How to Prepare 100 mL of 0.75 M HCl Solution Using 6.0 M HCl: A Detailed Guide

Understanding how to prepare specific concentrations of Hydrochloric Acid (HCl) solutions is crucial in various scientific and industrial applications. In this article, we will explore the process of diluting a more concentrated 6.0 M HCl solution to achieve a less concentrated 0.75 M HCl solution, all while adhering to the dilution formula V1C1 V2C2.

Understanding the Concentration Factors

First, it is important to recognize the concentration factors involved. A 6.0 M HCl solution is 8 times more concentrated compared to a 0.75 M HCl solution. This difference in concentration necessitates the use of a dilution factor of 8 (calculated from 6 / 0.75).

Applying the Dilution Formula

The dilution formula V1C1 V2C2 is a fundamental equation for preparing solutions of specific concentrations. Here, V1 is the initial volume of the more concentrated solution, C1 is the initial concentration, V2 is the final volume, and C2 is the final concentration.

Given Data and Initial Calculations

The given data for our problem includes:

Initial volume (V1): unknown Initial concentration (C1): 6.0 M Final volume (V2): 100 mL Final concentration (C2): 0.75 M

Substituting these values into the formula V1C1 V2C2, we get:

V1 V2C2 / C1

V1 100 mL x 0.75 M / 6.0 M

V1 12.5 mL

Alternative Calculation Method

Alternatively, we can also determine the initial volume by using the dilution factor. Since the initial concentration is 8 times that of the final concentration, we can simply divide the final volume by 8:

100 mL / 8 12.5 mL

Preparation Method

Here is a step-by-step guide to preparing 100 mL of 0.75 M HCl solution using 6.0 M HCl:

Accurately measure 12.5 mL of 6.0 M HCl solution. Use a calibration pipette or a 12.5 mL measuring cylinder to ensure precise volume measurement. Transfer this measured solution into a 100 mL volumetric flask. Ensure that the acid is thoroughly mixed with the flask. Add distilled or deionized water to the volumetric flask and fill it to the 100 mL mark. Make sure the solution is well mixed to ensure uniform concentration. Shake the flask gently to ensure complete mixing of the solution. Alternatively, you can use a magnetic stirrer for more uniform mixing.

Handling and Safety Precautions

Always handle HCl solutions with caution, as they are highly corrosive and can cause severe burns. Wear appropriate personal protective equipment such as gloves, goggles, and a lab coat. Ensure the solution is prepared in a well-ventilated area to avoid inhaling fumes.

Conclusion

By leveraging the dilution formula V1C1 V2C2 and understanding the concentration factors involved, it is straightforward to prepare a 100 mL solution of 0.75 M HCl from a 6.0 M stock solution. The key steps include accurate volume measurement and proper mixing techniques. Always prioritize safety during the preparation process.