Americium (Am)

grundstof med atomnummer 95

Atomnummer	95
Atommasse	243
mass number	223

Gruppe
Periode	7
Blok	f

proton	95 p⁺
neutron	128 n⁰
elektron	95 e^-

Animated Bohrs atommodel of Am (Americium)

Fysisk Egenskab

Atomradius	175 pm 276 pm
molar volume	20,8 cm³/mol
Kovalent Radius	166 pm 135 pm 180 pm
Metallic Radius
Ionisk radius	121 pm 126 pm 131 pm 97,5 pm 109 pm 85 pm 95 pm 115,7 pm
Crystal Radius	135 pm 140 pm 145 pm 111,5 pm 123 pm 99 pm 109 pm 129,7 pm
Van der Waals-radius	244 pm 338,1 pm
massefylde	12 g/cm³

Kemisk Egenskab

{ERROR}

energi

proton affinity
electron affinity
ioniseringsenergi	5,9738 eV/particle 11,7 eV/particle 21,7 eV/particle 36,8 eV/particle 50 eV/particle 67,9 eV/particle 95 eV/particle 110 eV/particle 126 eV/particle 141 eV/particle 162 eV/particle 184 eV/particle 206 eV/particle 225 eV/particle 242 eV/particle 284 eV/particle 305 eV/particle 424 eV/particle 451 eV/particle 481 eV/particle 511 eV/particle 541 eV/particle 571 eV/particle 616 eV/particle 646 eV/particle 680 eV/particle 711 eV/particle 860 eV/particle 900 eV/particle 940 eV/particle 980 eV/particle 1.090 eV/particle 1.130 eV/particle 1.240 eV/particle 1.280 eV/particle 1.410 eV/particle 1.490 eV/particle 1.570 eV/particle 1.650 eV/particle 1.740 eV/particle 1.820 eV/particle 1.900 eV/particle 1.980 eV/particle 2.070 eV/particle 2.160 eV/particle 2.240 eV/particle 2.320 eV/particle 2.410 eV/particle 2.000 eV/particle 2.874 eV/particle 2.946 eV/particle 3.021 eV/particle 3.101 eV/particle 3.178 eV/particle 3.251 eV/particle 3.402 eV/particle 3.479 eV/particle 3.563 eV/particle 3.641 eV/particle 3.956 eV/particle 4.033 eV/particle 4.115 eV/particle 4.191 eV/particle 4.642 eV/particle 4.733 eV/particle 4.960 eV/particle 5.050 eV/particle 8.040 eV/particle 8.210 eV/particle 8.400 eV/particle 8.590 eV/particle 8.770 eV/particle 8.950 eV/particle 9.380 eV/particle 9.560 eV/particle 9.770 eV/particle 9.960 eV/particle 10.490 eV/particle 10.650 eV/particle 10.830 eV/particle 11.000 eV/particle 12.400 eV/particle 12.600 eV/particle 13.000 eV/particle 13.190 eV/particle 27.110 eV/particle 27.550 eV/particle 28.040 eV/particle 28.500 eV/particle 33.700 eV/particle 34.300 eV/particle 35.100 eV/particle 35.549,4 eV/particle 139.769,5 eV/particle 142.161 eV/particle

Fordampningsvarme	238,5 kJ/mol
smeltevarme	10 kJ/mol
standard enthalpy of formation	284 kJ/mol
elektron

Elektronskal	2, 8, 18, 32, 25, 8, 2

Valenselektron	2 ⓘ

electron configuration	[Rn] 5f⁷ 7s²ⓘ 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d¹⁰ 6p⁶ 5f⁷ 7s²

