98Cf251.07959
Californium
Actinide
Solid at STP
Period 7Block FDiscovered 1950
[Rn]7s2 5f10
Californium is a radioactive metallic chemical element with symbol Cf and atomic number 98. The element was first made in 1950 at the University of California Radiation Laboratory in Berkeley, by bombarding curium with alpha particles (helium-4 ions). It is an actinide element, the sixth transuranium element to be synthesized, and has the second-highest atomic mass of all the elements that have been produced in amounts large enough to see with the unaided eye (after einsteinium).
📖 Read more on Wikipedia →Atomic Properties
| Atomic Number | 98 |
| Atomic Mass | 251.07959 u |
| Electron Configuration | [Rn]7s2 5f10 |
| Oxidation States | +3 |
| Electronegativity | 1.3 (Pauling) |
| Atomic Radius | 245 pm |
| Ionization Energy | 6.3 eV |
| Block | F |
Physical Properties
| Appearance | silvery |
| Standard State | Solid |
| Melting Point | 1173 K (899.9 °C) |
| CPK Color | #A136D4 |
Classification
| Category | Actinide |
| Group Block | Actinide |
| Period | 7 |
| Block | F |
Discovery
| Year Discovered | 1950 |
| Discovered By | Lawrence Berkeley National Laboratory |
| Electron Shells | 2, 8, 18, 32, 28, 8, 2 |