Cf
Californium · element 98
Actinide · Solid at room temperature
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).
Key facts
Atomic mass
251 u
how heavy one atom is
Phase (room temp.)
Solid
Density
15.1 g/cm³
how tightly packed it is
Melting point
1173 K (900 °C)
when solid turns to liquid
Boiling point
1743 K (1470 °C)
when liquid turns to gas
Period
7
its row in the periodic table
Group
3
its column in the periodic table
Block
F-block
the neighbourhood it lives in
Electronegativity
1.3
how strongly it pulls electrons
Electron configuration
[Rn] 5f10 7s2
where its electrons live
Shells
2 · 8 · 18 · 32 · 28 · 8 · 2
electrons in each layer, inside to out
Discovered by
Lawrence Berkeley National Laboratory
who found it
Appearance
silvery
what it looks like
Source: Wikipedia