A dark purple crystalline compound, used as an oxidizing agent and disinfectant and in deodorizers and dyes.
M. S. D. S.
Potassium Permanganate (KMnO4) is a chemical compound of manganese, potassium and oxygen. The salt is also known as "permanganate of potash" and "Condy's crystals". In this salt, manganese is in the +7 oxidation state. The permanganate ion is a strong oxidizing agent. It dissolves in water to give deep purple solution, evaporation of which gives prismatic purple-black glistening crystals. It has a sweet taste and is odourless.
In 1659, German chemist J.R. Glauber, fused a mixture of the mineral pyrolusite and potassium carbonate to obtain a material that, when dissolved in water, gave a green solution potassium manganate (K2MnO4) which slowly changed colour to violet to form potassium permanganate and then finally red. This report has gone down in history as the first description of the production of potassium permanganate.
Around two hundred years later, London chemist Henry Bollmann Condy had an interest in disinfectants, and marketed several products including ozonised water. He found that fusing pyrolusite with Sodium Hydroxide (NaOH) and dissolved it in water produced a solution with disinfectant properties. He patented this solution, and marketed it as Condy's Fluid. Although effective, the solution was not very stable. This was overcome by using Potassium Hydroxide (KOH) rather than NaOH. This was more stable, and had the advantage of easy conversion to the equally effective Potassium Permanganate crystals.
This crystalline material was known as Condy’s crystals or Condy’s powder. Potassium Permanganate was comparatively easy to manufacture, so Condy was subsequently forced to spend considerable time in litigation in order to stop competitors from marketing products similar to Condy's Fluid or Condy's Crystals. However, Potassium Permanganate was born and the production started worldwide.
Grades are defined by the physical characteristics and purity of Potassium Permanganate. Different grades have different applications.
|Molar mass||158.04 g/mol|
|Appearance||Dark purple-bronze needles, Vivid purple in solution|
|Melting point||270 °C|
|Solubility in water||6.38 g/100 ml at 20 °C|