Atomic Number
98
Element 98
Californium (Cf)
Californium is a radioactive chemical element with symbol Cf and atomic number 98. The element was first synthesized in 1950 at the Lawrence Berkeley National Laboratory, by bombarding curium with alpha particles.
Atomic Mass
251 u
Category
Actinide
Period
7
Group
Actinide series
Phase
solid
Density
15.1 g/cm3
Electron Shells
2, 8, 18, 32, 28, 8, 2
Atomic Structure
Protons: 98. Electrons: 98. Neutrons: Varies by isotope.
Electron configuration: 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d¹⁰ 6p⁶ 7s² 5f¹⁰
Why Californium Matters
Californium helps connect atomic number 98, actinide behavior, period 7 trends, and electron shell structure. Its solid phase, atomic mass of 251 u, and electron configuration 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d¹⁰ 6p⁶ 7s² 5f¹⁰ make it useful for comparing bonding patterns across the periodic table.
Discovery and Occurrence
Californium was discovered 1950 by Stanley G. Thompson, Kenneth Street Jr., Albert Ghiorso, Glenn T. Seaborg. Californium is a radioactive chemical element with symbol Cf and atomic number 98. The element was first synthesized in 1950 at the Lawrence Berkeley National Laboratory, by bombarding curium with alpha particles.
Safety and Handling Context
Californium has radioactive isotopes or is commonly discussed with radioactive materials. Use this page as an educational reference; real samples require qualified supervision and controlled handling.
Related Elements
Frequently Asked Questions
- What is the atomic number of Californium?
- Californium has atomic number 98, which means a neutral atom has 98 protons and 98 electrons.
- What is the chemical symbol for Californium?
- The chemical symbol for Californium is Cf.
- What category is Californium in?
- Californium is classified as a actinide and sits in period 7 of the periodic table.
Explore Californium in 3D
Use the interactive table above to rotate atomic models, compare periodic trends, and move from Californium to neighboring elements without losing your place.