Magnesium is a chemical element with symbol Mg and atomic number 12. It is a shiny gray solid which bears a close physical resemblance to the other five elements in the second column (Group 2, or alkaline earth metals) of the periodic table:they each have the same electron configuration in their outer electron shell producing a similar crystal structure. Magnesium is the ninth most abundant element in the universe.
Read key information and facts about element Magnesium
|Classification||alkaline earth metal|
|Group in Periodic Table||2|
|Group Name||beryllium family|
|Period in Periodic Table||3|
|Block in Periodic Table||s-block|
|Electronic Configuration||[Ne] 3s2|
|Melting Point||650 °C|
|Boiling Point||1090 °C|
|Electronic Shell Structure||[2, 8, 2]|
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 12 to find Magnesium 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 Magnesium on periodic table look for cross section of group 2 and period 3 in the modern periodic table.
The element Magnesium was discovered by Joseph Black in year 1755 in United Kingdom . Magnesium derived its name from Magnesia, a district of Eastern Thessaly in Greece
The table below shows the abundance of Magnesium in Universe, Sun, Meteorites, Earth's Crust, Oceans and Human Body.
|Ppb by weight (1ppb =10^-7 %)|
|Abundance in Universe||0.0006|
|Abundance in Sun||0.0007|
|Abundance in Meteorites||0.12|
|Abundance in Earth's Crust||0.029|
|Abundance in Oceans||0.0013|
|Abundance in Humans||0.00027|
The solid state structure of Magnesium 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.
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)
and the angles between them Lattice Angles (alpha, beta and gamma).
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|
Magnesium atoms have 12 electrons and the electronic shell structure is [2, 8, 2] with Atomic Term Symbol (Quantum Numbers) 1S0.
|Number of Electrons (with no charge)||12|
|Number of Protons||12|
|Number of Neutrons||12|
|Shell structure (Electrons per energy level)||[2, 8, 2]|
|Electron Configuration||[Ne] 3s2|
|Atomic Term Symbol (Quantum Numbers)||1S0|
Shell Structure of Magnesium - Electrons per energy level
The ground state electronic configuration of Neutral Magnesium atom is [Ne] 3s2. The portion of Magnesium configuration that is equivalent to the noble gas of the preceding period, is abbreviated as [Ne]. 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 3s2, electrons in the outermost shell that determine the chemical properties of the element.
Complete ground state electronic configuration for the Magnesium atom, Unabbreviated electronic configuration
1s2 2s2 2p6 3s2
Magnesium atomic radius is 145 pm, while it's covalent radius is 130 pm.
145 pm (1.45 Å)
|Atomic Volume||13.9844649022 cm3|
|Covalent Radius||130 pm (1.3 Å)|
|Van der Waals Radius||173 pm|
|Neutron Cross Section||0.063 σa/barns|
The electron affinity of Magnesium is 0 kJ/mol
Refer to table below for Ionization energies of Magnesium
|Ionization energy number||Enthalpy - kJ/mol|
Refer to below table for Magnesium Physical Properties
|Molar Volume||13.9844649022 cm3|
|Young Modulus||45 GPa|
|Shear Modulus||17 GPa|
|Bulk Modulus||45 GPa|
|Mohs Hardness||2.5 MPa|
|Brinell Hardness||260 MPa|
Magnesium is Conductor of electricity. Refer to table below for the Electrical properties of Magnesium
|Electrical Conductivity||2.3×107 S/m|
|Resistivity||4.4×10-8 m Ω|
|Thermal Conductivity||160 W/(m K)|
|Thermal Expansion||8.2×10-6 K-1|
|Mass Magnetic Susceptibility||6.9×10-9|
|Molar Magnetic Susceptibility||1.68×10-10|
|Volume Magnetic Susceptibility||1.2e-05|
|Speed of Sound||4602 m/s|
Refer to table below for Thermal properties of Magnesium
|Melting Point||923 K (650 °C)|
|Boiling Point||1363 K (1090 °C)|
|Heat of Fusion||8.7 kJ/mol|
|Heat of Vaporization||128 kJ/mol|
|Heat of Combustion||-668 J/(kg K)|
Isotopes of rhodium. Naturally occurring Magnesium has 3 stable isotope - 24Mg, 25Mg, 26Mg.
|Isotope||Isotope Mass||% Abundance||T half||Decay Mode|
|DOT Hazard Class||4.1|
|NFPA Fire Rating||1|
|NFPA Health Rating||0|
|NFPA Reactivity Rating||1|
|Autoignition Point||472 °C|
List of unique identifiers to search the element in various chemical registry databases
|CAS Number - Chemical Abstracts Service (CAS)||CAS7439-95-4|
|Alkali Metals||Alkaline Earth Metals|
|Transition Metals||Post-Transition Metals|