What is Potassium permanganate?
KMnO4 is an inorganic chemical compound. It is also known as Condy’s crystals or permanganate of potash. A German-Dutch chemist Johann Rudolf Glauber was the first to discover the production of KMnO4 in the year 1659. This compound is water-soluble and consists of two ions: Permanganate ion and potassium ion. It is a dark purple odourless solid in its physical state. When potassium permanganate crystals are dissolved in water the solution formed is purple in colour. It is considered as a strong oxidizing agent and does not produce toxic byproducts. It is usually prepared from other minerals such as manganese oxide
Physical Properties of Potassium Permanganate – KMnO4
- It is an odourless, purple to magenta crystalline solid.
- It is soluble in water, acetone, acetic acid, methanol, and pyridine
- It gets dissolved in ethanol and organic solvents
Chemical Properties Of Potassium Permanganate
- Very strong oxidizing agent and used for this reason in many reactions
- It can be seen while performing the redox reaction, in which the dark purple solution turns colourless and then into a brown solution.
- The above reaction can be performed in an acid or a base
|Molecular Weight/ Molar Mass of Potassium permanganate||158.034 g/mol|
|Density of Potassium permanganate||2.703 g/cm³|
|Storage temperature of Potassium permanganate||Room temperature|
|Melting Point of Potassium permanganate||240 °C|
Potassium Permanganate structure – KMnO4
Reactions of Potassium Permanganate (KMnO4)
1. Thermal decomposition:
When solid potassium permanganate is heated it undergoes decomposition. The reaction is as follows:
- 2KMnO4 → K2MnO4 + MnO2(s) + O2
2. Reaction with acid:
When permanganate reacts with concentrated hydrochloric acid it produces chlorine. In neutral solution, permanganate is reduced by three electrons to produce manganese dioxide, where the oxidation state of manganese is +4. Potassium permanganate reduces spontaneously in an alkaline solution and turns into green K2MnO4.
Uses Of Potassium Permanganate (KMnO4)
There are wide applications of KMnO4. Some important uses of potassium permanganate have been discussed below:
- It is used in qualitative analysis to determine the permanganate value
- It is used in as a regeneration chemical in well water treatment to remove hydrogen sulfide and iron
- It is used as a disinfectant to cure skin conditions like foot fungal infections, dermatitis
- It is used in the treatment of bacterial infections
- It is used in tanning leathers, printing fabrics
- It is used as bleach, pesticide, antiseptic
- It is used in industries as an oxidizing agent
Effects on Health
In a concentrated form, it is an irritant to human eyes and skin. It can react with many reducing agents or organic material but it is inflammable.
Learn more about the chemical behaviour and importance of KMnO4 with the expert faculties at BYJU’S.
Frequently asked questions
1. List two uses of potassium permanganate.
Ans: Two uses of potassium permanganate are-
- It is used to treat various skin diseases such as fungal infection in the foot
- It is used as an oxidizing agent in industries.
2. Potassium permanganate is ________ in colour.
3. Permanganate a good oxidizing agent. Why?
Ans: As the oxidation states of atoms increases the elements become more electronegative. Therefore, permanganate a good oxidizing agent.
4. Write the formula for potassium permanganate.
Ans: The chemical formula of potassium permanganate is KMnO4.