La Lanthanum
Element Information, Facts, Properties, Trends, Uses, Comparison with other elements
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
| Name | Lanthanum |
| Atomic Number | 57 |
| Atomic Symbol | La |
| Atomic Weight | 138.9055 |
| Phase | Solid |
| Color | Silver |
| Appearance | silvery white |
| Classification | Lanthanide |
| Group in Periodic Table | - |
| Group Name | |
| Period in Periodic Table | period 6 |
| Block in Periodic Table | f -block |
| Electronic Configuration | [Xe] 5d1 6s2 |
| Electronic Shell Structure (Electrons per shell) | 2, 8, 18, 18, 9, 2 |
| Melting Point | 1193 K |
| Boiling Point | 3737 K |
| CAS Number | CAS7439-91-0 |
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 Universe | 2 | 0.02 |
| Abundance in Sun | 2 | 0.01 |
| Abundance in Meteorites | 290 | 40 |
| Abundance in Earth's Crust | 34000 | 5000 |
| Abundance in Oceans | 0.0034 | 0.00015 |
| 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)
| a | b | c |
|---|---|---|
| 377.2 pm | 377.2 pm | 1214.4 pm |
and the angles between them Lattice Angles (alpha, beta and gamma).
| alpha | beta | gamma |
|---|---|---|
| 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 Name | P63/mmc |
| Space Group Number | 194 |
| Crystal Structure | Simple Hexagonal |
| Number of atoms per unit cell |
The number of atoms per unit cell in a simple cubic, face-centered cubic and body-centred cubic are 1,4,2 respectively.
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 Number | 57 |
| Number of Electrons (with no charge) | 57 |
| Number of Protons | 57 |
| Mass Number | 139 |
| Number of Neutrons | 82 |
| Shell structure (Electrons per energy level) | 2, 8, 18, 18, 9, 2 |
| Electron Configuration | [Xe] 5d1 6s2 |
| Valence Electrons | 5d1 6s2 |
| Valence (Valency) | 3 |
| Main Oxidation States | 3 |
| Oxidation States | 0, 1, 2, 3 |
| Atomic Term Symbol (Quantum Numbers) | 2D3/2 |
Bohr Atomic Model of Lanthanum - Electrons per energy level
| n | s | p | d | f |
|---|
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.
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 Volume | 22.386 cm3/mol |
| Covalent Radius | 169 pm (1.69 Å) |
| Van der Waals Radius | - |
| Neutron Cross Section | 8.98 |
| Neutron Mass Absorption | 0.0023 |
Atomic Spectrum of Lanthanum
Lanthanum Chemical Properties: Lanthanum Ionization Energies and electron affinity
The electron affinity of Lanthanum is 48 kJ/mol.
| Valence | 3 |
| Electronegativity | 1.1 |
| ElectronAffinity | 48 kJ/mol |
Ionization Energy of Lanthanum
Refer to table below for Ionization energies of Lanthanum
| Ionization energy number | Enthalpy - kJ/mol |
|---|---|
| 1st | 538.1 |
| 2nd | 1067 |
| 3rd | 1850.3 |
| 4th | 4819 |
| 5th | 5940 |
Lanthanum Physical Properties
Refer to below table for Lanthanum Physical Properties
| Density | 6.146 g/cm3(when liquid at m.p density is $5.94 g/cm3) |
| Molar Volume | 22.386 cm3/mol |
Elastic Properties
| Young Modulus | 37 |
| Shear Modulus | 14 GPa |
| Bulk Modulus | 28 GPa |
| Poisson Ratio | 0.28 |
Hardness of Lanthanum - Tests to Measure of Hardness of Element
| Mohs Hardness | 2.5 MPa |
| Vickers Hardness | 491 MPa |
| Brinell Hardness | 363 MPa |
Lanthanum Electrical Properties
Lanthanum is Conductor of electricity. Refer to table below for the Electrical properties ofLanthanum
| Electrical Conductivity | 1600000 S/m |
| Resistivity | 6.1e-7 m Ω |
| Superconducting Point | 4.88 |
Lanthanum Heat and Conduction Properties
| Thermal Conductivity | 13 W/(m K) |
| Thermal Expansion | 0.0000121 /K |
Lanthanum Magnetic Properties
| Magnetic Type | Paramagnetic |
| Curie Point | - |
| Mass Magnetic Susceptibility | 1.1e-8 m3/kg |
| Molar Magnetic Susceptibility | 1.528e-9 m3/mol |
| Volume Magnetic Susceptibility | 0.00006761 |
Optical Properties of Lanthanum
| Refractive Index | - |
Acoustic Properties of Lanthanum
| Speed of Sound | 2475 m/s |
Lanthanum Thermal Properties - Enthalpies and thermodynamics
Refer to table below for Thermal properties of Lanthanum
| Melting Point | 1193 K (919.85°C, 1687.73 °F) |
| Boiling Point | 3737 K (3463.85°C, 6266.929999999999 °F) |
| Critical Temperature | - |
| Superconducting Point | 4.88 |
Enthalpies of Lanthanum
| Heat of Fusion | 6.2 kJ/mol |
| Heat of Vaporization | 400 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.
