Ar

Argon

Z 18 39.95 g/molNoble Gas

Overview Atomic Properties Thermodynamics Electromagnetism Isotopes


⁴⁰Ar	22	39.9624	-35,039.9	99.6035%	Stable	0+	---	1920
³⁶Ar	18	35.9675	-30,231.542	0.3336%	Stable	0+	β⁺	1920
³⁸Ar	20	37.9627	-34,714.83	0.0629%	Stable	0+	---	1934
²⁹Ar	11	29.0408	37,970.0	---	---	(5/2+)	p²⁷S(100%)	2018
³⁰Ar	12	30.0237	22,070.0	---	---	0+	p²⁸S(100%)	2015
³¹Ar	13	31.0122	11,330.0	---	15.0 ms	5/2+	β⁺p³⁰S(68.3%) β⁺³¹Cl(22.63%) β⁺p²⁹P(9%) β⁺pα(<0.38%) β⁺p(0.07%) β⁺α²⁷P(<0.03%) p²⁹S(<0.001%)	1986
³²Ar	14	31.9976	-2,200.4	---	98.0 ms	0+	β⁺³²Cl(64.42%) β⁺p³¹S(35.58%)	1977
³³Ar	15	32.9899	-9,384.3	---	173.0 ms	1/2+	β⁺³³Cl(61.3%) β⁺p³²S(38.7%)	1964
³⁴Ar	16	33.9803	-18,378.29	---	846.46 ms	0+	β⁺³⁴Cl(100%)	1966
³⁵Ar	17	34.9753	-23,047.3	---	1.78 s	3/2+	β⁺³⁵Cl(100%)	1940
³⁷Ar	19	36.9668	-30,947.68	---	35.01 d	3/2+	EC³⁷Cl(100%)	1941
³⁹Ar	21	38.9643	-33,242.0	---	268.0 y	7/2-	β⁻³⁹K(100%)	1950
⁴¹Ar	23	40.9645	-33,067.5	---	1.83 h	7/2-	β⁻⁴¹K(100%)	1936
⁴²Ar	24	41.963	-34,423.0	---	32.9 y	0+	β⁻⁴²K(100%)	1952
⁴³Ar	25	42.9656	-32,010.0	---	5.37 m	(5/2-)	β⁻⁴³K(100%)	1969
⁴⁴Ar	26	43.9649	-32,673.3	---	11.87 m	0+	β⁻⁴⁴K(100%)	1969
⁴⁵Ar	27	44.968	-29,770.8	---	21.48 s	(5/2-)	β⁻⁴⁵K(100%)	1974
⁴⁶Ar	28	45.968	-29,771.3	---	8.4 s	0+	β⁻⁴⁶K(100%)	1974
⁴⁷Ar	29	46.9728	-25,367.3	---	1.23 s	(3/2-)	β⁻⁴⁷K(~100%) β⁻n⁴⁶K(<0.2%)	1985
⁴⁸Ar	30	47.976	-22,355.0	---	415.0 ms	0+	β⁻⁴⁸K(62%) β⁻n⁴⁷K(38%)	2004
⁴⁹Ar	31	48.9817	-17,060.0	---	236.0 ms	(3/2-)	β⁻⁴⁹K(71%) β⁻n⁴⁸K(29%) β⁻n⁴⁷K	1989
⁵⁰Ar	32	49.9858	-13,230.0	---	106.0 ms	0+	β⁻⁵⁰K(63%) β⁻n⁴⁹K(37%) β⁻n⁴⁸K	1989
⁵¹Ar	33	50.993	-6,490.0	---	30.0 ms	(1/2-)	β⁻⁵¹K β⁻n⁵⁰K β⁻n⁴⁹K	1989
⁵²Ar	34	51.9985	-1,380.0	---	40.0 ms	0+	β⁻⁵²K β⁻n⁵¹K β⁻n⁵⁰K	2009
⁵³Ar	35	53.0073	6,790.0	---	20.0 ms	(5/2-)	β⁻⁵³K β⁻n⁵²K β⁻n⁵¹K	2009
⁵⁴Ar	36	54.0135	12,560.0	---	5.0 ms	0+	β⁻⁵⁴K β⁻n⁵³K β⁻n⁵²K	2018