Preparation of 0.1 N HCl Solution
Introduction
Hydrochloric acid (HCl) is a strong acid widely used in various fields such as chemistry, biology, and medicine. In laboratory settings, HCl solutions are commonly used as a reagent or solvent. In this article, we will discuss the preparation of 0.1 N HCl solution, which is a common concentration used in many laboratory procedures.
Materials
- Hydrochloric acid (HCl) 37% (w/v)
- Distilled water
- Volumetric flask (100 mL)
- Pipettes
- Balance
Preparation
To prepare 0.1 N HCl solution, follow these steps:
Step 1: Calculate the Volume of HCl Needed
To prepare 100 mL of 0.1 N HCl solution, calculate the volume of HCl needed using the following formula:
Volume of HCl (mL) = (Normality of HCl x Volume of solution) / Concentration of HCl
where:
- Normality of HCl = 0.1 N
- Volume of solution = 100 mL
- Concentration of HCl = 37% (w/v) = 11.4 M
Volume of HCl (mL) = (0.1 N x 100 mL) / 11.4 M = 8.77 mL
Step 2: Measure the Volume of HCl
Using a pipette, accurately measure 8.77 mL of 37% HCl.
Step 3: Dilute the HCl with Distilled Water
Transfer the measured HCl to a 100 mL volumetric flask and add distilled water up to the mark. Mix well to ensure complete dilution.
Step 4: Verify the Concentration
Using a pH meter or pH paper, verify that the prepared solution has a pH close to 1, which corresponds to 0.1 N HCl.
Tips and Precautions
- Always handle HCl with caution, as it is a corrosive and hazardous substance. Wear protective gloves, goggles, and lab coats when handling HCl.
- Ensure the volumetric flask and pipettes are clean and dry before use to prevent contamination.
- Prepare the solution in a well-ventilated area, and avoid inhaling HCl fumes.
- Label the prepared solution clearly and store it in a designated area.
Conclusion
Preparation of 0.1 N HCl solution is a straightforward process that requires attention to detail and caution when handling HCl. By following these steps and taking necessary precautions, you can ensure a safe and accurate preparation of this commonly used laboratory reagent.