Explain the preparation of a desired molar solution providing step by step instruction
Preparing a desired molar solution involves determining the amount of solute and solvent required to achieve the desired concentration. Here are the step-by-step instructions:
1. Determine the desired molar concentration of the solution. For example, let's say we want to prepare a 1 M solution of sodium chloride (NaCl).
2. Calculate the amount of solute needed. This can be done using the formula:
- Weight of Solute (g) = Molar Concentration (mol/L) x Volume of Solution (L) x Molar Mass of Solute (g/mol)
In this case, let's say we want to prepare 1 liter of the 1 M NaCl solution, and the molar mass of NaCl is 58.44 g/mol. Therefore:
- Weight of NaCl (g) = 1 mol/L x 1 L x 58.44 g/mol = 58.44 g
So, we need 58.44 grams of NaCl for a 1 M solution.
3. Weigh out the calculated amount of solute (NaCl) using a laboratory balance and transfer it into a clean, dry container (such as a beaker or flask).
4. Add a small amount of distilled or deionized water to the container and stir until the solute is completely dissolved. This is to ensure that the solute is fully dissolved before adding more solvent.
5. Once the solute is dissolved, carefully transfer the solution to a volumetric flask. A volumetric flask has a specific volume and is commonly used for making precise measurements.
6. Rinse the container with more distilled or deionized water to make sure all of the solute is transferred to the volumetric flask.
7. Add enough distilled or deionized water to the volumetric flask to reach the final desired volume. In this case, we want a total volume of 1 liter, so add enough water to reach the mark on the flask.
8. Cap or stopper the flask and thoroughly mix the solution by inverting it several times. This ensures that the solute is evenly distributed throughout the solution.
9. Lastly, label the flask with the details of the solution, including the name of the solute (NaCl), the concentration (1 M), and the date of preparation.
By following these steps, you can prepare a desired molar solution accurately and efficiently.