PRAKTIKUM SEL ELEKTROLISIS | ELEKTROLISIS LARUTAN KI DENGAN ELEKTRODA KARBON (ELEKTRODA INERT)

Summary

In this educational video, Anita Day Hajar and her colleague demonstrate the electrolysis of potassium iodide (KI) solution using carbon electrodes. The experiment involves setting up a U-tube apparatus, connecting it to a power supply, and observing the reactions at both the anode and cathode. As the process unfolds, iodine is produced at the anode, while hydrogen gas forms at the cathode. Various tests confirm the presence of ions in the solution, showcasing the fundamental principles of electrolysis and the behaviors of different ions under electrical influence. This practical session aims to enhance understanding of electrochemical processes.

Takeaways

• 😀 The experiment involves the electrolysis of KI solution using carbon electrodes.
• 😀 Essential materials include a U-tube, carbon electrodes, a power supply, and various indicators.
• 😀 Electrodes must be cleaned with sandpaper before setup to ensure proper function.
• 😀 The U-tube should be securely mounted to avoid accidents during the experiment.
• 😀 KI solution is added to the U-tube up to a specific level before connecting the electrodes to the power supply.
• 😀 At the cathode, hydrogen gas bubbles indicate the reduction of water, forming hydrogen and hydroxide ions.
• 😀 Iodine is produced at the anode, indicated by an orange color, as iodide ions are oxidized.
• 😀 The presence of hydroxide ions is confirmed by adding phenolphthalein, resulting in a pink color change.
• 😀 The presence of iodine in the solution is confirmed by adding starch, which turns blue-black.
• 😀 The reactions at the electrodes depend on the nature of the electrolyte and the type of electrodes used.

Q & A

What is the main objective of the experiment described in the video?

The main objective is to conduct an electrolysis experiment using a potassium iodide (KI) solution with carbon electrodes.

What materials are required for the electrolysis experiment?

The required materials include a U-tube, carbon electrodes, a dropper, a power supply, PP or phenolphthalein indicator, starch solution, and a 0.5 molar potassium iodide solution.

What is the first step to prepare the electrodes for the experiment?

The first step is to clean both electrodes using sandpaper.

How should the U-tube be assembled on the stand?

The U-tube must be securely attached to the stand without being too loose or too tight to avoid it falling or breaking.

What occurs at the anode during the electrolysis of potassium iodide?

At the anode, orange color indicates the formation of iodine, which is the result of the oxidation of iodide ions.

What is observed at the cathode during the electrolysis process?

At the cathode, bubbles form, indicating the production of hydrogen gas due to the reduction of water.

How can the presence of hydroxide ions in the solution be confirmed?

The presence of hydroxide ions can be confirmed by adding phenolphthalein, which turns the solution pink, indicating a basic environment.

What test is used to confirm the presence of iodine in the solution?

The presence of iodine can be confirmed using a starch solution, which turns blue-black upon reaction with iodine.

What determines whether water or potassium ions will be reduced at the cathode?

The reduction process depends on the standard reduction potentials; in this case, water is reduced to hydrogen gas because it has a higher standard reduction potential than potassium ions.

What factors influence the reactions occurring at the anode during electrolysis?

The reactions at the anode are influenced by the type of electrode used—whether it is inert (like carbon) or reactive, determining which species will undergo oxidation.