuration

[Rn]7s2 5f14

Oxidation states

+3, +2

Atomic radius (pm)

Not reported in this source

First ionization energy (eV)

6.65

Discovery & recognition

Discovery year / period (PubChem)

1957

Discovery credited to (RSC)

Georgy Flerov and colleagues and at Dubna, near Moscow, Russia, and independently by Albert Ghiorso and colleagues at Berkeley, California, USA

Date or period recorded by RSC

1963

Discovery place

Dubna, Russia (recognised discovery); earlier disputed claims elsewhere

An ancient date does not identify a first human discovery. Different references may date observation, isolation and formal recognition differently.

Natural occurrence & production

This transuranium element is primarily produced through nuclear reactions in reactors or particle accelerators. Some transuranium elements also occur naturally in extremely small traces; that is different from a mineable deposit.

“Nobelium is made by bombarding curium with carbon in a device called a cyclotron.”

Royal Society of Chemistry · occurrence excerpt ↗

Continue the research

Reference values are not product specifications. Blank values have not been estimated. For superheavy elements, some properties and family assignments are theoretical or incompletely measured.