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La Lanthanum
Element Information, Facts, Properties, Trends, Uses, Comparison with other elements

57
La
Lanthanum
Element 57 of Periodic table is Lanthanum with atomic number 57, atomic weight 138.9055. Lanthanum, symbol La, has a Simple Hexagonal structure and Silver color. Lanthanum is a Lanthanide element. It is part of group null (). Know everything about Lanthanum Facts, Physical Properties, Chemical Properties, Electronic configuration, Atomic and Crystal Structure.
57 La - Lanthanum | SchoolMyKids

Lanthanum is a soft, ductile, silvery-white metallic chemical element with symbol La and atomic number 57. It tarnishes rapidly when exposed to air and is soft enough to be cut with a knife. It gave its name to the Lanthanide series, a group of 15 similar elements between lanthanum and lutetium in the periodic table:it is also sometimes considered the first element of the 6th-period transition metals.

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

Lanthanum Facts

Read key information and facts about element Lanthanum

NameLanthanum
Atomic Number57
Atomic SymbolLa
Atomic Weight138.9055
PhaseSolid
ColorSilver
Appearancesilvery white
ClassificationLanthanide
Group in Periodic Table-
Group Name
Period in Periodic Tableperiod 6
Block in Periodic Tablef -block
Electronic Configuration[Xe] 5d1 6s2
Electronic Shell Structure (Electrons per shell)2, 8, 18, 18, 9, 2
Melting Point1193 K
Boiling Point3737 K
CAS NumberCAS7439-91-0
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 Lanthanum 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 57 to find Lanthanum 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 Lanthanum on periodic table look for cross section of group - and period 6 in the modern periodic table.

Lanthanum History

The element Lanthanum was discovered by G. Mosander in year 1838 in Sweden. Lanthanum was first isolated by G. Mosander in 1841. Lanthanum derived its name from the Greek lanthanein, meaning 'to lie hidden'.

Mosander found a new element in samples of ceria and published his results in 1842, but later he showed that thislanthanacontained four more elements.

Lanthanum Presence: Abundance in Nature and Around Us

The table below shows the abundance of Lanthanum 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 Universe20.02
Abundance in Sun20.01
Abundance in Meteorites29040
Abundance in Earth's Crust340005000
Abundance in Oceans0.00340.00015
Abundance in Humans--

Crystal Structure of Lanthanum

The solid state structure of Lanthanum is Simple Hexagonal.

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
377.2 pm377.2 pm1214.4 pm

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

alphabetagamma
π/2 π/2 2 π/3

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 NameP63/mmc 57 La Lanthanum - Crystal Structure | SchoolMyKids
Oxidation StatesSpace Group Number194
Crystal StructureSimple Hexagonal

Lanthanum Atomic and Orbital Properties

Lanthanum atoms have 57 electrons and the electronic shell structure is [2, 8, 18, 18, 9, 2] with Atomic Term Symbol (Quantum Numbers) 2D3/2.

Atomic Number57
Number of Electrons (with no charge)57
Number of Protons57
Mass Number139
Number of Neutrons82
Shell structure (Electrons per energy level)2, 8, 18, 18, 9, 2
Electron Configuration[Xe] 5d1 6s2
Valence Electrons5d1 6s2
Valence (Valency)3
Main Oxidation States3
Oxidation States0, 1, 2, 3
Atomic Term Symbol (Quantum Numbers)2D3/2

Bohr Atomic Model of Lanthanum - Electrons per energy level

57 La Lanthanum - Electron Shell Structure | SchoolMyKids
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Ground State Electronic Configuration of Lanthanum - neutral Lanthanum atom

Abbreviated electronic configuration of Lanthanum

The ground state abbreviated electronic configuration of Neutral Lanthanum atom is [Xe] 5d1 6s2. The portion of Lanthanum configuration that is equivalent to the noble gas of the preceding period, is abbreviated as [Xe]. 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 5d1 6s2, electrons in the outermost shell that determine the chemical properties of the element.

Unabbreviated electronic configuration of neutral Lanthanum

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

1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 5d1 6s2

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 Lanthanum
    Atomic Structure of Lanthanum

    Lanthanum atomic radius is 195 pm, while it's covalent radius is 169 pm.

    Atomic Radius Calculated

    195 pm (1.95 Å)

    Atomic Radius Empirical

    195 pm (1.95 Å)

    Atomic Volume22.386 cm3/mol
    Covalent Radius169 pm (1.69 Å)
    Van der Waals Radius-
    Neutron Cross Section8.98
    Neutron Mass Absorption 0.0023

    Atomic Spectrum of Lanthanum

    Atomic Spectrum of Lanthanum | SchoolMyKids

    Lanthanum Chemical Properties: Lanthanum Ionization Energies and electron affinity

    The electron affinity of Lanthanum is 48 kJ/mol.

