Chemical element · Atomic number 98

Californium

Californium in the periodic table: atomic number 98, electron configuration, atomic mass, physical data, oxidation states, media credit and visible sources.

Cf

Actinide

solid

[251.07959] u

Data-based representation, not a photograph
98CfCalifornium

A locally stored, license-verified sample photograph has not been curated yet.

Data visualization for Californium — not a photograph of an element sample.

Atomic classification

Californium in the Bohr shell modelThis shows the electron distribution of the neutral atom in a simplified shell model.: 2 · 8 · 18 · 32 · 28 · 8 · 2

Shell occupancy

Californium in the Bohr shell model

This shows the electron distribution of the neutral atom in a simplified shell model.

K · n=1
2 electrons
L · n=2
8 electrons
M · n=3
18 electrons
N · n=4
32 electrons
O · n=5
28 electrons
P · n=6
8 electrons
Q · n=7
2 electrons
Shell occupancy is derived from the versioned PubChem electron configuration. Dot angles are schematic and do not represent orbitals.
Electron configuration
[Rn]7s2 5f10
Electrons per shell
2 · 8 · 18 · 32 · 28 · 8 · 2
Group
not reported
Period
7
Block
F
Element category
Actinide

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Physical and chemical properties

Atomic mass
[251.07959] u
Standard state
solid
Density
not reported
Melting point
1,173 K
Boiling point
not reported
Electronegativity
1.3 (Pauling)
First ionisation energy
6.3 eV
Oxidation states
+3
Discovery
1950

Safety and periodic classification

Safety

Safe handling cannot be inferred from Californium's position in the periodic table alone. Laboratory, classroom and disposal decisions must follow the documentation for the exact material and its safety data sheet.

Position and comparison

Californium is in period 7 and the F block. Its direct neighbours by atomic number are Berkelium and Einsteinium. The recorded Pauling electronegativity is 1.3. Periodic trends are compared only through the separately sourced neighbouring values.

Sources and scope

PubChem attributes element data to sources including IUPAC, NIST and IAEA. Quanta stores the referenced snapshot locally and leaves unknown values unavailable.