Californium

Koushik 26/06/2026 19:58:09 Updated 26/06/2026 19:58:09

Property	Value
Atomic Number	98
Element	Californium
Symbol	Cf
Atomic Mass	[251] (most stable isotope)
Number of Neutrons	153 (Californium-251)
Number of Protons	98
Number of Electrons	98
Period	7
Group	Actinide (no fixed group number)
Phase	Solid
Radioactive	Yes
Natural	No (synthetic element)
Metal	Yes
Nonmetal	No
Metalloid	No
Type	Actinide
Atomic Radius	~186 pm (estimated)
Electronegativity	1.30 (estimated)
First Ionization Energy	6.281 eV (estimated)
Density	15.10 g/cm³ (estimated)
Melting Point	900 °C
Boiling Point	~1470 °C (estimated)
Number of Isotopes	No stable isotopes (Cf-251, Cf-252 most notable)
Discoverer	Glenn T. Seaborg, Stanley G. Thompson, Kenneth Street Jr., Albert Ghiorso
Year	1950
Specific Heat	— (not well established)
Number of Shells	7
Number of Valence Electrons	3