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Fm Fermium
Element Information, Facts, Properties, Trends, Uses, Comparison with other elements

100
Fm
Fermium
Element 100 of Periodic table is Fermium with atomic number 100, atomic weight 257. Fermium, symbol Fm, has a Body Centered Cubic structure and color. Fermium is a Actinide element. It is part of group null (). Know everything about Fermium Facts, Physical Properties, Chemical Properties, Electronic configuration, Atomic and Crystal Structure.
100 Fm - Fermium | SchoolMyKids

Fermium is a synthetic element with symbol Fm and atomic number 100. It is a member of the Actinide series. It is the heaviest element that can be formed by neutron bombardment of lighter elements, and hence the last element that can be prepared in macroscopic quantities, although pure fermium metal has not yet been prepared.

It belongs to group of the periodic table having trivial name .

Fermium Facts

Read key information and facts about element Fermium

NameFermium
Atomic Number100
Atomic SymbolFm
Atomic Weight257
PhaseSolid
Color-
Appearance-
ClassificationActinide
Group in Periodic Table-
Group Name
Period in Periodic Tableperiod 7
Block in Periodic Tablef -block
Electronic Configuration[Rn] 5f12 7s2
Electronic Shell Structure (Electrons per shell)2, 8, 18, 32, 30, 8, 2
Melting Point1800 K
Boiling Point-
CAS NumberCAS7440-72-4
Neighborhood Elements
123456789101112131415161718
1
1
H
Hydrogen
1.008

Atomic #

Electronic Shell #

Symbol
Name
Atomic Weight
HGas
HgLiquid
CSolid
Metals
Metalloids
NonMetals
Alkali metals
Alkali earth metals
Lanthanoids
Transition metals
Post-transition metals
Other nonmetals
Halogens
Nobel gas
Actinoids
2
He
Helium
4.003
2
3
Li
Lithium
6.941
4
Be
Beryllium
9.012
5
B
Boron
10.811
6
C
Carbon
12.011
7
N
Nitrogen
14.007
8
O
Oxygen
15.999
9
F
Fluorine
18.998
10
Ne
Neon
20.180
3
11
Na
Sodium
22.990
12
Mg
Magnesium
24.305
13
Al
Aluminium
26.982
14
Si
Silicon
28.085
15
P
Phosphorus
30.974
16
S
Sulfur
32.065
17
Cl
Chlorine
35.453
18
Ar
Argon
39.948
4
19
K
Potassium
39.098
20
Ca
Calcium
40.078
21
Sc
Scandium
44.956
22
Ti
Titanium
47.867
23
V
Vanadium
50.941
24
Cr
Chromium
51.996
25
Mn
Manganese
54.938
26
Fe
Iron
55.845
27
Co
Cobalt
58.933
28
Ni
Nickel
58.693
29
Cu
Copper
63.546
30
Zn
Zinc
65.409
31
Ga
Gallium
69.723
32
Ge
Germanium
72.640
33
As
Arsenic
74.922
34
Se
Selenium
78.960
35
Br
Bromine
79.904
36
Kr
Krypton
83.798
5
37
Rb
Rubidium
85.468
38
Sr
Strontium
87.620
39
Y
Yttrium
88.906
40
Zr
Zirconium
91.224
41
Nb
Niobium
92.906
42
Mo
Molybdenum
95.940
43
Tc
Technetium
98
44
Ru
Ruthenium
101.070
45
Rh
Rhodium
102.906
46
Pd
Palladium
106.420
47
Ag
Silver
107.868
48
Cd
Cadmium
112.411
49
In
Indium
114.818
50
Sn
Tin
118.710
51
Sb
Antimony
121.760
52
Te
Tellurium
127.600
53
I
Iodine
126.904
54
Xe
Xenon
131.293
6
55
Cs
Cesium
132.905
56
Ba
Barium
137.327
57 - 71
La - Lu
Lanthanides
72
Hf
Hafnium
178.490
73
Ta
Tantalum
180.948
74
W
Tungsten
183.840
75
Re
Rhenium
186.207
76
Os
Osmium
190.230
77
Ir
Iridium
192.217
78
Pt
Platinum
195.078
79
Au
Gold
196.967
80
Hg
Mercury
200.590
81
Tl
Thallium
204.383
82
Pb
Lead
207.200
83
Bi
Bismuth
208.980
84
Po
Polonium
209
85
At
Astatine
210
86
Rn
Radon
222
7
87
Fr
Francium
223
88
Ra
Radium
226
89 - 103
Ac - Lr
Actinides
104
Rf
Rutherfordium
261
105
Db
Dubnium
262
106
Sg
Seaborgium
266
107
Bh
Bohrium
264
108
Hs
Hassium
277
109
Mt
Meitnerium
268
110
Ds
Darmstadtium
281
111
Rg
Roentgenium
272
112
Cn
Copernicium
285
113
Nh
Nihonium
284
114
Fl
Flerovium
289
115
Mc
Moscovium
288
116
Lv
Livermorium
292
117
Ts
Tennessine
294
118
Og
Oganesson
294
Lanthanides
57
La
Lanthanum
138.905
58
Ce
Cerium
140.116
59
Pr
Praseodymium
140.908
60
Nd
Neodymium
144.240
61
Pm
Promethium
145
62
Sm
Samarium
150.360
63
Eu
Europium
151.964
64
Gd
Gadolinium
157.250
65
Tb
Terbium
158.925
66
Dy
Dysprosium
162.500
67
Ho
Holmium
164.930
68
Er
Erbium
167.259
69
Tm
Thulium
168.934
70
Yb
Ytterbium
173.040
71
Lu
Lutetium
174.967
Actinides
89
Ac
Actinium
227
90
Th
Thorium
232.038
91
Pa
Protactinium
231.036
92
U
Uranium
238.029
93
Np
Neptunium
237
94
Pu
Plutonium
244
95
Am
Americium
243
96
Cm
Curium
247
97
Bk
Berkelium
247
98
Cf
Californium
251
99
Es
Einsteinium
252
100
Fm
Fermium
257
101
Md
Mendelevium
258
102
No
Nobelium
259
103
Lr
Lawrencium
262

