Fermium (Fm)

grundstof med atomnummer 100

Atomnummer	100
Atommasse	257
mass number	241

Gruppe
Periode	7
Blok	f

proton	100 p⁺
neutron	141 n⁰
elektron	100 e^-

Animated Bohrs atommodel of Fm (Fermium)

Fysisk Egenskab

Atomradius
molar volume
Kovalent Radius	167 pm
Metallic Radius
Ionisk radius	110,5 pm
Crystal Radius	124,5 pm
Van der Waals-radius	245 pm 328,6 pm
massefylde	9,7 g/cm³

Kemisk Egenskab

{ERROR}

energi

proton affinity
electron affinity
ioniseringsenergi	6,5 eV/particle 10 eV/particle 23,2 eV/particle 39,3 eV/particle 55 eV/particle 74 eV/particle 93 eV/particle 120 eV/particle 136 eV/particle 162 eV/particle 185 eV/particle 209 eV/particle 237 eV/particle 257 eV/particle 276 eV/particle 300 eV/particle 326 eV/particle 351 eV/particle 377 eV/particle 402 eV/particle 430 eV/particle 453 eV/particle 616 eV/particle 647 eV/particle 680 eV/particle 716 eV/particle 749 eV/particle 782 eV/particle 837 eV/particle 871 eV/particle 909 eV/particle 944 eV/particle 1.110 eV/particle 1.150 eV/particle 1.190 eV/particle 1.230 eV/particle 1.370 eV/particle 1.420 eV/particle 1.550 eV/particle 1.600 eV/particle 1.770 eV/particle 1.860 eV/particle 1.940 eV/particle 2.030 eV/particle 2.120 eV/particle 2.210 eV/particle 2.300 eV/particle 2.390 eV/particle 2.490 eV/particle 2.590 eV/particle 2.680 eV/particle 2.760 eV/particle 2.900 eV/particle 2.950 eV/particle 3.403 eV/particle 3.480 eV/particle 3.561 eV/particle 3.647 eV/particle 3.730 eV/particle 3.810 eV/particle 3.986 eV/particle 4.070 eV/particle 4.160 eV/particle 4.245 eV/particle 4.586 eV/particle 4.670 eV/particle 4.760 eV/particle 4.840 eV/particle 5.420 eV/particle 5.510 eV/particle 5.760 eV/particle 5.860 eV/particle 9.200 eV/particle 9.370 eV/particle 9.570 eV/particle 9.770 eV/particle 9.970 eV/particle 10.160 eV/particle 10.660 eV/particle 10.860 eV/particle 11.080 eV/particle 11.280 eV/particle 11.850 eV/particle 12.020 eV/particle 12.220 eV/particle 12.390 eV/particle 14.180 eV/particle 14.400 eV/particle 14.800 eV/particle 15.000 eV/particle 30.300 eV/particle 30.800 eV/particle 31.300 eV/particle 31.800 eV/particle 38.400 eV/particle 39.100 eV/particle 40.000 eV/particle 40.482,2 eV/particle 158.152,5 eV/particle 160.804 eV/particle

Fordampningsvarme
smeltevarme
standard enthalpy of formation
elektron

Elektronskal	2, 8, 18, 32, 30, 8, 2

Valenselektron	2 ⓘ

electron configuration	[Rn] 5f¹² 7s²ⓘ 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d¹⁰ 6p⁶ 5f¹² 7s²

Oxidationstrin	2, 3
Elektronegativitet	0.22485
Electrophilicity Index
fundamental state of matter

stoffase
gaseous state of matter
Kogepunkt
Smeltepunkt	1.800,15 K
critical pressure
critical temperature
trippelpunkt
appearance
farve	Sort #ffffff #b31fba #b31fba
appearance
Brydningsindeks
materialeegenskab
Varmeledningsevne
Termisk ekspansion
molar heat capacity
Varmefylde
Adiabateksponenten
electrical properties
type
specifik ledningsevne
Elektrisk resistivitet
superledning
Magnetisme
type
magnetic susceptibility (Mass)
magnetic susceptibility (Molar)
magnetic susceptibility (Volume)
magnetic ordering
Curietemperaturen
Néel temperature
struktur
Krystalstruktur	{ERROR}
lattice constant
Lattice Angles
mechanical property
hårdhed
Kompressibilitetsmodul
Forskydningsmodul
E-modul
Poissons forhold
speed of sound
klassificering
Kategori	Actinider, Actinides
CAS Group
IUPAC Group
Glawe Number	44
Mendeleev Number	36
Pettifor Number	37
Geochemical Class
Goldschmidt classification	synthetic

