Stable isotope Rutherfordium (Rf)

Isotope Atomic Mass Half-life Mode of Decay
Rf-255 255.1015 1.70 seconds α to No-251; SF
Rf-256 256.1012 0.007 seconds α to No-252; SF
Rf-257 257.1032 4.70 seconds α to No-253; SF; EC to Lr-257
Rf-258 258.1035 0.012 seconds α to No-254; SF
Rf-259 259.1056 3.40 seconds α to No-255; SF; EC to Lr-259
Rf-260 260.1065 0.020 seconds α to No-256; SF
Rf-261 261.10869 1.10 minutes α to No-257; SF; EC to Lr-261
Rf-262 262.1101 1.20 seconds SF
Rf-263 263.1125 15.00 minutes α to No-259; SF

Properties of Rutherfordium

Name Rutherfordium
Symbol Rf
Atomic number 104
Atomic weight [265]
Standard state Presumably a solid at 298 °K
CAS Registry ID 53850-36-5
Group in periodic table 4
Group name None
Period in periodic table 7
Block in periodic table d-block
Color Unknown, but probably metallic and silvery white or grey in appearance
Classification Metallic
Melting point No data available
Boiling point No data available
Density of solid 17.00 g/cm3 (predicted)
Electron configuration [Rn}5f146d27s2