How to Locate Fermium on Periodic Table

Periodic table is arranged by atomic number, number of protons in the nucleus which is same as number of electrons. The atomic number increases from left to right. Periodic table starts at top left ( Atomic number 1) and ends at bottom right (atomic number 118). Therefore you can directly look for atomic number 100 to find Fermium on periodic table.

Another way to read periodic table and locate an element is by using group number (column) and period number (row). To locate Fermium on periodic table look for cross section of group - and period 7 in the modern periodic table.

Fermium History

The element Fermium was discovered by A. Ghiorso et al.(Argonne Laboratory, Los Alamos Laboratory and University of California, Berkeley) in year 1952 in United States. Fermium was first isolated by in . Fermium derived its name from Enrico Fermi, physicist.

Formed in the first thermonuclear explosion in November 1952, by irradiation of uranium with neutrons; kept secret for several years.

Fermium Presence: Abundance in Nature and Around Us

The table below shows the abundance of Fermium in Universe, Sun, Meteorites, Earth's Crust, Oceans and Human Body.

 ppb by weight (1ppb =10^-7 %)ppb by atoms (1ppb =10^-7 %)
Abundance in Universe--
Abundance in Sun--
Abundance in Meteorites--
Abundance in Earth's Crust--
Abundance in Oceans--
Abundance in Humans--

Crystal Structure of Fermium

The solid state structure of Fermium is Body Centered Cubic.

The Crystal structure can be described in terms of its unit Cell. The unit Cells repeats itself in three dimensional space to form the structure.

Unit Cell Parameters

The unit cell is represented in terms of its lattice parameters, which are the lengths of the cell edges Lattice Constants (a, b and c)

abc

and the angles between them Lattice Angles (alpha, beta and gamma).

alphabetagamma

The positions of the atoms inside the unit cell are described by the set of atomic positions ( xi, yi, zi) measured from a reference lattice point.

The symmetry properties of the crystal are described by the concept of space groups. All possible symmetric arrangements of particles in three-dimensional space are described by the 230 space groups (219 distinct types, or 230 if chiral copies are considered distinct.

Space Group Name- 100 Fm Fermium - Crystal Structure | SchoolMyKids
Oxidation StatesSpace Group Number-
Crystal StructureBody Centered Cubic

Fermium Atomic and Orbital Properties

Fermium atoms have 100 electrons and the electronic shell structure is [2, 8, 18, 32, 30, 8, 2] with Atomic Term Symbol (Quantum Numbers) 3H6.

Atomic Number100
Number of Electrons (with no charge)100
Number of Protons100
Mass Number257
Number of Neutrons157
Shell structure (Electrons per energy level)2, 8, 18, 32, 30, 8, 2
Electron Configuration[Rn] 5f12 7s2
Valence Electrons5f12 7s2
Valence (Valency)3
Main Oxidation States3
Oxidation States2, 3
Atomic Term Symbol (Quantum Numbers)3H6

Bohr Atomic Model of Fermium - Electrons per energy level

100 Fm Fermium - Electron Shell Structure | SchoolMyKids
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Ground State Electronic Configuration of Fermium - neutral Fermium atom

Abbreviated electronic configuration of Fermium

The ground state abbreviated electronic configuration of Neutral Fermium atom is [Rn] 5f12 7s2. The portion of Fermium configuration that is equivalent to the noble gas of the preceding period, is abbreviated as [Rn]. For atoms with many electrons, this notation can become lengthy and so an abbreviated notation is used. This is important as it is the Valence electrons 5f12 7s2, electrons in the outermost shell that determine the chemical properties of the element.

