Magnesium Element Information, Facts, Properties, Trends, Uses, Comparison with other elements
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.
It belongs to group 2 of the periodic table having trivial name alkaline earth metals*. You can also download Printable Periodic Table of Elements Flashcards for Magnesium in a PDF format.
Magnesium Facts
Read key information and facts about element Magnesium
Name | Magnesium |
Atomic Number | 12 |
Atomic Symbol | Mg |
Atomic Weight | 24.305 |
Phase | Solid |
Color | Silver |
Appearance | shiny grey solid |
Classification | Alkaline Earth Metal |
Natural Occurance | Primordial |
Group in Periodic Table | 2 |
Group Name | beryllium family |
Period in Periodic Table | period 3 |
Block in Periodic Table | s-block |
Electronic Configuration | [Ne] 3s2 |
Electronic Shell Structure (Electrons per shell) | 2, 8, 2 |
Melting Point | 923 K |
Boiling Point | 1363 K |
CAS Number | CAS7439-95-4 |
How to Locate Magnesium 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 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.
Magnesium History
The element Magnesium was discovered by J. Black in year 1755 in United Kingdom. Magnesium was first isolated by H. Davy in 1808. Magnesium derived its name from Magnesia, a district of Eastern Thessaly in Greece.
Discovered By | J. Black |
Discovery Date | 1755 in United Kingdom |
First Isolation | 1808 |
Isolated by | H. Davy |
Black observed that magnesia alba (MgO) was not quicklime(CaO). Davy isolated the metal electrochemically from magnesia.
Magnesium Uses
Magnesium is used in medicine like Epsom salts, milk of magnesia, chloride, and citrate. Magnesium is also important to both animal and plant life. Because it is less dense than aluminum, it is often mixed with aluminum for use in the plane and car constructions. It is also added to molten iron and steel to remove sulfur. Magnesium burns easily in the air and burns with a bright light, so it's used in flares, fireworks, and sparklers. Magnesium oxide is used to make heat-resistant bricks for fireplaces and furnaces. It is also added to cattle feed and fertilizers.
Magnesium Presence: Abundance in Nature and Around Us
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 %) | ppb by atoms (1ppb =10^-7 %) | |
---|---|---|
Abundance in Universe | 600000 | 30000 |
Abundance in Sun | 700000 | 30000 |
Abundance in Meteorites | 120000000 | 100000000 |
Abundance in Earth's Crust | 29000000 | 25000000 |
Abundance in Oceans | 1326000 | 337000 |
Abundance in Humans | 270000 | 70000 |
Crystal Structure of Magnesium
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.
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 |
---|---|---|
320.94 pm | 320.94 pm | 521.08 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.
Magnesium Atomic and Orbital Properties
Magnesium atoms have 12 electrons and the electronic shell structure is [2, 8, 2] with Atomic Term Symbol (Quantum Numbers) 1S0.
Atomic Number | 12 |
Number of Electrons (with no charge) | 12 |
Number of Protons | 12 |
Mass Number | 24 |
Number of Neutrons | 12 |
Shell structure (Electrons per energy level) | 2, 8, 2 |
Electron Configuration | [Ne] 3s2 |
Valence Electrons | 3s2 |
Valence (Valency) | 2 |
Main Oxidation States | 2 |
Oxidation States | 0, 1, 2 |
Atomic Term Symbol (Quantum Numbers) | 1S0 |
Bohr Atomic Model of Magnesium - Electrons per energy level
n | s | p | d | f |
---|
Ground State Electronic Configuration of Magnesium - neutral Magnesium atom
Abbreviated electronic configuration of Magnesium
The ground state abbreviated 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.
Unabbreviated electronic configuration of neutral Magnesium
Complete ground state electronic configuration for the Magnesium atom, Unabbreviated electronic configuration
1s2 2s2 2p6 3s2
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.
Atomic Structure of Magnesium
Magnesium atomic radius is 145 pm, while it's covalent radius is 130 pm.
