Protactinium-232

Properties and data of the isotope ²³²Pa.

Contents

General Data

Radioactive Decay

Parent Nuclides

Isotones und Isobares

See also: list of Protactinium isotopes.

General data

Name of the isotope:Protactinium-232; Pa-232Symbol:²³²Pa or 23291PaMass number A:232 (= number of nucleons)Atomic number Z:91 (= number of protons)Neutrons N:141Isotopic mass:232.038590(8) u (atomic weight of Protactinium-232)Nuclide mass:231.9886757 u (calculated nuclear mass without electrons)Mass excess:35.94635 MeVMass defect:1.895241068 u (per nucleus)Nuclear binding energy:1765.4056834 MeV (per nucleus)
7.60950726 MeV (average binding energy per nucleon)Separation energy:S_N = 5.549(8) MeV (first neutron)
S_P = 5.158(8) MeV (first proton)Half-life:1.32(2) dDecay constant λ:6.077679403057 × 10^-6 s^-1Specific activity α:1.577613856325 × 10⁺¹⁶ Bq g^-1
426382.12333122 Ci g^-1Spin and parity:
(nuclear angular momentum)(2-)Year of discovery:1949

Radioactive Decay

Half-life T_½ = 1.32(2) d respectively 1.14048 × 10⁵ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β^-	²³²U	ca. 100 %	1.337(7) MeV
EC	²³²Th	?	0.500(8) MeV

Parent Nuclides

Direct parent isotope is: ²³⁶Np.

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 141) and isobaric (same nucleon number A = 232) with Protactinium-232. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 141	Isobar A = 232
83	²²⁴Bi
84	²²⁵Po
85	²²⁶At
86	²²⁷Rn
87	²²⁸Fr	²³²Fr
88	²²⁹Ra	²³²Ra
89	²³⁰Ac	²³²Ac
90	²³¹Th	²³²Th
91	²³²Pa	²³²Pa
92	²³³U	²³²U
93	²³⁴Np	²³²Np
94	²³⁵Pu	²³²Pu
95	²³⁶Am	²³²Am
96	²³⁷Cm	²³²Cm
97	²³⁸Bk
98	²³⁹Cf
99	²⁴⁰Es
100	²⁴¹Fm