øvrige

Gas Basicity
polarizability	113 ± 20 a₀
C6 Dispersion Coefficient
allotrope
Neutron cross section	5.800
Neutron Mass Absorption
quantum number	3H6
rumgruppe	()

Isotopes of Fermium

Stable Isotopes	0
Unstable Isotopes	20
Natural Isotopes	0

²⁴¹Fm

mass number	241
neutron number	141
Relative Atomic Mass	241,074311 ± 0,000322 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	730 ± 60 us
spin	5/2
nuclear quadrupole moment
opdagelsesdato	2008
Paritet	+

decay mode	Intensitet
SF (spontaneous fission)
α (α emission)	14%
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	12%

²⁴²Fm

mass number	242
neutron number	142
Relative Atomic Mass	242,07343 ± 0,00043 Da
g-factor	0
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	800 ± 200 us
spin	0
nuclear quadrupole moment	0
opdagelsesdato	1975
Paritet	+

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

²⁴³Fm

mass number	243
neutron number	143
Relative Atomic Mass	243,074414 ± 0,00014 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	231 ± 9 ms
spin	7/2
nuclear quadrupole moment
opdagelsesdato	1981
Paritet	-

decay mode	Intensitet
α (α emission)	91%
SF (spontaneous fission)	9%
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)

²⁴⁴Fm

mass number	244
neutron number	144
Relative Atomic Mass	244,074036 ± 0,000216 Da
g-factor	0
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	3,12 ± 0,08 ms
spin	0
nuclear quadrupole moment	0
opdagelsesdato	1967
Paritet	+

decay mode	Intensitet
SF (spontaneous fission)	97%
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	2%
α (α emission)	1%

²⁴⁵Fm

mass number	245
neutron number	145
Relative Atomic Mass	245,075354 ± 0,00021 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	4,2 ± 1,3 s
spin	1/2
nuclear quadrupole moment	0
opdagelsesdato	1967
Paritet	+

decay mode	Intensitet
α (α emission)	100%
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	7%
SF (spontaneous fission)	0.3%

²⁴⁶Fm

mass number	246
neutron number	146
Relative Atomic Mass	246,075353334 ± 0,000014675 Da
g-factor	0
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	1,54 ± 0,04 s
spin	0
nuclear quadrupole moment	0
opdagelsesdato	1966
Paritet	+

decay mode	Intensitet
α (α emission)	93.2%
SF (spontaneous fission)	6.8%
ϵ (electron capture)	1.3%

²⁴⁷Fm

mass number	247
neutron number	147
Relative Atomic Mass	247,076944 ± 0,000194 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	31 ± 1 s
spin	7/2
nuclear quadrupole moment
opdagelsesdato	1967
Paritet	+

decay mode	Intensitet
α (α emission)	64%
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)

²⁴⁸Fm

mass number	248
neutron number	148
Relative Atomic Mass	248,077185451 ± 0,000009122 Da
g-factor	0
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	34,5 ± 1,2 s
spin	0
nuclear quadrupole moment	0
opdagelsesdato	1958
Paritet	+

decay mode	Intensitet
α (α emission)	100%
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)
SF (spontaneous fission)	0.1%

²⁴⁹Fm

mass number	249
neutron number	149
Relative Atomic Mass	249,078926042 ± 0,000006668 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	1,6 ± 0,1 m
spin	7/2
nuclear quadrupole moment
opdagelsesdato	1960
Paritet	+

decay mode	Intensitet
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)
α (α emission)	33%

²⁵⁰Fm

mass number	250
neutron number	150
Relative Atomic Mass	250,079519765 ± 0,000008468 Da
g-factor	0
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	31 ± 1,1 m
spin	0
nuclear quadrupole moment	0
opdagelsesdato	1954
Paritet	+

decay mode	Intensitet
α (α emission)	100%
SF (spontaneous fission)	0.0069%
ϵ (electron capture)

²⁵¹Fm

mass number	251
neutron number	151
Relative Atomic Mass	251,08154513 ± 0,000015342 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	5,3 ± 0,08 h
spin	9/2
nuclear quadrupole moment
opdagelsesdato	1957
Paritet	-

decay mode	Intensitet
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	98.2%
α (α emission)	1.8%

