Berkelium-250

Properties and data of the isotope ²⁵⁰Bk.

Content

General data

Name of the isotope:Berkelium-250; Bk-250Symbol:²⁵⁰Bk or 25097BkMass number A:250 (= number of nucleons)Atomic number Z:97 (= number of protons)Neutrons N:153Isotopic mass:250.078315(4) u (atomic weight of Berkelium-250)Nuclide mass:250.0251103 u (calculated nuclear mass without electrons)Mass excess:72.94995 MeVMass defect:2.006445252 u (per nucleus)Nuclear binding energy:1868.99171357 MeV (per nucleus)
7.47596685 MeV (average binding energy per nucleon)Separation energy:S_N = 4.968(4) MeV (first neutron)
S_P = 5.090(4) MeV (first proton)Half-life:3.212(5) hDecay constant λ:5.994527203666 × 10^-5 s^-1Specific activity α:1.443995488368 × 10⁺¹⁷ Bq g^-1
3902690.509103 Ci g^-1Spin and parity:
(nuclear angular momentum)2-Year of discovery:1954

Radioactive Decay

Half-life T_½ = 3.212(5) h (hours) respectively 1.1563 × 10⁴ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β^-	²⁵⁰Cf	100 %	1.780(3) MeV

Parent Nuclides

Direct parent isotope is: ²⁵⁴Es.

Nuclear Isomers

Nuclear isomers or excited states with the activation energy in keV related to the ground state.

Nuclear Isomer	Excitation Energy	Half-life	Spin
^250m1Bk	35.59 keV	29(1) μs	(4+)
^250m2Bk	86(2) keV	213(8) μs	(7+)

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 153) and isobaric (same nucleon number A = 250) with Berkelium-250. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 153	Isobar A = 250
94	²⁴⁷Pu
95	²⁴⁸Am
96	²⁴⁹Cm	²⁵⁰Cm
97	²⁵⁰Bk	²⁵⁰Bk
98	²⁵¹Cf	²⁵⁰Cf
99	²⁵²Es	²⁵⁰Es
100	²⁵³Fm	²⁵⁰Fm
101	²⁵⁴Md	²⁵⁰Md
102	²⁵⁵No	²⁵⁰No
103	²⁵⁶Lr
104	²⁵⁷Rf
105	²⁵⁸Db
106	²⁵⁹Sg
107	²⁶⁰Bh