The key difference between potassium permanganate and potassium dichromate is that potassium permanganate has a dark purple colour, whereas potassium dichromate has a red-orange colour.
Potassium permanganate and potassium dichromate are very common in laboratories because we commonly use them in titration procedures. Although these two compounds contain potassium as a constituent, we can easily distinguish them by just looking at them because they have a very different appearance.
CONTENTS
1. Overview and Key Difference
2. What is Potassium Permanganate
3. What is Potassium Dichromate
4. Side by Side Comparison –Potassium Permanganate vs Potassium Dichromate in Tabular Form
5. Summary
What is Potassium Permanganate?
Potassium permanganate is an inorganic compound which has the chemical formula KMnO4. Thus, the compound is a salt of potassium because it has the two ions, K+ and MnO4–. The metal manganese is in +7 oxidation state. The compound exists in the solid state at room temperature and appears as a dark purple solid compound. Besides, it is an important medication to clean wounds.
Figure 01: A Sample of Potassium Permanganate
Moreover, potassium permanganate is a strong oxidizing agent. It is water soluble, and upon dissolving in water, it gives pink or purple coloured solutions. The evaporation of water from this solution gives dark purple, glistening crystals.
Furthermore, this compound is a strong oxidant that does not produce any toxic byproduct. Thus, it is very useful in different applications. The fields of application include medicine, water treatment, synthesis of organic compounds, fruit preservation, etc.
What is Potassium Dichromate?
Potassium dichromate is an inorganic compound having the chemical formula K2Cr2O7. The compound has a bright, red-orange appearance. Also, it is an oxidizing agent. Therefore, there are many applications of this compound. However, as like many chromium compounds, potassium dichromate too is acutely harmful to our health.
Figure 02: A Sample of Potassium Dichromate
Coming to production, there are two ways to produce potassium dichromate. One is via the reaction between potassium chloride and sodium dichromate. The second method is by roasting the chromate ore with potassium hydroxide.
Moreover, potassium dichromate readily dissolves in water, and upon dissolution, it undergoes ionization. When considering the applications, it is used as a precursor for potassium chrome alum (a chemical used in leather industry). Other than that, it is also used for cleaning purposes, in constructions, in photography, etc.
What is the Difference Between Potassium Permanganate and Potassium Dichromate?
Potassium permanganate is an inorganic compound which has the chemical formula KMnO4 while potassium dichromate is an inorganic compound having the chemical formula K2Cr2O7. The key difference between potassium permanganate and potassium dichromate is that potassium permanganate has a dark purple colour, whereas potassium dichromate has a red-orange colour. When considering the oxidation states of the metal atoms in these compounds, manganese in potassium permanganate has +7 oxidation state where chromium in potassium dichromate has +6 oxidation state.
The below infographic shows more comparisons related to the difference between potassium permanganate and potassium dichromate.
Summary – Potassium Permanganate vs Potassium Dichromate
Potassium permanganate and potassium dichromate are potassium salts. The key difference between potassium permanganate and potassium dichromate is that potassium permanganate has a dark violet colour, whereas potassium dichromate has a red-orange colour.
Reference:
1.“Potassium Permanganate.” Potassium Permanganate – an Overview | ScienceDirect Topics, Available here.
Image Courtesy:
1. “Potassium-dichromate-sample” By Benjah-bmm27 – Own work (Public Domain) via Commons Wikimedia
2. “Potassium-permanganate-sample” By Benjah-bmm27 – Own work (Public Domain) via Commons Wikimedia