PRAKTIKUM LKPD 1 (PRINSIP LARUTAN PENYANGGA)

Summary

This video demonstrates an experiment to explore the principles of buffer solutions by testing the pH of soda and tea. The process involves adding hydrochloric acid (HCl), sodium hydroxide (NaOH), and distilled water to samples of both beverages. The pH of the solutions is measured before and after each addition using universal pH indicator paper. The video explains the changes in pH after adding acid, base, and diluting with water, providing insights into how buffer solutions function in stabilizing pH levels in liquids like soda and tea. The experiment concludes with a summary of the pH changes observed.

Takeaways

• 😀 The experiment involves testing the pH of soda and tea before and after the addition of acids, bases, and dilution.
• 😀 Universal pH indicator paper is used to measure the pH of both the soda and tea samples.
• 😀 The experiment requires materials such as beakers, pipettes, HCl (0.1 M), NaOH (0.1 M), and distilled water.
• 😀 The first step is to prepare 30 ml of soda in a beaker and allow the fizz to subside before measuring its pH.
• 😀 The pH of the soda is initially measured by dipping universal pH indicator paper into the solution.
• 😀 The soda is then divided into three beakers, each receiving different treatments: addition of HCl, NaOH, or dilution with distilled water.
• 😀 5 drops of 0.1 M HCl are added to the first beaker of soda, and the pH is measured again.
• 😀 5 drops of 0.1 M NaOH are added to the second beaker of soda, followed by another pH measurement.
• 😀 The third beaker receives 5 ml of distilled water to dilute the soda, and the pH is checked once more.
• 😀 The same steps are repeated for tea, using 30 ml of tea and following the same procedure with acid, base, and dilution treatments.
• 😀 The pH values are recorded after each treatment to observe how the acid, base, and dilution affect the pH of the beverages.

Q & A

What is the main objective of the experiment in the script?

The main objective of the experiment is to demonstrate the principles of buffer solutions and how different substances affect the pH levels of beverages like soda and tea.

What are the materials needed for the experiment?

The materials needed include pipette droppers, universal indicator paper, four chemical beakers, a 10 ml measuring cup, laboratory coat, soda, hydrochloric acid (HCl), sodium hydroxide (NaOH), distilled water (aquades), and tea.

What is the first step of the experiment with soda?

The first step is to pour 30 ml of soda into a chemical beaker and wait for a few moments to let the fizzing disappear.

How is the pH of the soda measured?

The pH of the soda is measured by dipping a piece of universal indicator paper into the soda and comparing the color change to the pH chart provided.

What are the different substances added to the soda in the experiment?

Three substances are added to the soda: hydrochloric acid (HCl), sodium hydroxide (NaOH), and distilled water (aquades).

What happens when HCl is added to the soda in the experiment?

When HCl is added to the soda, the pH decreases, which is measured using the universal indicator paper.

How is the pH affected when NaOH is added to the soda?

When NaOH is added to the soda, the pH increases, as measured by the universal indicator paper.

What role does distilled water play in the experiment?

Distilled water (aquades) is used for dilution in the experiment. It is added to one of the beakers to lower the concentration of the soda, thereby affecting the pH level.

How is the pH measured after the addition of each substance to the soda?

After each substance is added (HCl, NaOH, or distilled water), the pH is measured by dipping universal indicator paper into the solution and comparing the color change to the provided pH chart.

What is the significance of the tea sample in the experiment?

The tea sample is used to perform a similar pH measurement experiment as the soda. The tea is divided into three parts, and HCl, NaOH, or distilled water is added to observe how each affects the pH level.