Stable isotope Nobelium (No)

Isotope Atomic Mass Half-life Mode of Decay Nuclear Spin
No-253 253.0907 1.70 minutes α to Fm-249; EC to Md-253 9/2
No-254 254.0909 55 seconds α to Fm-250; EC to Md-254; SF 0
No-255 255.0932 3.10 minutes α to Fm-251; EC to Md-255 1/2
No-256 256.0943 2.90 seconds α to Fm-252; AS 0
No-257 257.0968 25 seconds α to Fm-253 7/2
No-258 258.0983 0.0012 seconds α to Fm-254; SF 0

Properties of Nobelium

Name Nobelium
Symbol No
Atomic number 102
Atomic weight [259]
Standard state Presumably a solid at 298 °K
CAS Registry ID 10028-14-5
Group in periodic table N/A
Group name Actinoid
Period in periodic table 7 (Actinoid)
Block in periodic table f-block
Color Unknown, but probably metallic and silvery white or grey in appearance
Classification Metallic
Melting point About 1100 °K [or 827 °C or 1521 °F]
Boiling point No data available
Electron configuration [Rn]5f147s2