Praseodymium-122

Properties and data of the isotope ¹²²Pr.

Content

See also: list of Praseodymium isotopes.

General data

Name of the isotope:Praseodymium-122; Pr-122Symbol:¹²²Pr or 12259PrMass number A:122 (= number of nucleons)Atomic number Z:59 (= number of protons)Neutrons N:63Isotopic mass:121.95181(54) u (atomic weight of Praseodymium-122)Nuclide mass:121.9194462 u (calculated nuclear mass without electrons)Mass excess:-44.8887 MeVMass defect:1.055756596 u (per nucleus)Nuclear binding energy:983.43093463 MeV (per nucleus)
8.0609093 MeV (average binding energy per nucleon)Half-life:500~ msDecay constant λ:1.3862943611199 s^-1Specific activity α:6.899553649586 × 10⁺²¹ Bq g^-1
186474422961.81 Ci g^-1Spin and parity:
(nuclear angular momentum)

Radioactive Decay

Half-life T_½ = 500~ ms respectively 5.0 × 10^-1 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β⁺	¹²²Ce

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 63) and isobaric (same nucleon number A = 122) with Praseodymium-122. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 63	Isobar A = 122
35	⁹⁸Br
36	⁹⁹Kr
37	¹⁰⁰Rb
38	¹⁰¹Sr
39	¹⁰²Y
40	¹⁰³Zr
41	¹⁰⁴Nb
42	¹⁰⁵Mo
43	¹⁰⁶Tc
44	¹⁰⁷Ru	¹²²Ru
45	¹⁰⁸Rh	¹²²Rh
46	¹⁰⁹Pd	¹²²Pd
47	¹¹⁰Ag	¹²²Ag
48	¹¹¹Cd	¹²²Cd
49	¹¹²In	¹²²In
50	¹¹³Sn	¹²²Sn
51	¹¹⁴Sb	¹²²Sb
52	¹¹⁵Te	¹²²Te
53	¹¹⁶I	¹²²I
54	¹¹⁷Xe	¹²²Xe
55	¹¹⁸Cs	¹²²Cs
56	¹¹⁹Ba	¹²²Ba
57	¹²⁰La	¹²²La
58	¹²¹Ce	¹²²Ce
59	¹²²Pr	¹²²Pr