Chromium-50

Properties and data of the isotope ⁵⁰Cr.

Contents

General Data

Radioactive Decay

Parent Nuclides

Isotones und Isobares

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

General data

Name of the isotope:Chromium-50; Cr-50Symbol:⁵⁰Cr or 5024CrMass number A:50 (= number of nucleons)Atomic number Z:24 (= number of protons)Neutrons N:26Nucleon pairing (Z - N):even - evenNuclear ratio (N/Z ratio):1.0833333333333 (= neutron-proton ratio)Neutron excess (N-Z):2Isotopic mass:49.9460414(5) u (atomic weight of Chromium-50)Nuclide mass:49.9328758 u (calculated nuclear mass without electrons)Mass excess:-50.26211 MeVMass defect:0.467047184 u (per nucleus)Nuclear binding energy:435.05164961 MeV (per nucleus)
8.70103299 MeV (average binding energy per nucleon)Separation energy:S_N = 13.0003(22) MeV (first neutron)
S_P = 8.5891(9) MeV (first proton)Half-life:1.3 × 10¹⁸ aDecay constant λ:1.690726591116 × 10^-26 s^-1Specific activity α:0.00020779170790496 Bq g^-1
5.615992105539 × 10^-15 Ci g^-1Spin and parity:
(nuclear angular momentum)0+Isobaric spin: 1Charge radius:3.6588(65) femtometer fmMirror nucleus:Iron-50Year of discovery:1930

Radioactive Decay

Half-life T_½ = 1.3 × 10¹⁸ a respectively 4.0997 × 10²⁵ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
2 EC ?

Parent Nuclides

Direct parent isotopes are: ⁵⁰Mn, ⁵⁰V.

Occurrence

Comparison of the natural Chromium isotopes including isotopic abundance (mole fraction of the isotope mixture in percent):

	Atomic Mass m_a	Quantity	Half-life	Spin
Chromium Isotopic mixture	51.9961 u	100 %
Isotope ⁵⁰Cr	49.9460414(5) u	4.345(13) %	1.3 × 10¹⁸ a	0+
Isotope ⁵²Cr	51.940506(4) u	83.789(18) %	stable	0+
Isotope ⁵⁴Cr	53.938879(4) u	2.365(7) %	stable	0+
Isotope ⁵³Cr	52.94064630(12) u	9.501(17) %	stable	3/2-

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 26) and isobaric (same nucleon number A = 50) with Chromium-50. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 26	Isobar A = 50
11	³⁷Na
12	³⁸Mg
13	³⁹Al
14	⁴⁰Si
15	⁴¹P
16	⁴²S
17	⁴³Cl	⁵⁰Cl
18	⁴⁴Ar	⁵⁰Ar
19	⁴⁵K	⁵⁰K
20	⁴⁶Ca	⁵⁰Ca
21	⁴⁷Sc	⁵⁰Sc
22	⁴⁸Ti	⁵⁰Ti
23	⁴⁹V	⁵⁰V
24	⁵⁰Cr	⁵⁰Cr
25	⁵¹Mn	⁵⁰Mn
26	⁵²Fe	⁵⁰Fe
27	⁵³Co	⁵⁰Co
28	⁵⁴Ni	⁵⁰Ni
29	⁵⁵Cu
30	⁵⁶Zn