Oxidation titration using KMnO4 is a common laboratory technique used to determine the concentration of an oxidising agent in a solution. This method is also known as a self-indicator titration because the KMnO4 solution itself acts as the indicator. In this blog post, we will discuss the principles behind this titration method and provide some tips for carrying it out successfully.
What is an Oxidation Titration?
Oxidation is a reaction in which electrons are lost from an atom or molecule. This can happen when a substance reacts with oxygen, as in the case of rusting metal. Oxidation titration is a way of measuring the amount of oxidising agent present in a solution. The most common oxidising agent used in this type of titration is the KMnO4 solution.
Why is KMno₄ a Self Indicator?
Kmno₄ is a self indicator because it changes colour when it reacts with oxygen. This makes it easy to tell when the reaction is complete and the titration is finished.
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Uses of Kmno4
Potassium Permanganate (KMno4) has several uses. It can be used to:
-As a disinfectant
-For water treatment
-In dyeing and printing fabrics
-As an oxidising agent
-In analytical chemistry
Kmno4 is also used in many industries:
-Pulp and paper
-Textile
-Petrochemical industry
-Water treatment
Theory of Potassium Permanganate: Kmno4 Solution
KMnO4 Solution is a self indicator because it is a powerful oxidising agent. When sulphuric acid is present in the KMnO4 solution, it is oxidised to sulphuric acid. This change in colour is used to indicate the endpoint of the solution. As per the acid solution MnO4-4 is a greenish-brown colour, when it is mixed with the acid, the colour changes to deep purple. This change in colour is used to indicate the endpoint of the solution.
– KMnO4 is a powerful oxidising agent
– KMnO4 changes colour in presence of acid to indicate the endpoint of the solution
– KMnO4 is used as an indicator in titration because it is a self indicator.
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Material Required to Conduct Oxidation Titration Using KMnO4 Solution
– KMnO4 sample solution: This will be the solution that you are going to titrate. To prepare this, take your unknown and dissolve it in a small volume of water.
– KMnO4 titrant solution: This is the standard KMnO₄ solution. In preparation, take the KMnO₄ and dissolve it in water to make a 0.02 M solution.
– Buret: This is where you will place the KMnO4 titrant solution.
– Erlenmeyer flask: This is where you will place the KMnO4 sample solution.
– Pipette: This is used to transfer a small volume of the KMnO4 sample solution into the Erlenmeyer flask.
– Stirring rod: This is used to stir the contents of the Erlenmeyer flask.
– White tile: This is used as a backdrop to see the colour change of the kmno_sample solution.
– Phenolphthalein indicator: This is used to determine the endpoint of the titration.
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Procedure to Perform Oxidation Titration Using KMnO4 Solution
To begin, take your KMnO4 sample solution and pipette a small volume into the Erlenmeyer flask. To this, add an equal volume of water and swirl the contents to mix. Next, take your KMnO4 indicator solution and add one drop to the flask contents. Swirl to mix. The KMnO4 indicator is a self-indicator; it will change colour in the presence of the KMnO4 sample. When the colour changes from light pink to deep purple, you have reached the endpoint of the titration and can stop adding KMnO4 indicator. Record the volume of the KMnO4 indicator added. Finally, take your KMnO4 titrant solution and add it dropwise to the flask contents, swirling after each addition, until the colour changes from light pink to deep purple. Record the volume of KMnO4 titrant used.
Titration With KMnO4
Titration is the process of adding a measured volume of one solution (the titrant) to another until the chemical reaction between them is just complete. The endpoint of the titration is usually indicated by a colour change. KMnO4-2 is a self-indicator for titrations with KMnO4. This is because the deep pink colour of the permanganate ion changes to a paler pink in the presence of MnO42- ions. The change in colour is not always easy to see, so a more reliable way to find the endpoint is by using an indicator.
An indicator is a substance that changes colour in the presence of the ions that are taking part in the reaction. The endpoint of the titration is when the indicator changes colour. The most common indicators used in acid-base titrations are a universal indicator, phenolphthalein and methyl orange.
When using KMnO4 as the titrant, the endpoint is reached when the solution changes from pink to colourless. The solution is then titrated until it reaches the endpoint. The volume of KMnO4 required to reach the endpoint is known as the endpoint volume.
Conclusion
Titration is a common method used in chemistry to determine the concentration of a solution. In an oxidation titration, the KMnO4 solution is used as a self-indicator to determine the concentration of the KMnO4 sample. This method is accurate and easy to use, making it a popular choice for many chemists. This article deals in detail what is an oxidation reaction, all about the KMnO4 solution, and titration with KMnO4. If you’re interested in learning more about oxidation titrations using KMnO4, be sure to check our articles.