Potassium-35

Properties and data of the isotope ³⁵K.

Contents

General Data

Radioactive Decay

Parent Nuclides

Isotones und Isobares

Literature

Potassium-35 is a radioisotope of the chemical element potassium, which has 16 neutrons in its atomic nucleus in addition to the element-specific 19 protons; the sum of the number of these atomic nucleus building blocks results in a mass number of 35.

The radioactive isotope was discovered - according to a report from 1976 [1] - during the irradiation of a calcium-48 template with helium-3 nuclei of an energy of 73.7 and 75.8 MeV:

⁴⁸Ca(³He,⁸Li)³⁵K.

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

General data

Name of the isotope:Potassium-35; K-35Symbol:³⁵K or 3519KMass number A:35 (= number of nucleons)Atomic number Z:19 (= number of protons)Neutrons N:16Nucleon pairing (Z - N):odd - evenNuclear ratio (N/Z ratio):0.84210526315789 (= neutron-proton ratio)Neutron excess (N-Z):-3Isotopic mass:34.9880054(6) u (atomic weight of Potassium-35)Nuclide mass:34.9775826 u (calculated nuclear mass without electrons)Mass excess:-11.1729 MeVMass defect:0.299308864 u (per nucleus)Nuclear binding energy:278.80441096 MeV (per nucleus)
7.96584031 MeV (average binding energy per nucleon)Separation energy:S_N = 18.024(196) MeV (first neutron)
S_P = 0.0836(5) MeV (first proton)Half-life:178(8) msDecay constant λ:3.8940852840446 s^-1Specific activity α:6.89727355915 × 10⁺²² Bq g^-1
1864127988960.5 Ci g^-1Spin and parity:
(nuclear angular momentum)(3/2)+Magnetic dipole moment:μ(μ_N) = +0.392(7)Nuclear g-factor:g_l = 0.26133333333333Mirror nucleus:Sulfur-35Year of discovery:1976

Radioactive Decay

Half-life T_½ = 178(8) ms respectively 1.78 × 10^-1 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β⁺;	³⁵Ar	99.63(15) %	11.8744(9) MeV
β⁺, p;	³⁴Cl	0.37(15) %	5.982 MeV

Parent Nuclides

Direct parent isotope is: ³⁵Ca.

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 16) and isobaric (same nucleon number A = 35) with Potassium-35. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 16	Isobar A = 35
5	²¹B
6	²²C
7	²³N
8	²⁴O
9	²⁵F
10	²⁶Ne
11	²⁷Na	³⁵Na
12	²⁸Mg	³⁵Mg
13	²⁹Al	³⁵Al
14	³⁰Si	³⁵Si
15	³¹P	³⁵P
16	³²S	³⁵S
17	³³Cl	³⁵Cl
18	³⁴Ar	³⁵Ar
19	³⁵K	³⁵K
20	³⁶Ca	³⁵Ca
21	³⁷Sc
22	³⁸Ti

External data and identifiers

Adopted Levels, Gammas:NuDat 35K

Literature and References

[1] - W. Benenson, A. Guichard, E. Kashy, D. Mueller, H. Nann:
Mass of ³⁵K.
In: Physical Review C, 13, 1479, (1976), DOI 10.1103/PhysRevC.13.1479.

[2] - S. I. Sukhoruchkin, Z. N. Soroko:
Energy levels for K-35 (Potassium-35).
In: Landolt-Börnstein - Group I Elementary Particles, Nuclei and Atoms, (2008), DOI 10.1007/978-3-540-75278-3_113.