How to Prepare 10 Molar HCl Solution from a 37% HCl Stock Solution- A Step-by-Step Guide

How to Prepare 10 HCl Solution from 37 HCl

In various scientific and industrial applications, the preparation of a specific concentration of hydrochloric acid (HCl) solution is often required. One common scenario is the preparation of a 10% HCl solution from a stock solution of 37% HCl. This process involves diluting the concentrated acid with a suitable solvent, typically water. Below, we outline the steps to prepare a 10 HCl solution from 37 HCl.

Materials Needed

Before starting the preparation process, ensure you have the following materials:

– 37% HCl stock solution
– Distilled water
– Measuring cylinder
– Beaker
– Safety equipment (gloves, goggles, and lab coat)
– Stirrer

Step-by-Step Instructions

1. Safety Precautions: Wear appropriate safety equipment, including gloves, goggles, and a lab coat, to protect yourself from the hazards of HCl.

2. Determine the Volume of 37% HCl: Calculate the volume of 37% HCl needed to prepare 100 mL of 10% HCl solution. The formula for dilution is:

\[ C_1V_1 = C_2V_2 \]

Where:
– \( C_1 \) is the initial concentration (37%)
– \( V_1 \) is the initial volume (unknown)
– \( C_2 \) is the final concentration (10%)
– \( V_2 \) is the final volume (100 mL)

Rearranging the formula to solve for \( V_1 \):

\[ V_1 = \frac{C_2V_2}{C_1} \]

Plugging in the values:

\[ V_1 = \frac{10\% \times 100\, mL}{37\%} \approx 27.03\, mL \]

3. Measure the 37% HCl: Using a measuring cylinder, carefully measure out approximately 27.03 mL of the 37% HCl stock solution.

4. Add Water: In a beaker, add 73 mL of distilled water. It is crucial to add the acid to the water, not the other way around, to minimize the risk of splashing and to ensure proper dilution.

5. Add the 37% HCl to the Water: Slowly pour the measured 37% HCl into the beaker containing the water while stirring gently. Continue stirring to ensure even distribution of the acid.

6. Adjust the Volume: Once the solution is well mixed, use a measuring cylinder to add more distilled water if necessary to reach a final volume of 100 mL.

7. Final Check: Before using the 10% HCl solution, perform a final check to ensure the concentration is accurate. This can be done using a pH meter or by titrating the solution with a known base.

By following these steps, you can successfully prepare a 10% HCl solution from a 37% HCl stock solution. Always remember to prioritize safety and accuracy when handling chemicals in the laboratory.