Fermium

Fermium (Fm)

grundämne
Atomnummer100
Atommassa257
masstal241
Grupp
Period7
Blockf
Protoner100 p+
Neutroner141 n0
Electrons100 e-
Animated Bohrs atommodell of Fm (Fermium)

Egenskaper

fysisk egenskap
atomradie
molvolym
kovalent radie
167 pm
Metallic Radius
ionic radius
110,5 pm
Crystal Radius
124,5 pm
Van der Waalsradie
245 pm
densitet
9,7 g/cm³
energi
proton affinity
Elektronaffinitet
joniseringsenergi
joniseringsenergi of Fm (Fermium)
ångbildningsvärme
smältvärme
Bildningsentalpi
Electrons
electron shell2, 8, 18, 32, 30, 8, 2
Bohrs atommodell: Fm (Fermium)
valenselektron2
Elektronformel: Fm (Fermium)
elektronkonfiguration[Rn] 5f12 7s2
Enhanced Bohrs atommodell of Fm (Fermium)
Orbital Diagram of Fm (Fermium)
oxidationstal2, 3
elektronegativitet
Electrophilicity
Phases
aggregationstillståndFast
Gas Phase
Kokpunkt
Smältpunkt
1 800,15 K
critical pressure
critical temperature
trippelpunkt
Visual
färg
Färglös
appearance
Brytningsindex
materialegenskap
Värmeledningsförmåga
termisk expansion
molar heat capacity
Specifik värmekapacitet
heat capacity ratio
electrical properties
type
elektrisk konduktivitet
resistivitet
supraledare
magnetism
type
magnetisk susceptibilitet (Mass)
magnetisk susceptibilitet (Molar)
magnetisk susceptibilitet (Volume)
magnetic ordering
Curiepunkten
Néel temperature
Structure
Kristallstruktur ()
Gitterkonstant
Lattice Angles
mekanisk materialegenskap
hårdhet
Kompressibilitet
skjuvmodul
Young's modulus
Poissons konstant
ljudhastighet
klassificering
KategoriAktinider, Actinides
CAS Group
IUPAC Group
Glawe Number44
Mendeleev Number36
Pettifor Number37
Geochemical Class
Goldschmidt classificationsynthetic
övrigt
Gas Basicity
Dipole Polarizability
113 ± 20 a₀
C6 Dispersion Coefficient
Allotropes
Träffyta
5 800
Neutron Mass Absorption
kvanttal3H6
rymdgrupp ()

Fermiumisotoper

Stabila isotoper0
Instabila isotoper20
Radioactive Isotopes20

241Fm

natural abundanceRadioactive ☢️
relative atomic mass
241,074311 ± 0,000322 Da
masstal241
g-factor
Halveringstid
730 ± 60 us
Spinn5/2
nuclear quadrupole moment
upptäcktsdatum2008
Paritet+

241Fm Decay Modes
decay modeIntensitet
SF (spontaneous fission)%
α (α emission)14%
β+ (β+ decay; β+ = ϵ + e+)12%

242Fm

natural abundanceRadioactive ☢️
relative atomic mass
242,07343 ± 0,00043 Da
masstal242
g-factor
0
Halveringstid
800 ± 200 us
Spinn0
nuclear quadrupole moment
0
upptäcktsdatum1975
Paritet+

242Fm Decay Modes
decay modeIntensitet
SF (spontaneous fission)100%
α (α emission)%

243Fm

natural abundanceRadioactive ☢️
relative atomic mass
243,074414 ± 0,00014 Da
masstal243
g-factor
Halveringstid
231 ± 9 ms
Spinn7/2
nuclear quadrupole moment
upptäcktsdatum1981
Paritet-

243Fm Decay Modes
decay modeIntensitet
α (α emission)91%
SF (spontaneous fission)9%
β+ (β+ decay; β+ = ϵ + e+)%

244Fm

natural abundanceRadioactive ☢️
relative atomic mass
244,074036 ± 0,000216 Da
masstal244
g-factor
0
Halveringstid
3,12 ± 0,08 ms
Spinn0
nuclear quadrupole moment
0
upptäcktsdatum1967
Paritet+

244Fm Decay Modes
decay modeIntensitet
SF (spontaneous fission)97%
β+ (β+ decay; β+ = ϵ + e+)2%
α (α emission)1%

245Fm

natural abundanceRadioactive ☢️
relative atomic mass
245,075354 ± 0,00021 Da
masstal245
g-factor
Halveringstid
4,2 ± 1,3 s
Spinn1/2
nuclear quadrupole moment
0
upptäcktsdatum1967
Paritet+

245Fm Decay Modes
decay modeIntensitet
α (α emission)100%
β+ (β+ decay; β+ = ϵ + e+)7%
SF (spontaneous fission)0.3%

246Fm

natural abundanceRadioactive ☢️
relative atomic mass
246,075353334 ± 0,000014675 Da
masstal246
g-factor
0
Halveringstid
1,54 ± 0,04 s
Spinn0
nuclear quadrupole moment
0
upptäcktsdatum1966
Paritet+

246Fm Decay Modes
decay modeIntensitet
α (α emission)93.2%
SF (spontaneous fission)6.8%
ϵ (electron capture)1.3%

247Fm

natural abundanceRadioactive ☢️
relative atomic mass
247,076944 ± 0,000194 Da
masstal247
g-factor
Halveringstid
31 ± 1 s
Spinn7/2
nuclear quadrupole moment
upptäcktsdatum1967
Paritet+

247Fm Decay Modes
decay modeIntensitet
α (α emission)64%
β+ (β+ decay; β+ = ϵ + e+)%