Atomic Radius Calculated | 145 pm(1.45 Å) |
Atomic Radius Empirical | 150 pm (1.5 Å) |
Atomic Volume | 13.984 cm3/mol |
Covalent Radius | 130 pm (1.3 Å) |
Van der Waals Radius | 173 pm |
Neutron Cross Section | 0.063 |
Neutron Mass Absorption | 0.0001 |
Spectral Lines of Magnesium - Atomic Spectrum of Magnesium
A spectral line is a dark or bright line in an otherwise uniform and continuous spectrum, resulting from an excess or deficiency of photons in a narrow frequency range, compared with the nearby frequencies. Spectral lines are often used to identify atoms and molecules.
Spectral lines are the result of interaction between a quantum system and a single photon. A spectral line may be observed either as an emission line or an absorption line.
Spectral lines are highly atom-specific, and can be used to identify the chemical composition of any medium. Several elements, including helium, thallium, and caesium, were discovered by spectroscopic means. They are widely used to determine the physical conditions of stars and other celestial bodies that cannot be analyzed by other means.
Emission spectrum of Magnesium
Absorption spectrum of Magnesium
Magnesium Chemical Properties: Magnesium Ionization Energies and electron affinity
The electron affinity of Magnesium is 0 kJ/mol.
Valence | 2 |
Electronegativity | 1.31 |
ElectronAffinity | 0 kJ/mol |
Ionization Energy of Magnesium
Ionization energy is the amount of energy required to remove an electron from an atom or molecule.in chemistry, this energy is expresed in kilocalories per mole (kcal/mol) or kilojoules per mole (kJ/mol).
Refer to table below for Ionization energies of Magnesium
Ionization energy number | Enthalpy - kJ/mol |
---|---|
1st | 737.7 |
2nd | 1450.7 |
3rd | 7732.7 |
4th | 10542.5 |
5th | 13630 |
6th | 18020 |
7th | 21711 |
8th | 25661 |
9th | 31653 |
10th | 35458 |
11th | 169988 |
12th | 189368 |
Magnesium Physical Properties
Refer to below table for Magnesium Physical Properties
Density | 1.738 g/cm3(when liquid at m.p density is $1.584 g/cm3) |
Molar Volume | 13.984 cm3/mol |
Elastic Properties
Young Modulus | 45 |
Shear Modulus | 17 GPa |
Bulk Modulus | 45 GPa |
Poisson Ratio | 0.29 |
Hardness of Magnesium - Tests to Measure of Hardness of Element
Mohs Hardness | 2.5 MPa |
Vickers Hardness | - |
Brinell Hardness | 260 MPa |
Magnesium Electrical Properties
Electrical resistivity measures element's electrical resistance or how strongly it resists electric current.The SI unit of electrical resistivity is the ohm-metre (Ω⋅m). While Electrical conductivity is the reciprocal of electrical resistivity. It represents a element's ability to conduct electric current. The SI unit of electrical conductivity is siemens per metre (S/m).
Magnesium is a conductor of electricity. Refer to table below for the Electrical properties of Magnesium
Electrical conductors | Conductor |
Electrical Conductivity | 23000000 S/m |
Resistivity | 4.4e-8 m Ω |
Superconducting Point | - |
Magnesium Heat and Conduction Properties
Thermal Conductivity | 160 W/(m K) |
Thermal Expansion | 0.0000082 /K |
Magnesium Magnetic Properties
Magnetic Type | Paramagnetic |
Curie Point | - |
Mass Magnetic Susceptibility | 6.9e-9 m3/kg |
Molar Magnetic Susceptibility | 1.68e-10 m3/mol |
Volume Magnetic Susceptibility | 0.000012 |
Optical Properties of Magnesium
Refractive Index | - |
Acoustic Properties of Magnesium
Speed of Sound | 4602 m/s |
Magnesium Thermal Properties - Enthalpies and thermodynamics
Refer to table below for Thermal properties of Magnesium
Melting Point | 923 K(649.85 °C, 1201.730 °F) |
Boiling Point | 1363 K(1089.85 °C, 1993.730 °F) |
Critical Temperature | - |
Superconducting Point | - |
Enthalpies of Magnesium
Heat of Fusion | 8.7 kJ/mol |
Heat of Vaporization | 128 kJ/mol |
Heat of Combustion | -668 J/(kg K) |
Magnesium Isotopes - Nuclear Properties of Magnesium
Magnesium has 22 isotopes, with between 19 and 40 nucleons. Magnesium has 3 stable naturally occuring isotopes.
