Principles and Procedures of Chemical Experiments

Chemical Experiment on Neutralization Reactions

Objectives:

• To understand the concept of neutralization reactions
• To demonstrate the experimental procedures involved in neutralization reactions

Materials:

• Burette
• Pipette
• Conical flask
• Beaker
• Phenolphthalein solution (indicator)
• Sodium hydroxide solution
• Hydrochloric acid solution

Procedure:

1. Fill a burette with the sodium hydroxide solution.
2. Pipette 25 mL of the hydrochloric acid solution into a conical flask.
3. Add 2-3 drops of the phenolphthalein solution to the hydrochloric acid.
4. Slowly add the sodium hydroxide solution to the hydrochloric acid while swirling the flask.
5. Observe the color change of the solution.
6. Continue adding the sodium hydroxide solution until the solution turns a faint pink color.
7. Record the volume of sodium hydroxide solution used.

Key Procedures:

• Use a burette to accurately measure the volume of sodium hydroxide solution.
• Swirl the flask while adding the sodium hydroxide solution to ensure proper mixing.
• Add phenolphthalein indicator to the hydrochloric acid to visualize the endpoint of the reaction.
• The endpoint is reached when the solution turns a faint pink color.

Significance:

This experiment demonstrates the concept of neutralization reactions, which are important in various chemical processes, such as acid-base titrations, pH adjustments, and in the formulation of drugs and other products.