Nobelium-250m

Properties and data of the isotope ^250mNo.

Contents

See also: List of individual Nobelium isotopes (and general data sources).

General data

Name of the isotope:Nobelium-250m; No-250mSymbol:^250mNo or 250m102NoMass number A:250 (= number of nucleons)Atomic number Z:102 (= number of protons)Neutrons N:148Nucleon pairing (Z - N):even - evenNuclear ratio (N/Z ratio):1.4509803921569 (= neutron-proton ratio)Neutron excess (N-Z):46Excitation energy:1050 keVIsotopic mass:250.08756(21) u (atomic weight of Nobelium-250m)Nuclide mass:250.0316133 u (calculated nuclear mass without electrons)Mass excess:81.56161 MeVMass defect:1.993000832 u (per nucleus)Nuclear binding energy:1856.468317 MeV (per nucleus)
7.42587327 MeV (average binding energy per nucleon)Half-life:46 μsDecay constant λ:15068.416968694 s^-1Specific activity α:3.629765180869 × 10⁺²⁵ Bq g^-1
9.810176164512 × 10⁺¹⁴ Ci g^-1Spin and parity:
(nuclear angular momentum)(6+)

Radioactive Decay

Half-life T_½ = 46 μs respectively 4.6 × 10^-5 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
SZ	div	ca. 100 %

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
²⁵⁰No		4.2 μs	0+

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 148) and isobaric (same nucleon number A = 250) with Nobelium-250m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 148	Isobar A = 250
90	²³⁸Th
91	²³⁹Pa
92	²⁴⁰U
93	²⁴¹Np
94	²⁴²Pu
95	²⁴³Am
96	²⁴⁴Cm	²⁵⁰Cm
97	²⁴⁵Bk	²⁵⁰Bk
98	²⁴⁶Cf	²⁵⁰Cf
99	²⁴⁷Es	²⁵⁰Es
100	²⁴⁸Fm	²⁵⁰Fm
101	²⁴⁹Md	²⁵⁰Md
102	²⁵⁰No	²⁵⁰No
103	²⁵¹Lr
104	²⁵²Rf