Preparation of 0.1 M Hydrochloric Acid Solution

To prepare a 0.1 M hydrochloric acid (HCl) solution, you dilute concentrated HCl (approximately 36-38% w/w, ~12 M) with distilled water. Using the formula M1​V1​=M2​V2​, calculate the required volume of concentrated HCl as 8.33 mL for 1 liter of 0.1 M solution. Begin by wearing appropriate safety gear and working in a ventilated area. Add about 800 mL of distilled water to a 1-liter volumetric flask, then carefully add the 8.33 mL of concentrated HCl to the water (always add acid to water to avoid exothermic reactions). Mix thoroughly and top up with distilled water until the volume reaches 1 liter. Label the container with “0.1 M HCl” and the preparation date, and store it in a clean, sealed container. For precise analytical work, standardize the solution to ensure accurate molarity.

Preparation of 0.1 M Hydrochloric Acid Solution

To prepare a 0.1 M HCl solution, you need to dilute concentrated hydrochloric acid with water. Here’s the step-by-step procedure:

Materials Needed

1. Concentrated Hydrochloric Acid (HCl, approximately 36-38% w/w, density ~1.18 g/mL).
2. Distilled or deionized water.
3. 1-liter volumetric flask.
4. Measuring cylinder or pipette.
5. Safety equipment (gloves, goggles, lab coat).

Calculation for Volume of Concentrated HCl

The relationship between concentration and volume is given by the formula:

M1​V1​=M2​V2​

Where:

• M1: Concentration of concentrated HCl (typically ~12 M for 36-38% HCl).
• V1: Volume of concentrated HCl to be used.
• M2: Desired concentration (0.1 M).
• V2: Final volume of the solution (1 liter = 1000 mL).

Substituting the values:

12×V1​=0.1×1000

V1​=0.1×1000/12​=8.33mL

You need 8.33 mL of concentrated HCl to prepare 1 liter of 0.1 M HCl solution.

Procedure

1. Safety First: Wear gloves, goggles, and a lab coat. Work in a well-ventilated area or fume hood.
2. Measure Concentrated HCl: Use a pipette or a measuring cylinder to accurately measure 8.33 mL of concentrated HCl.
3. Dilution:
   • Add about 800 mL of distilled water to a clean 1-liter volumetric flask.
   • Slowly add the measured concentrated HCl to the water. Always add acid to water, not water to acid, to avoid exothermic reactions.
4. Mix: Swirl the flask gently to mix the solution.
5. Adjust Volume:
   • Add more distilled water to the flask until the bottom of the meniscus reaches the 1-liter mark.
   • Mix thoroughly to ensure a homogeneous solution.
6. Label: Clearly label the container with “0.1 M HCl” and the preparation date.

Storage

Store the solution in a clean, labeled, and tightly sealed container. Ensure proper storage away from incompatible substances.

Note

• The actual concentration of commercial HCl may vary. Always check the label and adjust calculations if necessary.
• Standardize the prepared solution if precise molarity is critical for analytical applications.