Unabbreviated electronic configuration of neutral Fermium

Complete ground state electronic configuration for the Fermium atom, Unabbreviated electronic configuration

1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f12 7s2

Electrons are filled in atomic orbitals as per the order determined by the Aufbau principle, Pauli Exclusion Principle and Hund’s Rule.

  • As per the Aufbau principle the electrons will occupy the orbitals having lower energies before occupying higher energy orbitals. According to this principle, electrons are filled in the following order: 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f, 5d, 6p, 7s, 5f, 6d, 7p…
  • The Pauli exclusion principle states that a maximum of two electrons, each having opposite spins, can fit in an orbital.
  • Hund's rule states that every orbital in a given subshell is singly occupied by electrons before a second electron is filled in an orbital.
  • Electron configuration of Fermium
    Atomic Structure of Fermium

    Fermium atomic radius is - , while it's covalent radius is - .

    Atomic Radius Calculated

    - (0 Å)

    Atomic Radius Empirical

    - (0 Å)

    Atomic Volume-
    Covalent Radius-
    Van der Waals Radius-
    Neutron Cross Section5800
    Neutron Mass Absorption -

    Atomic Spectrum of Fermium

    Atomic Spectrum of Fermium | SchoolMyKids

    Fermium Chemical Properties: Fermium Ionization Energies and electron affinity

    The electron affinity of Fermium is - .

    Valence3
    Electronegativity1.3
    ElectronAffinity-

    Ionization Energy of Fermium

    Refer to table below for Ionization energies of Fermium

    Ionization energy numberEnthalpy - kJ/mol
    1st627

    Fermium Physical Properties

    Refer to below table for Fermium Physical Properties

    Density-
    Molar Volume-

    Elastic Properties

    Young Modulus-
    Shear Modulus-
    Bulk Modulus -
    Poisson Ratio-

    Hardness of Fermium - Tests to Measure of Hardness of Element

    Mohs Hardness-
    Vickers Hardness-
    Brinell Hardness-

    Fermium Electrical Properties

    Fermium is Conductor of electricity. Refer to table below for the Electrical properties ofFermium

    Electrical Conductivity-
    Resistivity-
    Superconducting Point-

    Fermium Heat and Conduction Properties

    Thermal Conductivity-
    Thermal Expansion-

    Fermium Magnetic Properties

    Magnetic Type-
    Curie Point-
    Mass Magnetic Susceptibility-
    Molar Magnetic Susceptibility-
    Volume Magnetic Susceptibility-

    Optical Properties of Fermium

    Refractive Index-

    Acoustic Properties of Fermium

    Speed of Sound-

    Fermium Thermal Properties - Enthalpies and thermodynamics

    Refer to table below for Thermal properties of Fermium

    Melting Point1800 K (1526.85°C, 2780.33 °F)
    Boiling Point- (-273.15°C, -459.66999999999996 °F)
    Critical Temperature-
    Superconducting Point-

    Enthalpies of Fermium

    Heat of Fusion-
    Heat of Vaporization-
    Heat of Combustion-

    Fermium Isotopes - Nuclear Properties of Fermium

    Fermium has 19 isotopes, with between 242 and 260 nucleons. Fermium has 0 stable naturally occuring isotopes.

    Isotopes of Fermium - Naturally occurring stable Isotopes: -.

    IsotopeZNIsotope Mass% AbundanceT halfDecay Mode
    242Fm100142242Synthetic
    243Fm100143243Synthetic
    244Fm100144244Synthetic
    245Fm100145245Synthetic
    246Fm100146246Synthetic
    247Fm100147247Synthetic
    248Fm100148248Synthetic
    249Fm100149249Synthetic
    250Fm100150250Synthetic
    251Fm100151251Synthetic
    252Fm100152252Synthetic
    253Fm100153253Synthetic
    254Fm100154254Synthetic
    255Fm100155255Synthetic
    256Fm100156256Synthetic
    257Fm100157257Synthetic100.5 dAlphaEmission
    258Fm100158258Synthetic
    259Fm100159259Synthetic
    260Fm100160260Synthetic

    Database Search

    List of unique identifiers to search the element in various chemical registry databases

    DatabaseIdentifier number
    CAS Number - Chemical Abstracts Service (CAS)CAS7440-72-4
    RTECS Number-
    CID Number -
    Gmelin Number-
    NSC Number-

    Compare Fermium with other elements

    Compare Fermium with all Group elements

    Compare Fermium with all Period 7 elements

    Compare Fermium with all Actinide elements