Difference Between Osmium Tetroxide and Potassium Permanganate

The key difference between osmium tetroxide and potassium permanganate is that osmium tetroxide is a covalent compound containing an oxide of osmium whereas potassium permanganate is an ionic compound containing potassium ions and manganite anions.

Osmium tetroxide and potassium permanganate are inorganic compounds. Both these compounds occur in the solid-state at room temperature, but they have very different chemical and physical properties because they have different atoms and different chemical bonds between atoms.

CONTENTS

1. Overview and Key Difference
2. What is Osmium Tetroxide 
3. What is Potassium Permanganate
4. Side by Side Comparison – Osmium Tetroxide vs Potassium Permanganate in Tabular Form
5. Summary

What is Osmium Tetroxide?

Osmium tetroxide is an oxide of osmium having the chemical formula OsO₄. It is in the solid-state at room temperature. Although osmium is rare and toxic, it has a wide variety of uses. The osmium tetroxide solid is a volatile solid. Therefore, it undergoes sublimation (convert into the gas phase without going through a liquid phase). It is usually colourless in its pure form but samples appear in slightly yellow colour. This is due to the presence of OsO₂ as an impurity.

In this osmium tetroxide compound, the osmium atom is in +8 oxidation state. The solid osmium tetroxide has a monoclinic crystal structure. But if we consider a single osmium tetroxide molecule, it is tetrahedral, and it is nonpolar. This solid has an acrid chlorine-like odour. It is slightly water-soluble but soluble in many organic solvents. We can produce osmium tetroxide via treating osmium power with oxygen gas at an ambient temperature, which slowly reacts to form the osmium tetroxide compound.

When considering the uses of osmium tetroxide, there is a wide variety of applications, including organic compound synthesis, biological staining, polymer staining, osmium ore refining, etc. However, we need to take preventive measures before handling this compound because it is a toxic compound.

What is Potassium Permanganate?

Potassium permanganate is an inorganic compound having the chemical formula KMnO₄. It is an ionic compound (a salt of potassium) containing a potassium cation in combination with a manganite anion. This compound is a strong oxidizing agent. This is because it can undergo reduction through the manganese atom in the anion; manganese in this compound is in +7 oxidation state, which is the highest oxidation state it can reside in. Therefore, it can be easily reduced into lower oxidation states by oxidizing other oxidizable compounds.

Potassium permanganate occurs in the solid-state at room temperature. It appears like needle-like structures that are dark purple in colour. It is highly water-soluble and when dissolved – it forms a dark purple coloured solution. We can produce potassium permanganate industrially through the fusion of manganese oxide with potassium hydroxide, followed by heating in air.

There are many uses of potassium permanganate in different areas such as medical uses, water treatment, synthesis of organic compounds, analytical uses such as titrations, fruit preservation, included in survival kits as a hypergolic fire starter, etc.

What is the Difference Between Osmium Tetroxide and Potassium Permanganate?

The key difference between osmium tetroxide and potassium permanganate is that osmium tetroxide is a covalent compound containing an oxide of osmium, whereas potassium permanganate is an ionic compound containing potassium ion and manganite anion. Moreover, osmium tetroxide is solid at room temperature with a slight yellow -colourless appearance, while potassium permanganate is a dark purple coloured solid with a needle-like structure.

Below is a more detailed comparison of the difference between osmium tetroxide and potassium permanganate.

Summary – Osmium Tetroxide vs Potassium Permanganate

Osmium tetroxide and potassium permanganate are inorganic compounds. The key difference between osmium tetroxide and potassium permanganate is that osmium tetroxide is a covalent compound containing an oxide of osmium whereas potassium permanganate is an ionic compound containing potassium ion and manganite anion.

Reference:

1. “Potassium Permanganate.” Wikipedia, Wikimedia Foundation, 7 Feb. 2020, Available here.

Image Courtesy:

1. “Osmium tetroxide 0.1 gram in ampoule” By W. Oelen – (CC BY-SA 3.0) via Commons Wikimedia
2. “Potassium-permanganate-sample” By Benjah-bmm27 – Own work (Public Domain) via Commons Wikimedia