Californium (Cf)
Californium (Cf, element 98) is an actinide in period 7. Atomic mass 251, electron configuration [Rn] 5f¹⁰ 7s², uses and facts.
About Californium
Californium is an actinide with the symbol Cf and atomic number 98. It is a solid at room temperature, and it sits in period 7 of the periodic table. Californium was discovered in 1950 by Glenn Seaborg.
Californium key facts
- Atomic number: 98
- Symbol: Cf
- Atomic mass: 251 u
- Category: actinide
- Group: none (f-block)
- Period: 7
- State at room temperature: solid
- Electron configuration: [Rn] 5f¹⁰ 7s²
- Electronegativity (Pauling): 1.3
- Melting point: 1173 K (899.85 °C)
- Boiling point: 1743 K (1469.85 °C)
- Density: 15.1 g/cm³
- Common oxidation states: +2, +3, +4
Electron configuration
The electron configuration of californium is [Rn] 5f¹⁰ 7s². The part in brackets is the noble gas core; the rest shows how the outer electrons fill their subshells.
Uses of californium
- Nuclear reactor startup
- Cancer treatment
- Metal detection
Did you know?
Californium-252 is used to start nuclear reactors and is one of the most expensive substances on Earth (~$27M/gram).
Neighbouring elements
- Berkelium (Bk)
- Einsteinium (Es)
- Actinium (Ac)
- Thorium (Th)
- Protactinium (Pa)
- Uranium (U)
- Neptunium (Np)
- Plutonium (Pu)
- Americium (Am)
- Curium (Cm)
Frequently asked questions
What is the atomic number of californium?
The atomic number of californium is 98, which means every californium atom has 98 protons.
What is the electron configuration of californium?
The electron configuration of californium is [Rn] 5f¹⁰ 7s².
What group and period is californium in?
Californium is an actinide in period 7.
What state is californium at room temperature?
Californium is a solid at room temperature.
What is californium used for?
Californium is used for nuclear reactor startup, cancer treatment, metal detection.