Periodic System for Chemists

Your periodic table, always with you.

Use it offline. Find elements quickly. Keep favorites and personal notes on iPhone and iPad.

Table
98
251.00

Cf

Californium

Identification

CAS Number: 7440-71-3
Discovery Year: 1950
Discoverer: G.T.Seaborg, S.G.Tompson, A.Ghiorso, K.Street Jr.
Discovery Location: United States

Properties

Atomic Mass: 251 →Density: 15.1 g/cm³ →

Atomic Dimensions

Van der Waals Radius: 245.00000000000003 pm

Thermodynamics

Melting Point: 900 K →
Heat of Formation: 196 kJ/mol

Electronic Structure

Electron Config: [Rn] 5f10 7s2
Block: f
Period: 7 →
Oxidation States: +3, +4

Abundance & Geochemistry

Goldschmidt Class: synthetic

About

Radioactive metallic transuranic element. Belongs to actinoid series. Cf-251 has a half life of about 700 years. Nine isotopes are known. Cf-252 is an intense Neutron source, which makes it an intense Neutron source and gives it a use in Neutron activation analysis and a possible use as a radiation source in medicine. First produced by Glenn T. Seaborg and associates in 1950.

Isotopes

Cf-249 249 ☢ 351 a
Cf-250 250 ☢ 13.1 a
Cf-251 251 ☢ 900 a
Cf-252 252 ☢ 2.65 a

Related Elements

Category

Actinides

Same Period

95 Am Americium96 Cm Curium97 Bk Berkelium99 Es Einsteinium100 Fm Fermium101 Md Mendelevium

Periodic Trends

Electronegativity →Atomic Radius →Density →Melting Point →

iPhone & iPad

Your periodic table, always with you.

  • Access element data offline, in the lab or in class.
  • Find elements quickly by name, symbol, or atomic number.
  • Save favorite elements and add your own notes.
Published App Store screenshots: periodic table, element details, and search (English).