Uranium-235m1

Properties and data of the isotope ^235mU.

Contents

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

General data

Name of the isotope:Uranium-235m1; U-235mSymbol:^235mU or 235m92UMass number A:235 (= number of nucleons)Atomic number Z:92 (= number of protons)Neutrons N:143Nucleon pairing (Z - N):even - oddNuclear ratio (N/Z ratio):1.554347826087 (= neutron-proton ratio)Neutron excess (N-Z):51Excitation energy:0.0760(4) keVIsotopic mass:235.04393(2) u (atomic weight of Uranium-235m1)Nuclide mass:234.9934673 u (calculated nuclear mass without electrons)Mass excess:40.92053 MeVMass defect:1.915055932 u (per nucleus)Nuclear binding energy:1783.86311032 MeV (per nucleus)
7.59090685 MeV (average binding energy per nucleon)Half-life:ca. 26 minDecay constant λ:0.00044432511574355 s^-1Specific activity α:1.138633376432 × 10⁺¹⁸ Bq g^-1
30773875.038705 Ci g^-1Spin and parity:
(nuclear angular momentum)1/2+

Radioactive Decay

Half-life T_½ = ca. 26 min (minutes) respectively 1.560 × 10³ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
Iso	²³⁵U	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
²³⁵U		7.04(1) × 10⁸ a	7/2-
^235m2U	2500(300) keV	3.6(19) ms

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 143) and isobaric (same nucleon number A = 235) with Uranium-235m1. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 143	Isobar A = 235
84	²²⁷Po
85	²²⁸At
86	²²⁹Rn
87	²³⁰Fr
88	²³¹Ra
89	²³²Ac	²³⁵Ac
90	²³³Th	²³⁵Th
91	²³⁴Pa	²³⁵Pa
92	²³⁵U	²³⁵U
93	²³⁶Np	²³⁵Np
94	²³⁷Pu	²³⁵Pu
95	²³⁸Am	²³⁵Am
96	²³⁹Cm	²³⁵Cm
97	²⁴⁰Bk	²³⁵Bk
98	²⁴¹Cf
99	²⁴²Es
100	²⁴³Fm
101	²⁴⁴Md