Bk
Berkelium
Element 97 · Actinide
Berkelium (Bk)
Berkelium is a radioactive metal made only in tiny amounts in high-flux nuclear reactors.
- Actinide
- Period 7
- f-block series
- f-block
- solid at room temperature
- ☢ Radioactive
Key properties
- Atomic mass
- [247]
- u
- Electron configuration
- [Rn] 5f9 7s2
- Melting point
- 1,049.9 °C
- 1,323 K
- Boiling point
- 2,626.9 °C
- 2,900 K
- Density
- 14 g/cm³
- Electronegativity
- 1.3
- Pauling
- Atomic radius
- 244 pm
- van der Waals
- 1st ionisation energy
- 6.23 eV
Compare with every element:Electronegativity chartAtomic radius chartIonisation energy chartDensity chart of the elementsMelting point chartElectron configuration chart
Did you know?
Notable facts about berkelium
- 01
Since 1967 the United States has made only around a gram of berkelium in total.
- 02
Berkelium-249 was the target used to create tennessine, element 117.
- 03
Its first weighable sample was not made until nine years after its discovery.
Applications
What is berkelium used for?
- Production of heavier elements
- Research
History
Discovery & name origin
Discovered by
Year
Where
United States
Name origin
From Berkeley, California.
Atomic structure
Atomic properties
Atomic structure
Atomic properties
- Atomic number
- 97
- Atomic mass
- [247] u
- Group
- Actinides (3)
- Period
- 7
- Block
- f-block
- Electron configuration
- [Rn] 5f9 7s2
- Full configuration
- 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 5f9
- Electrons per shell
- 2, 8, 18, 32, 27, 8, 2
- Electronegativity (Pauling)
- 1.3
- Electron affinity
- —
- Atomic radius (van der Waals)
- 244 pm
- Stable isotopes
- None — all isotopes are radioactive
Oxidation states
Highlighted: common oxidation states (+4, +3).
Physical
Physical properties & colour
Physical
Physical properties & colour
- State at 20 °C
- Solid
- Melting point
- 1,323 K · 1,049.9 °C · 1,921.7 °F
- Boiling point
- 2,900 K · 2,626.9 °C · 4,760.3 °F
- Density
- 14 g/cm³
- Molar heat capacity
- —
- Appearance
- Silvery
- CPK model colour
- Copied
The CPK colour is the convention used for this element’s atoms in molecular models.
FAQ
Berkelium questions
What is Bk on the periodic table?
Bk is the symbol for berkelium, element 97 on the periodic table. It sits in period 7, in the f-block, in the actinide category, and has an atomic mass of [247].
What is the atomic number of berkelium?
Berkelium has atomic number 97, so every berkelium atom has 97 protons in its nucleus. Its symbol is Bk and its atomic mass is [247].
Who discovered berkelium?
Berkelium was discovered by Stanley G. Thompson, Albert Ghiorso and Glenn T. Seaborg in 1949 (United States). The name comes from from Berkeley, California.
What is berkelium used for?
Berkelium is used for: production of heavier elements; research.
Is berkelium a metal?
Yes. Berkelium is a actinide, one of the metallic elements.
What is the electron configuration of berkelium?
The electron configuration of berkelium is [Rn] 5f9 7s2. Its 97 electrons are arranged in shells as 2, 8, 18, 32, 27, 8, 2.