Magnesium Carbonate(MgCO3) Properties(25 Facts)

Magnesium carbonate is one of the compounds of magnesium generally obtained by mining magnesite. Let us learn more about Magnesium carbonate’s properties.

Magnesium carbonate is an ionic compound that is primarily used for the production of magnesium oxide. It is also used in many other things, such as flooring, fireproofing, chalk, toothpaste, etc.

In this article, we will explore Magnesium carbonate’s nomenclature, important properties, and structure.

Magnesium carbonate IUPAC name

The IUAPC name of Magnesium carbonate is magnesium carbonate.

Magnesium carbonate chemical formula

The chemical formula of Magnesium carbonate is MgCO3.

Magnesium carbonate CAS number

The CAS number of MgCO3 is 546-93-0.

Magnesium carbonate ChemSpider ID

The ChemSpider ID of Magnesium carbonate is 10563.

Magnesium carbonate chemical classification

MgCO3 is chemically classified as an inorganic salt and as a carbonate.

Magnesium carbonate molar mass

Magnesium carbonate’s Molar Mass is 26.3207. The calculation is shown below:

mgco3mass 1
Calculation of Molar Mass of MgCO3

Magnesium carbonate color

The color of MgCO3 is white.

Magnesium carbonate viscosity

MgCO3‘s viscosity cannot be measured since it decomposes upon heating.

Magnesium carbonate molar density

The molar density of anhydrous MgCO3 is 0.0350836 mol/cm3.

Magnesium carbonate melting point

The melting point of anhydrous MgCO3 is 350 °C

Magnesium carbonate boiling point

The boiling point of MgCO3 is not known since it decomposes upon heating at high temperatures before boiling:

MgCO3  → MgO + CO2

Magnesium carbonate state at room temperature

MgCO3 is a solid at room temperature.

Magnesium carbonate ionic bond

Mg2+ and CO­32- ions are joined by ionic bonds, and the bonds between C and O atoms are covalent.

MgCO3 bonds

Magnesium carbonate ionic radius

The radius is not defined for Magnesium carbonate since the ionic/Covalent radii are defined and measured only for atoms and not molecules. Magnesium carbonate is an ionic compound containing five atoms.

Magnesium carbonate electron configurations

Electron configurations show us how the electrons are distributed in an atomic orbital around the nucleus. Let us see the electronic configuration of MgCO3.

  • The electron configuration of Mg2+ in Magnesium carbonate is 1s2 2s2 2p6, which can also be written in the noble gas configuration as [Ne]3s0.
  • It is not as simple to describe the electronic configuration of CO­32- by simply filling atomic orbitals since it will require complicated molecular orbitals and knowledge of symmetry and group theory.

Magnesium carbonate oxidation state

The Mg atom in Magnesium carbonate is in a +2 Oxidation state. The CO32- ion is in -2 oxidation state, where each O atom is in an oxidation state of -2, and the C atom is in a +4 oxidation state.

Magnesium carbonate alkaline

MgCO3 is alkaline and reacts with acids to form salt and carbonic acid.

MgCO­­3 + 2 HCl → MgCl­­­2 + H2CO3

Is Magnesium carbonate odourless

Magnesium carbonate is odourless.

Is Magnesium carbonate paramagnetic

Paramagnetic substances are attracted to magnets; due to an unpaired electron that aligns its magnetic moment with the magnetic field. Let us see if MgCO3 is paramagnetic.

Magnesium Carbonate is not paramagnetic since all the electrons of the MgCO3 are paired in both Mg2+ and CO­32- ions.

Magnesium carbonate hydrates

MgCO3 forms three different hydrates in addition to the anhydrous form:

TypeFormulaNo. of water moleculesMolar Mass
Hydrates of Magnesium Carbonate

Magnesium carbonate crystal structure

Anhydrous magnesium carbonate, also known as Magnesite, crystallizes in a calcite structure. The hydrated forms have a triclinic structure.

Magnesium carbonate polarity and conductivity

  • MgCO3 is polar since it is an ionic compound.
  • MgCO3 may provide ions to conduct electricity in the molten state.

Magnesium carbonate reaction with acid

Magnesium carbonate is basic and will react with most acids to form salt and carbonic acid.

MgCO­­3 + H2SO­4 → MgSO­4 + H2CO3

Magnesium carbonate reaction with base

MgCO3 does not react with bases.

Magnesium carbonate reaction with oxide

MgCO3 is basic, so it will react with acidic oxides such as H­3PO4.

3MgCO­­3 + 2H3PO­4 → Mg3(PO­4)2 + 3H2CO3


We learned about Magnesium carbonate’s physical and chemical properties, a highly versatile compound used in medicines, chalk, as an industrial precursor, and the limestone we use on our floors.