How to Prepare a 0.1M Ferric Chloride Solution: A Comprehensive Guide

Preparing a 0.1M ferric chloride (FeCl3·6H2O) solution for your lab experiments is a straightforward process when you follow the correct steps. Below, we will guide you through the necessary calculations and procedures, ensuring a safe and accurate final product.

Materials Needed

Ferric chloride hexahydrate (FeCl3·6H2O) Distilled water A balance for precise weighing A 1L volumetric flask or an appropriate size A stirring rod or magnetic stirrer for thorough dissolving A graduated cylinder for measuring

Calculation and Theory

First, let's calculate the molar mass of ferric chloride hexahydrate to ensure we have the right quantities.

The molar mass of FeCl3·6H2O is calculated as follows:

Molar Mass Calculation

Iron (Fe): 55.85 g/mol Chlorine (Cl): 35.45 g/mol (3 Cl atoms 3 × 35.45 g/mol 106.35 g/mol) Water (H2O): 18.02 g/mol (6 H2O molecules 6 × 18.02 g/mol 108.12 g/mol)

Total molar mass 55.85 106.35 108.12 270.32 g/mol.

To prepare 1 liter of a 0.1M FeCl3·6H2O solution, the mass required is calculated as:

Mass (g) Molarity (mol/L) × Molar mass (g/mol) × Volume (L)

Mass 0.1 mol/L × 270.32 g/mol × 1 L 27.032 g.

Procedure

Weigh out 27.032 grams of ferric chloride hexahydrate using the balance. Dissolve the ferric chloride in a small volume of distilled water, approximately 500 mL, in a beaker. Stir until the solution is completely dissolved. Transfer the solution to a 1L volumetric flask. Rinse the beaker with distilled water and add the rinse to the volumetric flask to ensure all the solute is transferred. Add distilled water to the volumetric flask until the total volume reaches the 1 L mark. Mix the solution thoroughly. Label the flask with the concentration and the date of preparation.

Safety Precautions

Wear gloves and goggles as ferric chloride can be corrosive and may cause skin and eye irritation. Work in a well-ventilated area or behind a fume hood if possible to avoid inhaling any fumes.

Now, you have successfully prepared a 0.1M ferric chloride solution for your lab needs.

Conclusion

By carefully following the steps provided, you can prepare a stable and accurate 0.1M ferric chloride solution. This process ensures safety, precision, and ensures the correct concentration for your experimental needs.