Prepare 250 cc n/10 KMno4 solution
To prepare a 250 cc n/10 KMnO4 solution, you will need the following:
1. KMnO4 crystals: Obtain potassium permanganate (KMnO4) crystals from a chemical supplier. Ensure that the KMnO4 is of sufficient purity for your intended use.
2. Water: You will need purified or distilled water for this solution. Make sure the water is free from impurities that might affect the accuracy of your n/10 KMnO4 solution.
Now, let's proceed step by step to prepare the solution:
Step 1: Calculate the mass of KMnO4 required:
The molar mass of KMnO4 is approximately 158.034 g/mol. To prepare a 250 cc (or 250 mL) solution, you need to calculate the mass of KMnO4 required using the formula:
Mass (g) = (Volume (cc) × Molarity (M) × Molar mass (g/mol)) / 1000
For an n/10 KMnO4 solution:
Molarity (M) = 10^-1 (since n/10 is the same as 1/10 or 0.1)
Volume (cc) = 250 cc
Molar mass (g/mol) = 158.034 g/mol
Mass (g) = (250 cc × 0.1 M × 158.034 g/mol) / 1000
Mass (g) = 3.951 g (to three decimal places)
Step 2: Dissolve KMnO4 crystals:
Measure approximately 3.951 grams of KMnO4 crystals using a weighing balance and transfer them into a clean and dry beaker.
Step 3: Add water and dissolve:
Now, slowly add purified or distilled water to the beaker while stirring gently with a glass rod or a magnetic stirrer. Continue stirring until the KMnO4 crystals completely dissolve. Make sure the resulting solution reaches a final volume of 250 cc. Ensure that the beaker and stirring rod are clean and free from any contaminants.
Step 4: Transfer and store:
After complete dissolution, transfer the solution to a clean, sterile, airtight container such as a glass bottle or a reagent bottle. Ensure that the container is properly labeled with the concentration, date, and any necessary safety warnings.
Congratulations! You have prepared a 250 cc n/10 KMnO4 solution. Remember to handle and store the solution with care, following any safety guidelines, as KMnO4 can be hazardous.