Stable isotope Einsteinium (Es)

Isotope Atomic Mass Half-life Mode of Decay Nuclear Spin Nuclear Magnetic Moment
Es-249 249.07640 1.70 hours  EC to Cf-249; α to Bk-245  7/2 No data available
Es-250 250.0787 8.60 hours  EC to Cf-250; α to Bk-246  6 No data available
Es-251 251.07998 1.38 days  EC to Cf-251; α to Bk-247  3/2 No data available
Es-252 252.082944 1.29 years  EC to Cf-252; α to Bk-248; ß- to Fm-252  5 No data available
Es-253 253.08482 20.47 days  α to Bk-249; SF  7/2 4.10
Es-254 254.08802 276 days  EC to Cf-254; α to Bk-250; ß- to Fm-254; SF  7 No data available
Es-255 255.09027 40 days  α to Bk-251; ß- to Fm-255; SF  7/2 No data available

Properties of Einsteinium

Name Einsteinium
Symbol Es
Atomic number 99
Atomic weight [252]
Standard state Solid at 298 °K
CAS Registry ID 7429-92-7
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 1133 °K [or 860 °C or 1580 °F]
Boiling point No data available
Density of solid 13.50 g/cm3
Electron configuration [Rn]5f117s2