Krypton-70

Properties and data of the isotope ⁷⁰Kr.

Contents

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

General data

Name of the isotope:Krypton-70; Kr-70Symbol:⁷⁰Kr or 7036KrMass number A:70 (= number of nucleons)Atomic number Z:36 (= number of protons)Neutrons N:34Nucleon pairing (Z - N):even - evenNuclear ratio (N/Z ratio):0.94444444444444 (= neutron-proton ratio)Neutron excess (N-Z):-2Isotopic mass:69.95588(21) u (atomic weight of Krypton-70)Nuclide mass:69.9361319 u (calculated nuclear mass without electrons)Mass excess:-41.09752 MeVMass defect:0.62042829600001 u (per nucleus)Nuclear binding energy:577.92523515 MeV (per nucleus)
8.25607479 MeV (average binding energy per nucleon)Separation energy:S_N = 16.74(45) MeV (first neutron)
S_P = 2.13(20) MeV (first proton)Half-life:40(6) msDecay constant λ:17.328679513999 s^-1Specific activity α:1.512402158695 × 10⁺²³ Bq g^-1
4087573401880.3 Ci g^-1Spin and parity:
(nuclear angular momentum)0+Mirror nucleus:Selenium-70Year of discovery:1995

Radioactive Decay

Half-life T_½ = 40(6) ms respectively 4.0 × 10^-2 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
EC/β⁺	⁷⁰Br	98.7 %	10.33(20) MeV
EC, p	⁶⁹Se	< 1.3 %

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 34) and isobaric (same nucleon number A = 70) with Krypton-70. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 34	Isobar A = 70
17	⁵¹Cl
18	⁵²Ar
19	⁵³K
20	⁵⁴Ca
21	⁵⁵Sc
22	⁵⁶Ti
23	⁵⁷V
24	⁵⁸Cr
25	⁵⁹Mn	⁷⁰Mn
26	⁶⁰Fe	⁷⁰Fe
27	⁶¹Co	⁷⁰Co
28	⁶²Ni	⁷⁰Ni
29	⁶³Cu	⁷⁰Cu
30	⁶⁴Zn	⁷⁰Zn
31	⁶⁵Ga	⁷⁰Ga
32	⁶⁶Ge	⁷⁰Ge
33	⁶⁷As	⁷⁰As
34	⁶⁸Se	⁷⁰Se
35	⁶⁹Br	⁷⁰Br
36	⁷⁰Kr	⁷⁰Kr
37	⁷¹Rb