Argon-32

Properties and data of the isotope ³²Ar.

Content

General data

Name of the isotope:Argon-32; Ar-32Symbol:³²Ar or 3218ArMass number A:32 (= number of nucleons)Atomic number Z:18 (= number of protons)Neutrons N:14Isotopic mass:31.9976378(19) u (atomic weight of Argon-32)Nuclide mass:31.9877635 u (calculated nuclear mass without electrons)Mass excess:-2.20038 MeVMass defect:0.2645216 u (per nucleus)Nuclear binding energy:246.40028327 MeV (per nucleus)
7.70000885 MeV (average binding energy per nucleon)Separation energy:S_N = 21.60(20) MeV (first neutron)
S_P = 2.455(4) MeV (first proton)Half-life:98(2) msDecay constant λ:7.072930413877 s^-1Specific activity α:1.374005911125 × 10⁺²³ Bq g^-1
3713529489528.9 Ci g^-1Spin and parity:
(nuclear angular momentum)0+Charge radius:3.3468(62) femtometer fmMirror nucleus:Silicon-32Year of discovery:1977

Radioactive Decay

Half-life T_½ = 98(2) ms respectively 9.8 × 10^-2 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
EE/β⁺	³²Cl	64.42(22) %	11.13475 MeV
ε, p	³¹S	35.58(22) %	9.555 MeV

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 14) and isobaric (same nucleon number A = 32) with Argon-32. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

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