98
Cf
251
Californium (Cf)
Element 98 · Period 7 · Actinide series
actinide
solid at room temp
f-block
radioactive
synthetic
About Californium
Strong neutron emitter. Used in nuclear startup rods and cancer treatment.
Physical Properties
Atomic Mass
251 u
State at 25°C
Solid
Melting Point
900 °C
Density
15.1 g/cm³
Magnetism
Paramagnetic
Atomic Properties
Electron Configuration
[Rn] 5f¹⁰ 7s²
Electron Shells
2, 8, 18, 32, 28, 8, 2
Electronegativity
1.3
Atomic Radius
245 pm
Ionization Energy
608 kJ/mol
Oxidation States
+3
Discovery & History
Discovered By
Glenn T. Seaborg
Discovery Year
1950
Named By
Glenn T. Seaborg
Name origin: California
Frequently Asked Questions
- Is Californium a metal, nonmetal, or metalloid?
- Californium is classified as a actinide.
- What state is Californium in at room temperature?
- Californium is a solid at standard room temperature (25°C).
- What is the atomic mass of Californium?
- Californium has an atomic mass of 251 atomic mass units (u).
- Who discovered Californium?
- Californium was discovered by Glenn T. Seaborg in 1950.
- Where is Californium on the periodic table?
- Californium is element number 98, located in period 7, part of the actinide series shown below the main table.