0.1 M Phosphoric Acid Preparation
Phosphoric acid (H3PO4) is a strong acid widely used in various laboratory applications, including chromatography, biochemical research, and pharmaceutical manufacturing. Preparing a 0.1 M phosphoric acid solution is a common task in many laboratories. In this article, we will guide you through the steps to prepare a 0.1 M phosphoric acid solution.
Materials Needed
- Phosphoric acid (H3PO4) (85% w/w)
- Distilled water
- A 100 mL or 1 L volumetric flask
- A pipette or measuring cylinder
- A balance or scale
Preparation of 0.1 M Phosphoric Acid Solution
Step 1: Calculate the Amount of Phosphoric Acid Needed
To prepare a 0.1 M phosphoric acid solution, you need to calculate the amount of phosphoric acid required. The molar mass of phosphoric acid (H3PO4) is 97.97 g/mol. To prepare 1 liter of a 0.1 M solution, you need:
0.1 mol/L x 1 L = 0.1 mol
0.1 mol x 97.97 g/mol = 9.797 g
So, you need approximately 9.8 g of phosphoric acid for 1 liter of a 0.1 M solution.
Step 2: Weigh the Phosphoric Acid
Using a balance or scale, weigh out approximately 9.8 g of phosphoric acid (H3PO4) into a beaker or a weighing boat.
Step 3: Add Phosphoric Acid to the Volumetric Flask
Using a pipette or measuring cylinder, transfer the weighed phosphoric acid into a 1 L volumetric flask.
Step 4: Add Distilled Water
Slowly add distilled water to the volumetric flask while gently stirring the mixture with a glass rod or a stirrer. Continue adding water until the volume reaches 1 L.
Step 5: Mix and Label the Solution
Mix the solution thoroughly to ensure the phosphoric acid is fully dissolved. Label the flask with the solution's concentration (0.1 M phosphoric acid), the date, and your name or initials.
Tips and Precautions
- Always handle phosphoric acid with caution, as it is a corrosive and toxic substance. Wear protective gloves, goggles, and a lab coat when handling the acid.
- Store the 0.1 M phosphoric acid solution in a tightly sealed container in a cool, dry place.
- Phosphoric acid solutions are prone to contamination, so it is essential to use distilled water and ensure the equipment is clean and free of contaminants.
By following these steps, you can prepare a 0.1 M phosphoric acid solution accurately and safely. Remember to handle the acid with caution and store the solution properly to ensure its stability and effectiveness in your laboratory applications.
