Preparation of 0.1 N Sodium Hydroxide (NaOH) Solution
Sodium hydroxide (NaOH) is a strong base widely used in various chemical reactions, laboratory experiments, and industrial applications. A 0.1 N (normal) sodium hydroxide solution is a common concentration used in many applications, including titration, pH adjustment, and sample preparation. In this article, we will discuss the preparation of 0.1 N sodium hydroxide solution.
Materials Needed
- Sodium hydroxide (NaOH) pellets or granules
- Distilled water
- 1-liter volumetric flask
- Graduated cylinder or pipette
- pH meter or pH paper (optional)
Preparation Procedure
Step 1: Calculate the Amount of NaOH Needed
To prepare a 0.1 N sodium hydroxide solution, you need to calculate the amount of NaOH required. The normality of a solution is defined as the number of equivalents of solute per liter of solution. For NaOH, one equivalent is equal to one mole (40 g) of NaOH.
For a 0.1 N NaOH solution, you need:
- 0.1 equivalents/L × 40 g/equivalent = 4 g of NaOH per liter of solution
Step 2: Weigh the NaOH
Accurately weigh 4 g of sodium hydroxide (NaOH) pellets or granules using a balance or scale.
Step 3: Dissolve the NaOH in Water
Transfer the weighed NaOH to a 1-liter volumetric flask. Add a small amount of distilled water (about 100-200 mL) to the flask and swirl gently to dissolve the NaOH. You may need to heat the mixture slightly to facilitate dissolution.
Step 4: Dilute the Solution to the Mark
Once the NaOH is dissolved, add more distilled water to the flask until the volume reaches the 1-liter mark.
Step 5: Mix and Verify the Solution
Mix the solution thoroughly to ensure uniform concentration. If desired, you can verify the pH of the solution using a pH meter or pH paper to ensure it is within the expected range (pH 12-13).
Tips and Precautions
- Always handle sodium hydroxide with caution, as it is a strong base that can cause skin and eye irritation.
- Wear protective gloves, goggles, and lab coats when handling NaOH.
- Use a fume hood or well-ventilated area to prepare the solution, as NaOH can release harmful fumes when reacting with water.
- Store the prepared 0.1 N NaOH solution in a tightly sealed container, away from direct sunlight and heat sources.
By following these simple steps, you can prepare a 0.1 N sodium hydroxide solution for your laboratory or industrial needs.