Oxidationstrin	2, 3, 4, 5, 6, 7
Elektronegativitet	0.17194
Electrophilicity Index
fundamental state of matter

stoffase
gaseous state of matter
Kogepunkt
Smeltepunkt	1.449,15 K
critical pressure
critical temperature
trippelpunkt
appearance
farve	Sort #ffffff #545cf2 #545cf2
appearance	silvery white
Brydningsindeks
materialeegenskab
Varmeledningsevne
Termisk ekspansion
molar heat capacity
Varmefylde
Adiabateksponenten
electrical properties
type
specifik ledningsevne
Elektrisk resistivitet
superledning	0,6 K
Magnetisme
type	paramagnetic
magnetic susceptibility (Mass)	0,0000000515 m³/Kg
magnetic susceptibility (Molar)	0,00000001251 m³/mol
magnetic susceptibility (Volume)	0,000704
magnetic ordering
Curietemperaturen
Néel temperature
struktur
Krystalstruktur	{ERROR}
lattice constant
Lattice Angles	π/2, π/2, 2 π/3
mechanical property
hårdhed
Kompressibilitetsmodul
Forskydningsmodul
E-modul
Poissons forhold
speed of sound
klassificering
Kategori	Actinider, Actinides
CAS Group
IUPAC Group
Glawe Number	39
Mendeleev Number	26
Pettifor Number	42
Geochemical Class
Goldschmidt classification	synthetic

øvrige

Gas Basicity
polarizability	131 ± 25 a₀
C6 Dispersion Coefficient
allotrope
Neutron cross section	74
Neutron Mass Absorption
quantum number	8S7/2
rumgruppe	194 (P63/mmc)

Isotopes of Americium

Stable Isotopes	0
Unstable Isotopes	27
Natural Isotopes	0

²²³Am

mass number	223
neutron number	128
Relative Atomic Mass	223,04584 ± 0,000322 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	10 ± 9 ms
spin	9/2
nuclear quadrupole moment
opdagelsesdato	2015
Paritet	-

decay mode	Intensitet
α (α emission)	100%
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)

²²⁴Am

mass number	224
neutron number	129
Relative Atomic Mass	224,046442 ± 0,000429 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid
spin
nuclear quadrupole moment
opdagelsesdato
Paritet

decay mode	Intensitet
α (α emission)
SF (spontaneous fission)

²²⁵Am

mass number	225
neutron number	130
Relative Atomic Mass	225,045508 ± 0,000429 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid
spin	9/2
nuclear quadrupole moment
opdagelsesdato
Paritet	-

decay mode	Intensitet
α (α emission)
SF (spontaneous fission)

²²⁶Am

mass number	226
neutron number	131
Relative Atomic Mass	226,04613 ± 0,000322 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid
spin
nuclear quadrupole moment
opdagelsesdato
Paritet

decay mode	Intensitet
α (α emission)
SF (spontaneous fission)

²²⁷Am

mass number	227
neutron number	132
Relative Atomic Mass	227,045282 ± 0,000215 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid
spin	9/2
nuclear quadrupole moment
opdagelsesdato
Paritet	-

decay mode	Intensitet
α (α emission)
SF (spontaneous fission)

²²⁸Am

mass number	228
neutron number	133
Relative Atomic Mass	228,046001 ± 0,000215 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid
spin
nuclear quadrupole moment
opdagelsesdato
Paritet

decay mode	Intensitet
α (α emission)
SF (spontaneous fission)

²²⁹Am

mass number	229
neutron number	134
Relative Atomic Mass	229,045282534 ± 0,000114169 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	1,8 ± 1,5 s
spin	5/2
nuclear quadrupole moment
opdagelsesdato	2015
Paritet	-

decay mode	Intensitet
α (α emission)	100%
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)

²³⁰Am

mass number	230
neutron number	135
Relative Atomic Mass	230,046025 ± 0,000153 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	40 ± 9 s
spin	1
nuclear quadrupole moment
opdagelsesdato	2003
Paritet	-

decay mode	Intensitet
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
β⁺ SF (β⁺-delayed fission)	30%