²⁵²Fm

mass number	252
neutron number	152
Relative Atomic Mass	252,082466019 ± 0,000005604 Da
g-factor	0
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	25,39 ± 0,04 h
spin	0
nuclear quadrupole moment	0
opdagelsesdato	1956
Paritet	+

decay mode	Intensitet
α (α emission)	100%
SF (spontaneous fission)	0.0023%
2β⁺ (double β⁺ decay)

²⁵³Fm

mass number	253
neutron number	153
Relative Atomic Mass	253,085180945 ± 0,000001662 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	3 ± 0,12 d
spin	1/2
nuclear quadrupole moment	0
opdagelsesdato	1957
Paritet	+

decay mode	Intensitet
ϵ (electron capture)	88%
α (α emission)	12%

²⁵⁴Fm

mass number	254
neutron number	154
Relative Atomic Mass	254,086852424 ± 0,000001978 Da
g-factor	0
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	3,24 ± 0,002 h
spin	0
nuclear quadrupole moment	0
opdagelsesdato	1954
Paritet	+

decay mode	Intensitet
α (α emission)	99.9408%
SF (spontaneous fission)	0.0592%

²⁵⁵Fm

mass number	255
neutron number	155
Relative Atomic Mass	255,089963495 ± 0,000004223 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	20,07 ± 0,07 h
spin	7/2
nuclear quadrupole moment
opdagelsesdato	1954
Paritet	+

decay mode	Intensitet
α (α emission)	100%
SF (spontaneous fission)	2.4%

²⁵⁶Fm

mass number	256
neutron number	156
Relative Atomic Mass	256,091771699 ± 0,000003241 Da
g-factor	0
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	157,1 ± 1,3 m
spin	0
nuclear quadrupole moment	0
opdagelsesdato	1955
Paritet	+

decay mode	Intensitet
SF (spontaneous fission)	91.9%
α (α emission)	8.1%

²⁵⁷Fm

mass number	257
neutron number	157
Relative Atomic Mass	257,095105419 ± 0,000004669 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	100,5 ± 0,2 d
spin	9/2
nuclear quadrupole moment
opdagelsesdato	1964
Paritet	+

decay mode	Intensitet
α (α emission)	99.79%
SF (spontaneous fission)	0.21%

²⁵⁸Fm

mass number	258
neutron number	158
Relative Atomic Mass	258,097077 ± 0,000215 Da
g-factor	0
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	370 ± 14 us
spin	0
nuclear quadrupole moment	0
opdagelsesdato	1971
Paritet	+

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

²⁵⁹Fm

mass number	259
neutron number	159
Relative Atomic Mass	259,100596 ± 0,000304 Da
g-factor
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid	1,5 ± 0,2 s
spin
nuclear quadrupole moment
opdagelsesdato	1980
Paritet

decay mode	Intensitet
SF (spontaneous fission)	100%

²⁶⁰Fm

mass number	260
neutron number	160
Relative Atomic Mass	260,102809 ± 0,000467 Da
g-factor	0
natural abundance
radioaktivitet	☢️ radioactive element
halveringstid
spin	0
nuclear quadrupole moment	0
opdagelsesdato
Paritet	+

decay mode	Intensitet
SF (spontaneous fission)

historie

opdager eller opfinder	Argonne, Los Alamos, U of Calif
fundsted	United States
opdagelsesdato	1953
etymologi	Named in honor of the scientist Enrico Fermi.
udtale	FER-mi-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

Fermium on ChemicalAid

Fermium (Fm)

Fysisk Egenskab

Kemisk Egenskab

øvrige

Isotopes of Fermium

241Fm

242Fm

243Fm

244Fm

245Fm

246Fm

247Fm

248Fm

249Fm

250Fm

251Fm

252Fm

253Fm

254Fm

255Fm

256Fm

257Fm

258Fm

259Fm

260Fm

historie

source

Nuclear Screening Constants

²⁴¹Fm

²⁴²Fm

²⁴³Fm

²⁴⁴Fm

²⁴⁵Fm

²⁴⁶Fm

²⁴⁷Fm

²⁴⁸Fm

²⁴⁹Fm

²⁵⁰Fm

²⁵¹Fm

²⁵²Fm

²⁵³Fm

²⁵⁴Fm

²⁵⁵Fm

²⁵⁶Fm

²⁵⁷Fm

²⁵⁸Fm

²⁵⁹Fm

²⁶⁰Fm