Potassium permanganate and hydrogen peroxide titration, a fundamental technique in analytical chemistry, offers a precise and versatile method for determining the concentration of unknown solutions. This guide delves into the principles, procedures, applications, and safety considerations of this essential technique.

Potassium permanganate, a powerful oxidizing agent, reacts with hydrogen peroxide in a redox reaction, resulting in a distinct color change from purple to colorless. This color change serves as the endpoint of the titration, allowing for accurate determination of the unknown solution’s concentration.

Potassium Permanganate and Hydrogen Peroxide Titration

Potassium permanganate and hydrogen peroxide titration is a quantitative analytical technique used to determine the concentration of an unknown solution by reacting it with a known solution of potassium permanganate.

Potassium permanganate is a strong oxidizing agent that reacts with hydrogen peroxide in an acidic solution to produce manganese dioxide, water, and oxygen. The reaction is represented by the following equation:

KMnO₄+ 5H ₂O ₂+ 3H ₂SO ₄→ 2MnSO ₄+ K ₂SO ₄+ 8H ₂O + 5O ₂

Materials and Equipment

• Potassium permanganate solution (0.02 M)
• Hydrogen peroxide solution (0.1 M)
• Sulfuric acid (1 M)
• Burette
• Pipette
• Erlenmeyer flask
• Magnetic stirrer

Procedure

1. Pipette 25 mL of the unknown hydrogen peroxide solution into an Erlenmeyer flask.
2. Add 10 mL of 1 M sulfuric acid to the flask.
3. Fill a burette with the potassium permanganate solution.
4. Slowly add the potassium permanganate solution to the hydrogen peroxide solution while stirring constantly.
5. Observe the color of the solution as you add the potassium permanganate solution.
6. Continue adding the potassium permanganate solution until the solution turns a faint pink color that persists for at least 30 seconds.
7. Record the volume of potassium permanganate solution used.

Observations and Calculations, Potassium permanganate and hydrogen peroxide titration

The color of the solution will change from colorless to purple as the potassium permanganate solution is added. As the reaction progresses, the purple color will gradually fade until it reaches a faint pink endpoint.

The concentration of the unknown hydrogen peroxide solution can be calculated using the following equation:

M₁V ₁= M ₂V ₂

where:

• M ₁is the concentration of the potassium permanganate solution (0.02 M)
• V ₁is the volume of the potassium permanganate solution used (in mL)
• M ₂is the concentration of the unknown hydrogen peroxide solution (in M)
• V ₂is the volume of the unknown hydrogen peroxide solution (in mL)

Applications

Potassium permanganate and hydrogen peroxide titration is used in a variety of applications, including:

• Determining the concentration of hydrogen peroxide in commercial products
• Analyzing the antioxidant content of foods and beverages
• Measuring the dissolved oxygen content of water
• Titrating reducing agents, such as ascorbic acid (vitamin C)

Safety Precautions

Potassium permanganate and hydrogen peroxide are both corrosive and can cause skin and eye irritation. It is important to wear gloves and eye protection when handling these chemicals. Potassium permanganate can also stain clothing and surfaces, so it is important to be careful when using it.

Potassium permanganate and hydrogen peroxide should be disposed of properly according to local regulations.

FAQ Corner: Potassium Permanganate And Hydrogen Peroxide Titration

What is the purpose of potassium permanganate and hydrogen peroxide titration?

Potassium permanganate and hydrogen peroxide titration is used to determine the concentration of an unknown solution by measuring the volume of a known solution required to react completely with it.

What is the endpoint of the titration?

The endpoint of the titration is the point at which the reaction between potassium permanganate and hydrogen peroxide is complete, as indicated by a distinct color change from purple to colorless.

What are the safety precautions that should be followed when handling potassium permanganate and hydrogen peroxide?

Potassium permanganate and hydrogen peroxide are corrosive and can cause skin irritation. Proper protective gear, such as gloves and eye protection, should be worn when handling these chemicals.