²³¹Am

mass number	231
neutron number	136
Relative Atomic Mass	231,045529 ± 0,000322 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid
spin	5/2
nuclear quadrupole moment
opdagelsesdato
Paritet	-

decay mode	Intensitet
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)
α (α emission)

²³²Am

mass number	232
neutron number	137
Relative Atomic Mass	232,046613 ± 0,000322 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	1,31 ± 0,04 m
spin	1
nuclear quadrupole moment
opdagelsesdato	1967
Paritet	-

decay mode	Intensitet
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	97%
α (α emission)
β⁺ SF (β⁺-delayed fission)	0.069%

²³³Am

mass number	233
neutron number	138
Relative Atomic Mass	233,046468 ± 0,000123 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	3,2 ± 0,8 m
spin	5/2
nuclear quadrupole moment
opdagelsesdato	2000
Paritet	-

decay mode	Intensitet
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)
α (α emission)	4.5%

²³⁴Am

mass number	234
neutron number	139
Relative Atomic Mass	234,047731 ± 0,000172 Da
g-factor	0
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	2,32 ± 0,08 m
spin	0
nuclear quadrupole moment	0
opdagelsesdato	1967
Paritet	-

decay mode	Intensitet
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
α (α emission)	0.039%
β⁺ SF (β⁺-delayed fission)	0.0066%

²³⁵Am

mass number	235
neutron number	140
Relative Atomic Mass	235,047906478 ± 0,000056661 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	10,3 ± 0,6 m
spin	5/2
nuclear quadrupole moment
opdagelsesdato	1996
Paritet	-

decay mode	Intensitet
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	99.6%
α (α emission)	0.4%

²³⁶Am

mass number	236
neutron number	141
Relative Atomic Mass	236,049427 ± 0,000127 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	3,6 ± 0,1 m
spin	5
nuclear quadrupole moment
opdagelsesdato	1998
Paritet	-

decay mode	Intensitet
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
α (α emission)	4%

²³⁷Am

mass number	237
neutron number	142
Relative Atomic Mass	237,049995 ± 0,000064 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	73,6 ± 0,8 m
spin	5/2
nuclear quadrupole moment
opdagelsesdato	1970
Paritet	-

decay mode	Intensitet
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	99.975%
α (α emission)	0.025%

²³⁸Am

mass number	238
neutron number	143
Relative Atomic Mass	238,051982531 ± 0,000063243 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	98 ± 3 m
spin	1
nuclear quadrupole moment
opdagelsesdato	1950
Paritet	+

decay mode	Intensitet
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
α (α emission)	1%

²³⁹Am

mass number	239
neutron number	144
Relative Atomic Mass	239,053022729 ± 0,000002127 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	11,9 ± 0,1 h
spin	5/2
nuclear quadrupole moment
opdagelsesdato	1949
Paritet	-

decay mode	Intensitet
ϵ (electron capture)	99.99%
α (α emission)	0.01%

²⁴⁰Am

mass number	240
neutron number	145
Relative Atomic Mass	240,055298374 ± 0,000014849 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	50,8 ± 0,3 h
spin	3
nuclear quadrupole moment
opdagelsesdato	1949
Paritet	-

decay mode	Intensitet
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
α (α emission)	1.9%

²⁴¹Am

mass number	241
neutron number	146
Relative Atomic Mass	241,056827343 ± 0,000001195 Da
g-factor	0,64 ± 0,004
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	432,6 ± 0,6 y
spin	5/2
nuclear quadrupole moment	4,34 ± 0,05
opdagelsesdato	1949
Paritet	-

decay mode	Intensitet
α (α emission)	100%
SF (spontaneous fission)	3.6%

²⁴²Am

mass number	242
neutron number	147
Relative Atomic Mass	242,059547358 ± 0,000001199 Da
g-factor	0,3854 ± 0,0017
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	16,02 ± 0,02 h
spin	1
nuclear quadrupole moment	-2,4 ± 0,4
opdagelsesdato	1949
Paritet	-