| Isotope | Z | N | Isotope Mass | % Abundance | T half | Decay Mode |
|---|---|---|---|---|---|---|
| 117La | 57 | 60 | 117 | Synthetic | ||
| 118La | 57 | 61 | 118 | Synthetic | ||
| 119La | 57 | 62 | 119 | Synthetic | ||
| 120La | 57 | 63 | 120 | Synthetic | ||
| 121La | 57 | 64 | 121 | Synthetic | ||
| 122La | 57 | 65 | 122 | Synthetic | ||
| 123La | 57 | 66 | 123 | Synthetic | ||
| 124La | 57 | 67 | 124 | Synthetic | ||
| 125La | 57 | 68 | 125 | Synthetic | ||
| 126La | 57 | 69 | 126 | Synthetic | ||
| 127La | 57 | 70 | 127 | Synthetic | ||
| 128La | 57 | 71 | 128 | Synthetic | ||
| 129La | 57 | 72 | 129 | Synthetic | ||
| 130La | 57 | 73 | 130 | Synthetic | ||
| 131La | 57 | 74 | 131 | Synthetic | ||
| 132La | 57 | 75 | 132 | Synthetic | ||
| 133La | 57 | 76 | 133 | Synthetic | ||
| 134La | 57 | 77 | 134 | Synthetic | ||
| 135La | 57 | 78 | 135 | Synthetic | ||
| 136La | 57 | 79 | 136 | Synthetic | ||
| 137La | 57 | 80 | 137 | Synthetic | ||
| 138La | 57 | 81 | 138 | 0.09% | Stable | N/A |
| 139La | 57 | 82 | 139 | 99.91% | Stable | |
| 140La | 57 | 83 | 140 | Synthetic | ||
| 141La | 57 | 84 | 141 | Synthetic | ||
| 142La | 57 | 85 | 142 | Synthetic | ||
| 143La | 57 | 86 | 143 | Synthetic | ||
| 144La | 57 | 87 | 144 | Synthetic | ||
| 145La | 57 | 88 | 145 | Synthetic | ||
| 146La | 57 | 89 | 146 | Synthetic | ||
| 147La | 57 | 90 | 147 | Synthetic | ||
| 148La | 57 | 91 | 148 | Synthetic | ||
| 149La | 57 | 92 | 149 | Synthetic | ||
| 150La | 57 | 93 | 150 | Synthetic | ||
| 151La | 57 | 94 | 151 | Synthetic | ||
| 152La | 57 | 95 | 152 | Synthetic | ||
| 153La | 57 | 96 | 153 | Synthetic | ||
| 154La | 57 | 97 | 154 | Synthetic | ||
| 155La | 57 | 98 | 155 | Synthetic |
Regulatory and Health - Health and Safety Parameters and Guidelines
Database Search
List of unique identifiers to search the element in various chemical registry databases
| Database | Identifier 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
FAQs
What is the electronic configuration of Lanthanum?
The electronic configuration of Lanthanum is 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 5d1 6s2.
What is the abbreviated electronic configuration of Lanthanum?
The abbreviated electronic configuration of Lanthanum is [Xe] 5d1 6s2. To form abbreviated notation of electronic configuration, the completely filled subshells are replaced by the noble gas of the preceding period in square brackets.
What is the symbol of Lanthanum?
Symbol of Lanthanum is La. Lanthanum is a chemical element with symbol La and atomic number 57.
What is the position of Lanthanum in the Periodic Table?
Lanthanum is a chemical element with the symbol La and atomic number 57. Lanthanum is the 57 element on the periodic table. It is located in group null and period 6 in the modern periodic table.
What is the atomic number of Lanthanum?
The atomic number of Lanthanum is 57.
What is the color of Lanthanum?
Lanthanum is of Silver color.
Who discovered Lanthanum?
The element Lanthanum was discovered by G. Mosander in year 1838 in Sweden. Lanthanum was first isolated by G. Mosander in 1841.
How many valence electrons does a Lanthanum atom have?
Lanthanum has 3 valence electrons. Lanthanum has 57 electrons out of which 3 valence electrons are present in the 5d1 6s2 outer orbitals of atom.
What is the melting Point of Lanthanum?
Melting Point of Lanthanum is 1193 K.
What is the boiling Point of Lanthanum?
Boiling Point of Lanthanum is 3737 K.
What is the melting Point of Lanthanum in Kelvin?
Melting Point of Lanthanum in Kelvin is 1193 K.
What is the boiling Point of Lanthanum in Kelvin?
Boiling Point of Lanthanum in Kelvin is 3737 K.
What is the electronic configuration of Lanthanum 57?
The electronic configuration of Lanthanum will be 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 5d1 6s2.
How do you write the electron configuration for Lanthanum?
The electronic configuration of Lanthanum will be 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 5d1 6s2.