Difference Between Magnesium and Magnesium Oxide

Main Difference – Magnesium vs Magnesium Oxide

Magnesium is an alkaline earth metal that is in the group 2 of the periodic table of elements. It can form many basic compounds. Magnesium often forms ionic compounds by forming the magnesium divalent cation. Magnesium oxide is one such ionic compound. It is a white solid. The main difference between magnesium and magnesium oxide is that magnesium is a chemical element whereas magnesium oxide is an ionic compound.  

Key Areas Covered

1. What is Magnesium
     – Definition, Chemical Properties
2. What is Magnesium Oxide
    – Definition, Chemical Properties
3. What is the Difference Between Magnesium and Magnesium Oxide
     – Comparison of Key Differences

Key Terms: Calcination, Hygroscopic, Magnesium, Magnesium Hydroxide, Magnesium Oxide

What is Magnesium

Magnesium is a chemical element having the symbol Mg. It is placed in the group 2, period 3 of the periodic table of the elements. The atomic number of magnesium is 12. This means magnesium has 12 protons in the nucleus. At room temperature and pressure conditions, Magnesium is in a solid phase. The electron configuration of magnesium is [Ne]3s². Therefore, it can have 0 and +2 oxidation states.

Figure 1: Chemical Structure of Magnesium

The melting point of Magnesium is about 650^oC. The atomic mass of Magnesium is given as 24 amu. It is in the s block of the periodic table. Magnesium and other elements in the same group are considered as alkaline earth metals. This is because the oxides they form have basic characteristics. The electronegativity of Magnesium is about 1.31. The atomic radius of Magnesium is about 160 pm.

Magnesium can be mainly found in mineral deposits. Such minerals include dolomite and magnesite. Seawater also has a considerable amount of magnesium ions dissolved in it. Magnesium has wide applications as a metal, especially in aircraft designing, and automotive designing.

What is Magnesium Oxide

Magnesium Oxide is an inorganic compound that has the chemical formula MgO. The molar mass of this compound is 40.304 g/mol. It is a white powder that is hygroscopic. This means it can absorb water from the air when exposed to the atmosphere.

Magnesium oxide is odorless and has a boiling point of 3600^oC. The melting point of this compound is about 2800^oC. A saturated solution of magnesium oxide has a pH value of 10.3. Therefore, it is a basic compound.

Figure 2: A Sample of Magnesium Oxide

Magnesium oxide is an ionic compound composed of magnesium ions and oxide ions in a lattice. There are ionic bonds in between cations and anions. When this compound is added to water, it forms magnesium hydroxide. But when magnesium hydroxide is heated, it gives magnesium oxide again. Magnesium oxide can be produced by calcination of magnesium carbonate or magnesium hydroxide.

Difference Between Magnesium and Magnesium Oxide

Definition

Magnesium: Magnesium is a chemical element having the symbol Mg.

Magnesium Oxide: Magnesium Oxide is an inorganic compound that has the chemical formula MgO.

Molar Mass

Magnesium: Molar mass of magnesium is 24 g/mol.

Magnesium Oxide: Molar mass of magnesium oxide is 40.304 g/mol.

Nature

Magnesium: Magnesium is a chemical element.

Magnesium Oxide: Magnesium oxide is an ionic compound.

Melting Point

Magnesium: The melting point of Magnesium is about 650°C.

Magnesium Oxide: The melting point of Magnesium oxide is about 2800°C.

Appearance

Magnesium: Magnesium has a shiny, silvery gray appearance.

Magnesium Oxide: Magnesium oxide is a white powder.

Conclusion

Magnesium is a chemical element where magnesium oxide is an ionic compound. This is the main difference between magnesium and magnesium oxide. Magnesium is a very useful metallic element due to its strength when compared to the light weight.

References:

1. “Magnesium oxide.” Wikipedia, Wikimedia Foundation, 30 Nov. 2017, Available here.
2. “MAGNESIUM OXIDE.” National Center for Biotechnology Information. PubChem Compound Database, U.S. National Library of Medicine, Available here.

Image Courtesy:

1. “Electron shell 012 magnesium” By Greg Robson – Application: Inkscape (CC BY-SA 2.0 uk) via Commons Wikimedia
2. “Magnesium oxide sample” By Adam Rędzikowski – Own work (CC BY-SA 4.0) via Commons Wikimedia