decay mode	Intensitet
β⁻ (β⁻ decay)	82.7%
ϵ (electron capture)	17.3%

²⁴³Am

mass number	243
neutron number	148
Relative Atomic Mass	243,061379889 ± 0,00000149 Da
g-factor	0,608 ± 0,004
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	7,35 ± 0,009 ky
spin	5/2
nuclear quadrupole moment	4,32 ± 0,06
opdagelsesdato	1950
Paritet	-

decay mode	Intensitet
α (α emission)	100%
SF (spontaneous fission)	3.7%

²⁴⁴Am

mass number	244
neutron number	149
Relative Atomic Mass	244,064282892 ± 0,0000016 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	10,01 ± 0,03 h
spin	6
nuclear quadrupole moment
opdagelsesdato	1950
Paritet	-

decay mode	Intensitet
β⁻ (β⁻ decay)	100%

²⁴⁵Am

mass number	245
neutron number	150
Relative Atomic Mass	245,066452827 ± 0,000002024 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	2,05 ± 0,01 h
spin	5/2
nuclear quadrupole moment
opdagelsesdato	1955
Paritet	+

decay mode	Intensitet
β⁻ (β⁻ decay)	100%

²⁴⁶Am

mass number	246
neutron number	151
Relative Atomic Mass	246,069774 ± 0,000019 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	39 ± 3 m
spin	7
nuclear quadrupole moment
opdagelsesdato	1955
Paritet	-

decay mode	Intensitet
β⁻ (β⁻ decay)	100%

²⁴⁷Am

mass number	247
neutron number	152
Relative Atomic Mass	247,072092 ± 0,000107 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	23 ± 1,3 m
spin	5/2
nuclear quadrupole moment
opdagelsesdato	1967
Paritet

decay mode	Intensitet
β⁻ (β⁻ decay)	100%

²⁴⁸Am

mass number	248
neutron number	153
Relative Atomic Mass	248,075752 ± 0,000215 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid
spin	3
nuclear quadrupole moment
opdagelsesdato
Paritet	+

decay mode	Intensitet
β⁻ (β⁻ decay)

²⁴⁹Am

mass number	249
neutron number	154
Relative Atomic Mass	249,07848 ± 0,00032 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid
spin	5/2
nuclear quadrupole moment
opdagelsesdato
Paritet

decay mode	Intensitet
β⁻ (β⁻ decay)

historie

opdager eller opfinder	G.T.Seaborg, R.A.James, L.O.Morgan, A.Ghiorso
fundsted	United States
opdagelsesdato	1945
etymologi	Named for the American continent, by analogy with europium.
udtale	am-er-ISH-i-em (engelsk)

source

Forekomst
Abundance in Earth's crust
natural abundance (verdenshave)
natural abundance (menneskelige krop)	0 %
natural abundance (Meteoroid)	0 %
natural abundance (Solen)	0 %
Abundance in Universe	0 %

Nuclear Screening Constants

Americium on ChemicalAid

Americium (Am)

Fysisk Egenskab

Kemisk Egenskab

øvrige

Isotopes of Americium

223Am

224Am

225Am

226Am

227Am

228Am

229Am

230Am

231Am

232Am

233Am

234Am

235Am

236Am

237Am

238Am

239Am

240Am

241Am

242Am

243Am

244Am

245Am

246Am

247Am

248Am

249Am

historie

source

Nuclear Screening Constants

²²³Am

²²⁴Am

²²⁵Am

²²⁶Am

²²⁷Am

²²⁸Am

²²⁹Am

²³⁰Am

²³¹Am

²³²Am

²³³Am

²³⁴Am

²³⁵Am

²³⁶Am

²³⁷Am

²³⁸Am

²³⁹Am

²⁴⁰Am

²⁴¹Am

²⁴²Am

²⁴³Am

²⁴⁴Am

²⁴⁵Am

²⁴⁶Am

²⁴⁷Am

²⁴⁸Am

²⁴⁹Am