Radon-200

Properties and data of the isotope ²⁰⁰Rn.

Contents

General Data

Radioactive Decay

Parent Nuclides

Isotones und Isobares

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

General data

Name of the isotope:Radon-200; Rn-200Symbol:²⁰⁰Rn or 20086RnMass number A:200 (= number of nucleons)Atomic number Z:86 (= number of protons)Neutrons N:114Nucleon pairing (Z - N):even - evenNuclear ratio (N/Z ratio):1.3255813953488 (= neutron-proton ratio)Neutron excess (N-Z):28Isotopic mass:199.995701(15) u (atomic weight of Radon-200)Nuclide mass:199.9485288 u (calculated nuclear mass without electrons)Mass excess:-4.00449 MeVMass defect:1.665052176 u (per nucleus)Nuclear binding energy:1550.98611163 MeV (per nucleus)
7.75493056 MeV (average binding energy per nucleon)Separation energy:S_N = 10.58(4) MeV (first neutron)
S_P = 2.470(15) MeV (first proton)Half-life:ca. 1.03 sDecay constant λ:0.6729584277281 s^-1Specific activity α:2.036507761135 × 10⁺²¹ Bq g^-1
55040750300.968 Ci g^-1Spin and parity:
(nuclear angular momentum)0+Year of discovery:1971

Radioactive Decay

Half-life T_½ = ca. 1.03 s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
α	¹⁹⁶Po	ca. 86 %	7.0434(21) MeV
EC/β⁺	²⁰⁰At	ca. 14 %	4.983(28) MeV

Parent Nuclides

Direct parent isotope is: ²⁰⁴Ra.

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
^200mRn	2300.5(5)+x	25 μs

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 114) and isobaric (same nucleon number A = 200) with Radon-200. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 114	Isobar A = 200
70	¹⁸⁴Yb
71	¹⁸⁵Lu
72	¹⁸⁶Hf
73	¹⁸⁷Ta
74	¹⁸⁸W
75	¹⁸⁹Re
76	¹⁹⁰Os	²⁰⁰Os
77	¹⁹¹Ir	²⁰⁰Ir
78	¹⁹²Pt	²⁰⁰Pt
79	¹⁹³Au	²⁰⁰Au
80	¹⁹⁴Hg	²⁰⁰Hg
81	¹⁹⁵Tl	²⁰⁰Tl
82	¹⁹⁶Pb	²⁰⁰Pb
83	¹⁹⁷Bi	²⁰⁰Bi
84	¹⁹⁸Po	²⁰⁰Po
85	¹⁹⁹At	²⁰⁰At
86	²⁰⁰Rn	²⁰⁰Rn
87	²⁰¹Fr	²⁰⁰Fr
88	²⁰²Ra
89	²⁰³Ac