248Fm

natural abundanceRadioactive ☢️
relative atomic mass
248,077185451 ± 0,000009122 Da
masstal248
g-factor
0
Halveringstid
34,5 ± 1,2 s
Spinn0
nuclear quadrupole moment
0
upptäcktsdatum1958
Paritet+

248Fm Decay Modes
decay modeIntensitet
α (α emission)100%
β+ (β+ decay; β+ = ϵ + e+)%
SF (spontaneous fission)0.1%

249Fm

natural abundanceRadioactive ☢️
relative atomic mass
249,078926042 ± 0,000006668 Da
masstal249
g-factor
Halveringstid
1,6 ± 0,1 m
Spinn7/2
nuclear quadrupole moment
upptäcktsdatum1960
Paritet+

249Fm Decay Modes
decay modeIntensitet
β+ (β+ decay; β+ = ϵ + e+)%
α (α emission)33%

250Fm

natural abundanceRadioactive ☢️
relative atomic mass
250,079519765 ± 0,000008468 Da
masstal250
g-factor
0
Halveringstid
31 ± 1,1 m
Spinn0
nuclear quadrupole moment
0
upptäcktsdatum1954
Paritet+

250Fm Decay Modes
decay modeIntensitet
α (α emission)100%
SF (spontaneous fission)0.0069%
ϵ (electron capture)%

251Fm

natural abundanceRadioactive ☢️
relative atomic mass
251,08154513 ± 0,000015342 Da
masstal251
g-factor
Halveringstid
5,3 ± 0,08 h
Spinn9/2
nuclear quadrupole moment
upptäcktsdatum1957
Paritet-

251Fm Decay Modes
decay modeIntensitet
β+ (β+ decay; β+ = ϵ + e+)98.2%
α (α emission)1.8%

252Fm

natural abundanceRadioactive ☢️
relative atomic mass
252,082466019 ± 0,000005604 Da
masstal252
g-factor
0
Halveringstid
25,39 ± 0,04 h
Spinn0
nuclear quadrupole moment
0
upptäcktsdatum1956
Paritet+

252Fm Decay Modes
decay modeIntensitet
α (α emission)100%
SF (spontaneous fission)0.0023%
+ (double β+ decay)%

253Fm

natural abundanceRadioactive ☢️
relative atomic mass
253,085180945 ± 0,000001662 Da
masstal253
g-factor
Halveringstid
3 ± 0,12 d
Spinn1/2
nuclear quadrupole moment
0
upptäcktsdatum1957
Paritet+

253Fm Decay Modes
decay modeIntensitet
ϵ (electron capture)88%
α (α emission)12%

254Fm

natural abundanceRadioactive ☢️
relative atomic mass
254,086852424 ± 0,000001978 Da
masstal254
g-factor
0
Halveringstid
3,24 ± 0,002 h
Spinn0
nuclear quadrupole moment
0
upptäcktsdatum1954
Paritet+

254Fm Decay Modes
decay modeIntensitet
α (α emission)99.9408%
SF (spontaneous fission)0.0592%

255Fm

natural abundanceRadioactive ☢️
relative atomic mass
255,089963495 ± 0,000004223 Da
masstal255
g-factor
Halveringstid
20,07 ± 0,07 h
Spinn7/2
nuclear quadrupole moment
upptäcktsdatum1954
Paritet+

255Fm Decay Modes
decay modeIntensitet
α (α emission)100%
SF (spontaneous fission)2.4%

256Fm

natural abundanceRadioactive ☢️
relative atomic mass
256,091771699 ± 0,000003241 Da
masstal256
g-factor
0
Halveringstid
157,1 ± 1,3 m
Spinn0
nuclear quadrupole moment
0
upptäcktsdatum1955
Paritet+

256Fm Decay Modes
decay modeIntensitet
SF (spontaneous fission)91.9%
α (α emission)8.1%

257Fm

natural abundanceRadioactive ☢️
relative atomic mass
257,095105419 ± 0,000004669 Da
masstal257
g-factor
Halveringstid
100,5 ± 0,2 d
Spinn9/2
nuclear quadrupole moment
upptäcktsdatum1964
Paritet+

257Fm Decay Modes
decay modeIntensitet
α (α emission)99.79%
SF (spontaneous fission)0.21%

258Fm

natural abundanceRadioactive ☢️
relative atomic mass
258,097077 ± 0,000215 Da
masstal258
g-factor
0
Halveringstid
370 ± 14 us
Spinn0
nuclear quadrupole moment
0
upptäcktsdatum1971
Paritet+

258Fm Decay Modes
decay modeIntensitet
SF (spontaneous fission)100%
α (α emission)%

259Fm

natural abundanceRadioactive ☢️
relative atomic mass
259,100596 ± 0,000304 Da
masstal259
g-factor
Halveringstid
1,5 ± 0,2 s
Spinn
nuclear quadrupole moment
upptäcktsdatum1980
Paritet

259Fm Decay Modes
decay modeIntensitet
SF (spontaneous fission)100%

260Fm

natural abundanceRadioactive ☢️
relative atomic mass
260,102809 ± 0,000467 Da
masstal260
g-factor
0
Halveringstid
Spinn0
nuclear quadrupole moment
0
upptäcktsdatum
Paritet+

260Fm Decay Modes
decay modeIntensitet
SF (spontaneous fission)%
Fermium-Ytterbium Alloy
Electron shell 100 Fermium

historia

upptäckare eller uppfinnareArgonne, Los Alamos, U of Calif
fyndplatsUnited States
upptäcktsdatum1953
etymologiNamed in honor of the scientist Enrico Fermi.
uttalFER-mi-em (engelska)

Sources

Förekomst
Abundance in Earth's crust
Abundance in Oceans
Abundance in Human Body
0 %
Abundance in Meteor
0 %
Abundance in Sun
0 %
Abundance in Universe
0 %

Nuclear Screening Constants