Preparation and Standardization of Potassium Permanganate

Here is a detailed discussion on How to Prepare and Standardization of Potassium Permanganate (1M, 0.1M, 1N, 0.1N) solution by using different reagents in Labs.

Preparation and Standardization of 1M Potassium Permanganate

Potassium permanganate – M.Wt – 158

Preparation of 1M Solution of Potassium Permanganate:

• Dissolve an accurately weighed 158 gm of KMnO₄ in 900 ml of water.
• Heat it in a water bath for 1 hour, cool it, then filter it using a sintered glass filter.
• Add enough water to make it 1000 ml.

Principle: In volumetric analysis, many reactions involve oxidation and reduction. An oxidizing agent is estimated by titrating with a reducing agent and vice versa. These titrations are called redox titrations. Standardizing KMnO₄ is an example of a redox titration. KMnO4 is a strong oxidizing agent and, in an acidic medium, it oxidizes oxalic acid to CO₂.

2KMnO₄ + 3H₂SO₄ + 5H₂C₂O₄ → K2SO₄ + 2MnSO₄ + 8H₂O + 10CO₂

The temperature is maintained at 60˚-70˚ C during titration because the reaction is slow at room temperature. No indicator is needed as KMnO₄ is a self-indicator.

Preparation of 1M Oxalic Acid Solution: Dissolve an accurately weighed 126.07 gm of Oxalic acid in enough water to make 1000 ml.

Procedure for Standardization of 1M KMnO₄:

Pipette out exactly 10 ml of 1M Oxalic acid solution into a clean conical flask. Add 10 ml of diluted H2SO₄. Warm the flask contents to 70˚C and titrate with KMnO₄ solution. Continue titration until a faint pink color appears. Repeat for concordant values and record in a table.

Calculation of Molarity of KMnO4:

Use the formula M₁V₁ = M₂V₂
where V₁ = Volume of 1M Oxalic acid solution (10 ml)
M₁ = Molarity of Oxalic acid solution (1M)
V₂ = Volume of KMnO₄ solution used (from the average burette reading)
M₂ = Molarity of KMnO₄ (To be Find Out).

Calculate M₂=

Preparation and Standardization of 0.1M KMnO₄:

To make 0.1M Potassium Permanganate, follow these steps:

• Take 15.8 grams of KMnO₄, put it in 900 ml of water, and heat it in a water bath for an hour.
• Let it cool, then filter it with a sintered glass filter.
• Add enough water to make it 1000 ml.

Principle: In a Lab, when we analyze volumes, we often deal with oxidation and reduction processes. Oxidizing agents are measured by titrating with reducing agents, and vice versa. This type of titration is called redox titration. Standardizing KMnO₄ is an example of redox titration. KMnO₄ is a strong oxidizing agent; in an acidic environment, it turns oxalic acid into CO₂.

2KMnO₄ + 3H₂SO₄ + 5H₂C₂O₄ → K₂SO₄ + 2MnSO₄ + 8H₂O +10CO₂

During the titration, keep the temperature between 60˚-70˚ C, because the reaction is slow at room temperature. KMnO₄ itself serves as an indicator, so no additional indicator is needed.

Preparation of 0.1M Oxalic Acid Solution: Dissolve 12.6 grams of Oxalic Acid in enough water to make 1000 ml.

Standardization of 0.1M KMnO4:

• Take exactly 10 ml of 0.1M Oxalic Acid, put it in a clean flask, add 10 ml of dilute H₂SO₄, warm it to 70˚C, and titrate with KMnO₄.
• Keep titrating until you see a faint pink color.
• Repeat for consistent results and record them in a table.

Use the formula M₁V₁ = M₂V₂ to calculate the Molarity of KMnO₄:

V₁ (Volume of Oxalic Acid) = 10 ml
M₁ (Molarity of Oxalic Acid) = 0.1M
V₂ (Volume of KMnO₄) = Average Burette Reading
M₂ (Molarity of KMnO₄) =?

Preparation and Standardization of 1N Potassium permanganate :

To make a 1N Potassium permanganate solution, follow these steps:

• Take 31.6 grams of KMnO₄ and dissolve it in 900 ml of water.
• Heat the mixture in a water bath for an hour, let it cool, then filter it using a sintered-glass filter.
• Finally, add enough water to obtain the total volume to 1000 ml.

Principle: In volumetric analysis, certain reactions involve oxidation and reduction. We estimate the strength of an oxidizing agent by titrating it with a reducing agent and vice versa. These titrations are known as redox titrations. The standardization of KMnO₄ is an example of a redox titration. KMnO₄ is a strong oxidizing agent, and in an acidic medium, it oxidizes oxalic acid to produce CO₂.

2KMnO₄ + 3H₂SO₄ + 5H₂C₂O₄ → K₂SO₄ + 2MnSO₄ + 8H₂O +10CO₂

The titration should be performed at a temperature of 60-70˚ C because the reaction is slow at room temperature. No indicator is needed as KMnO₄ acts as a self-indicator.

Prepare 1N Oxalic Acid Solution: Dissolve 63.035 grams of Oxalic acid in enough water to make 1000 ml of solution.

Standardize 1N KMnO₄ with Oxalic Acid:

• Pipette exactly 10 ml of 1N Oxalic acid solution into a clean flask.
• Add 10 ml of diluted H₂SO₄. Warm the mixture to 70˚C and titrate with KMnO₄ solution.
• Stop titrating when a faint pink color appears.
• Repeat the titration for consistent values, recording them in a tabular form.

We use a formula – N₁V₁ = N₂V₂ – to figure out how strong our potassium permanganate is.

N₁ is the strength of oxalic acid (it’s 1N).
V₁ is the amount we used (it’s 10 ml).
N₂ is what we’re figuring out.
V₂ is how much potassium permanganate we used (To be Calculated).

Preparation and Standardization of 0.1N Potassium permanganate :

Potassium permanganate – M.Wt – 158

Potassium permanganate has a molecular weight of 158. Below is the process of how you can make a 0.1N solution:

• Take 3.16 grams of KMnO₄ and dissolve it in 900 ml of water.
• Heat it in a water bath for an hour, let it cool, then filter it using a special filter.
• Add enough water to make it 1000 ml.

Now, in simple terms, we often use a process called redox titration to figure out the amount of one substance by reacting it with another. In this case, we’re standardizing KMnO₄, which is a strong oxidizing agent.

2KMnO₄ + 3H₂SO₄ + 5H₂C₂O₄ → K₂SO₄ + 2MnSO₄ + 8H₂O +10CO₂

During the process, we keep the temperature at 60-70°C, because the reaction is a bit slow at room temperature. No need for an indicator as KMnO₄ acts as an indicator.

Preparation of 0.1N solution of oxalic acid: Make a 0.1N solution of oxalic acid by dissolving 6.3 grams in enough water to make 1000 ml.

Standardization of 0.1N Potassium permanganate:

• Take exactly 10 ml of this oxalic acid solution in a flask, add 10 ml of dilute sulfuric acid, warm it to 70 degrees Celsius, and titrate it with KMnO₄ solution until you see a faint pink color.
• Repeat this process for accuracy and record your values in a table.

To find the normality of KMnO4, use the formula: N₁V₁ = N₂V₂.

Here, V₁ is the volume of the oxalic acid solution (10 ml)
N₁ is its normality (0.1N)
V₂ is the volume of the KMnO₄ solution used
N₂ is what we want to find.

Next, Preparation and Standardization of 0.02M Potassium Permanganate “Will Update soon”