Isotopes of Magnesium - Naturally occurring stable Isotopes: 24Mg, 25Mg, 26Mg.
Isotope | Z | N | Isotope Mass | % Abundance | T half | Decay Mode |
---|---|---|---|---|---|---|
19Mg | 12 | 7 | 19 | Synthetic | ||
20Mg | 12 | 8 | 20 | Synthetic | ||
21Mg | 12 | 9 | 21 | Synthetic | ||
22Mg | 12 | 10 | 22 | Synthetic | ||
23Mg | 12 | 11 | 23 | Synthetic | ||
24Mg | 12 | 12 | 24 | 78.99% | Stable | |
25Mg | 12 | 13 | 25 | 10% | Stable | N/A |
26Mg | 12 | 14 | 26 | 11.01% | Stable | N/A |
27Mg | 12 | 15 | 27 | Synthetic | ||
28Mg | 12 | 16 | 28 | Synthetic | ||
29Mg | 12 | 17 | 29 | Synthetic | ||
30Mg | 12 | 18 | 30 | Synthetic | ||
31Mg | 12 | 19 | 31 | Synthetic | ||
32Mg | 12 | 20 | 32 | Synthetic | ||
33Mg | 12 | 21 | 33 | Synthetic | ||
34Mg | 12 | 22 | 34 | Synthetic | ||
35Mg | 12 | 23 | 35 | Synthetic | ||
36Mg | 12 | 24 | 36 | Synthetic | ||
37Mg | 12 | 25 | 37 | Synthetic | ||
38Mg | 12 | 26 | 38 | Synthetic | ||
39Mg | 12 | 27 | 39 | Synthetic | ||
40Mg | 12 | 28 | 40 | Synthetic |
Regulatory and Health - Health and Safety Parameters and Guidelines
The United States Department of Transportation (DOT) identifies hazard class of all dangerous elements/goods/commodities either by its class (or division) number or name. The DOT has divided these materials into nine different categories, known as Hazard Classes.
DOT Numbers | {1869,1418} |
DOT Hazard Class | 4.1 |
NFPA 704 is a Standard System for the Identification of the Hazards of Materials for Emergency Response. NFPA is a standard maintained by the US based National Fire Protection Association.
The health (blue), flammability (red), and reactivity (yellow) rating all use a numbering scale ranging from 0 to 4. A value of zero means that the element poses no hazard; a rating of four indicates extreme danger.
NFPA Fire Rating | 1 | Flash Points Above 93.3°C (200°F) |
NFPA Health Rating | 0 | Will not burn |
NFPA Reactivity Rating | 1 | Flash Points Above 93.3°C (200°F) |
NFPA Hazards |
Autoignition Point | 472 °C |
Flashpoint | 500 °C |
Database Search
List of unique identifiers to search the element in various chemical registry databases
Database | Identifier number |
---|---|
CAS Number - Chemical Abstracts Service (CAS) | CAS7439-95-4 |
RTECS Number | - |
CID Number | CID5462224 |
Gmelin Number | - |
NSC Number | - |
Compare Magnesium with other elements
Compare Magnesium with Group 2, Period 3 and Alkaline Earth Metal elements of the periodic table.
Compare Magnesium with all Group 2 elements
Compare Magnesium with all Period 3 elements
Compare Magnesium with all Alkaline Earth Metal elements
Frequently Asked Questions (FAQ)
Find the answers to the most frequently asked questions about Magnesium