Krypton-79

Properties and data of the isotope ⁷⁹Kr.

Contents

General Data

Radioactive Decay

Parent Nuclides

Isotones und Isobares

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

General data

Name of the isotope:Krypton-79; Kr-79Symbol:⁷⁹Kr or 7936KrMass number A:79 (= number of nucleons)Atomic number Z:36 (= number of protons)Neutrons N:43Nucleon pairing (Z - N):even - oddNuclear ratio (N/Z ratio):1.1944444444444 (= neutron-proton ratio)Neutron excess (N-Z):7Isotopic mass:78.920083(4) u (atomic weight of Krypton-79)Nuclide mass:78.9003349 u (calculated nuclear mass without electrons)Mass excess:-74.44221 MeVMass defect:0.73420953999999 u (per nucleus)Nuclear binding energy:683.91178125 MeV (per nucleus)
8.65711116 MeV (average binding energy per nucleon)Separation energy:S_N = 8.335(3) MeV (first neutron)
S_P = 8.279(5) MeV (first proton)Half-life:35.04(10) hDecay constant λ:5.494888227422 × 10^-6 s^-1Specific activity α:4.242434732710 × 10⁺¹⁶ Bq g^-1
1146603.9818137 Ci g^-1Spin and parity:
(nuclear angular momentum)1/2-Magnetic dipole moment:μ(μ_N) = + 0.536(2)Nuclear g-factor:g_l = 1.072Charge radius:4.2034(32) femtometer fmYear of discovery:1948

Radioactive Decay

Half-life T_½ = 35.04(10) h (hours) respectively 1.26144 × 10⁵ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
EC/β⁺	⁷⁹Br	100 %	1.626(4) MeV

Parent Nuclides

Direct parent isotope is: ⁷⁹Rb.

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
^79mKr	129.77(5) keV	50(3) s	7/2+

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 43) and isobaric (same nucleon number A = 79) with Krypton-79. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 43	Isobar A = 79
22	⁶⁵Ti
23	⁶⁶V
24	⁶⁷Cr
25	⁶⁸Mn
26	⁶⁹Fe
27	⁷⁰Co
28	⁷¹Ni	⁷⁹Ni
29	⁷²Cu	⁷⁹Cu
30	⁷³Zn	⁷⁹Zn
31	⁷⁴Ga	⁷⁹Ga
32	⁷⁵Ge	⁷⁹Ge
33	⁷⁶As	⁷⁹As
34	⁷⁷Se	⁷⁹Se
35	⁷⁸Br	⁷⁹Br
36	⁷⁹Kr	⁷⁹Kr
37	⁸⁰Rb	⁷⁹Rb
38	⁸¹Sr	⁷⁹Sr
39	⁸²Y	⁷⁹Y
40	⁸³Zr	⁷⁹Zr
41	⁸⁴Nb
42	⁸⁵Mo
43	⁸⁶Tc
44	⁸⁷Ru