Corrosion : Electrochemical Cell or Corrosion Cell (Chapter 3) (Animation)

Summary

This video explains the concept of corrosion as an electrochemical process where metals degrade due to electron transfer between two electrodes. It describes the electrochemical cell, where oxidation occurs at the anode, releasing electrons that travel through a metallic path to the cathode, where a reduction reaction takes place. The video highlights the essential components of an electrochemical cell: the anode, cathode, metallic path, and electrolyte. The corrosion process is accelerated when these elements are present, and it demonstrates how corrosion affects metals, with examples like iron and copper.

Takeaways

• 😀 Corrosion is the degradation of metals due to an electrochemical process.
• 😀 An electrochemical process involves the transfer of electrons between two electrodes in an electrochemical cell.
• 😀 Understanding corrosion requires knowledge of electrochemical or corrosion cells.
• 😀 An electrochemical cell converts chemical energy into electrical energy.
• 😀 Electrons liberated by oxidation at the anode travel through a conductor to the cathode, where they are consumed by reduction reactions.
• 😀 The four components of an electrochemical cell are anode, cathode, metallic path, and electrolyte.
• 😀 The anode undergoes oxidation, causing the metal to lose mass and corrode.
• 😀 The metallic path allows electrons to flow from the anode to the cathode.
• 😀 Reduction reactions occur at the cathode, where electrons are consumed.
• 😀 Electrolytes, which contain charged ions, are necessary for corrosion to occur.
• 😀 In the given example, iron loses electrons at the anode, and copper is reduced at the cathode, leading to the deposition of copper metal.

Q & A

What is corrosion and how is it defined in the context of electrochemical processes?

Corrosion is the degradation of metals due to an electrochemical process. It involves a chemical reaction where electrons are transferred between two electrodes in an electrochemical cell.

What is an electrochemical process?

An electrochemical process is a chemical reaction involving the transfer of electrons between two electrodes in an electrochemical cell, converting chemical energy into electrical energy.

What is the role of an electrochemical or corrosion cell in corrosion?

An electrochemical or corrosion cell is a device that converts chemical energy into electrical energy. It is essential for the occurrence of corrosion as it involves the transfer of electrons between the anode and cathode, leading to metal degradation.

What are the fundamental components of an electrochemical cell?

The fundamental components of an electrochemical cell are the anode, cathode, metallic path, and electrolyte. All four components must be present for corrosion to occur.

What happens at the anode in an electrochemical cell during corrosion?

At the anode, a metal is oxidized, causing it to lose mass and corrode. This oxidation process releases electrons that travel to the cathode through a metallic path.

What is the function of the metallic path in an electrochemical cell?

The metallic path allows the electrons produced by oxidation at the anode to travel to the cathode, completing the circuit necessary for the electrochemical process.

What occurs at the cathode in an electrochemical cell?

At the cathode, reduction takes place where electrons are consumed in a reaction. This is where the electrons from the anode are used to reduce ions or other species in the electrolyte.

What is the role of the electrolyte in the electrochemical corrosion process?

The electrolyte is an electrically conductive solution that must be present for corrosion to occur. It contains positively and negatively charged ions, called cations and anions, which facilitate the transfer of electrons between the electrodes.

Can you explain the reaction between iron and copper in an electrochemical cell during corrosion?

In the example of iron and copper, when the iron electrode is oxidized, it releases two electrons. These electrons travel through a wire to the copper cathode, where they reduce copper ions in the solution, leading to the deposition of copper metal. As a result, the iron electrode shrinks in size while the copper electrode increases in size.

What happens to the electrodes during the corrosion process?

During the corrosion process, the metal at the anode (e.g., iron) loses mass as it oxidizes, while the metal at the cathode (e.g., copper) gains mass as the metal is deposited from the reduction reaction.