    Valence3
    Electronegativity1.1
    ElectronAffinity48 kJ/mol

    Ionization Energy of Lanthanum

    Refer to table below for Ionization energies of Lanthanum

    Ionization energy numberEnthalpy - kJ/mol
    1st538.1
    2nd1067
    3rd1850.3
    4th4819
    5th5940

    Lanthanum Physical Properties

    Refer to below table for Lanthanum Physical Properties

    Density6.146 g/cm3(when liquid at m.p density is $5.94 g/cm3)
    Molar Volume22.386 cm3/mol

    Elastic Properties

    Young Modulus37
    Shear Modulus14 GPa
    Bulk Modulus 28 GPa
    Poisson Ratio0.28

    Hardness of Lanthanum - Tests to Measure of Hardness of Element

    Mohs Hardness2.5 MPa
    Vickers Hardness491 MPa
    Brinell Hardness363 MPa

    Lanthanum Electrical Properties

    Lanthanum is Conductor of electricity. Refer to table below for the Electrical properties ofLanthanum

    Electrical Conductivity1600000 S/m
    Resistivity6.1e-7 m Ω
    Superconducting Point4.88

    Lanthanum Heat and Conduction Properties

    Thermal Conductivity13 W/(m K)
    Thermal Expansion0.0000121 /K

    Lanthanum Magnetic Properties

    Magnetic TypeParamagnetic
    Curie Point-
    Mass Magnetic Susceptibility1.1e-8 m3/kg
    Molar Magnetic Susceptibility1.528e-9 m3/mol
    Volume Magnetic Susceptibility0.00006761

    Optical Properties of Lanthanum

    Refractive Index-

    Acoustic Properties of Lanthanum

    Speed of Sound2475 m/s

    Lanthanum Thermal Properties - Enthalpies and thermodynamics

    Refer to table below for Thermal properties of Lanthanum

    Melting Point1193 K (919.85°C, 1687.73 °F)
    Boiling Point3737 K (3463.85°C, 6266.929999999999 °F)
    Critical Temperature-
    Superconducting Point4.88

    Enthalpies of Lanthanum

    Heat of Fusion6.2 kJ/mol
    Heat of Vaporization400 kJ/mol
    Heat of Combustion-

    Lanthanum Isotopes - Nuclear Properties of Lanthanum

    Lanthanum has 39 isotopes, with between 117 and 155 nucleons. Lanthanum has 1 stable naturally occuring isotopes.

    Isotopes of Lanthanum - Naturally occurring stable Isotopes: 139La.

    IsotopeZNIsotope Mass% AbundanceT halfDecay Mode
    117La5760117Synthetic
    118La5761118Synthetic
    119La5762119Synthetic
    120La5763120Synthetic
    121La5764121Synthetic
    122La5765122Synthetic
    123La5766123Synthetic
    124La5767124Synthetic
    125La5768125Synthetic
    126La5769126Synthetic
    127La5770127Synthetic
    128La5771128Synthetic
    129La5772129Synthetic
    130La5773130Synthetic
    131La5774131Synthetic
    132La5775132Synthetic
    133La5776133Synthetic
    134La5777134Synthetic
    135La5778135Synthetic
    136La5779136Synthetic
    137La5780137Synthetic
    138La57811380.09%StableN/A
    139La578213999.91%Stable
    140La5783140Synthetic
    141La5784141Synthetic
    142La5785142Synthetic
    143La5786143Synthetic
    144La5787144Synthetic
    145La5788145Synthetic
    146La5789146Synthetic
    147La5790147Synthetic
    148La5791148Synthetic
    149La5792149Synthetic
    150La5793150Synthetic
    151La5794151Synthetic
    152La5795152Synthetic
    153La5796153Synthetic
    154La5797154Synthetic
    155La5798155Synthetic

    Regulatory and Health - Health and Safety Parameters and Guidelines

    Database Search

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

    DatabaseIdentifier number
    CAS Number - Chemical Abstracts Service (CAS)CAS7439-91-0
    RTECS Number-
    CID Number CID23926
    Gmelin Number-
    NSC Number-

    Compare Lanthanum with other elements

    Compare Lanthanum with all Group elements

    Compare Lanthanum with all Period 6 elements

    Compare Lanthanum with all Lanthanide elements