Electrodes - Definition, Factors, Types, Uses, FAQs

What is Electrode and Examples of Electrodes?

Electrode Definition: Electrode meaning is a point where current enters or leaves the electrolyte or circuit is referred to as an electrode. The cathode is where the current departs the electrode, while the anode is where the current enters the electrode. Electrodes are the basic building blocks of electrochemical cells. A good conductor of electricity is required for an electrode. Although there are inert electrodes that do not participate in the process. Gold, platinum, carbon, graphite, metal, and other materials can be used as electrodes. In the cells, the electrode provides a surface for oxidation-reduction reactions.

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Types of electrodes

There are two types of electrodes: active electrodes and inert electrodes. Active electrode materials are those that participate in the chemical process in the cell and can dissolve in the electrolyte. Copper electrodes, silver electrodes, zinc electrodes, copper electrodes, and so on are examples of reactive electrodes. These are mostly employed in potentiometric measurements.

Active Electrode

In electrochemical cells, the active electrode is a metal electrode. It takes part in the electrolyte's processes in order to transmit the power. It is possible to oxidize or decrease the active electrode. Electroplating is the most common application for active electrodes. Electroplating is the process of applying one metal to another metal using an electrochemical cell. A spoon, for example, can be silver-plated by employing a silver anode and the spoon as the cathode, with silver nitrate as the electrolyte. The active electrode gets its name from the fact that it actively participates in the chemical reaction that takes place in the system. It actively exchanges ions with an electrolytic solution as a result.

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Inert Electrode

A metal that does not participate in or interfere with any chemical reaction is known as an inert electrode. However, rather of exchanging ions with the solution, it is still employed to conduct electricity via transferring electrons. As a result, it functions as an electron. As an inert electrode, platinum is employed. However, graphite is commonly used because to its low cost. However, graphite is commonly used because to its low cost. In the process of conducting electricity, an inert electrode can provide or withdraw electrons. Electrolysis, the process of separating an ionic compound into its constituent elements, always uses inert electrodes. When sodium chloride solution is electrolyzed, sodium and chlorine are produced individually.

Cathode and Anode in Electrochemical cells

An electrode in an electrochemical cell is referred to as either a cathode or an anode. The anode is the electrode where electrons leave the cell and oxidation takes place, whereas the cathode is the electrode where electrons enter the cell and reduction takes place. Depending on the direction of current through the cell, any of the two electrodes can become an anode or a cathode. Bipolar electrodes are those that can operate as anode in one cell and cathode in another.

Primary cells are electrochemical cells in which irreversible reactions occur, which is why the cathode and anode identities are fixed in these cells. The anode in these cells will always be negative, implying that oxidation will always occur. While the cathode will always be positive, or at this point, there will always be a reduction. Galvanic cell is an example of a primary cell. Secondary cells, also known as electrolytic cells, are rechargeable, which means they undergo reversible chemical reactions. The anode is always positive in these cells, while the cathode is constantly negative.

Factors Affecting Products of Electrolysis

1. The electrolysis products are determined by the material being electrolyzed. In other words, the electrolysis process is governed by the type of the electrolyte. For a strong electrolyte, the procedure is quick, but for a weak electrolyte, an extra potential, also known as excess potential, is necessary. The value of this excess potential affects the electrolysis products as well.

2. The type of the electrodes has an impact on the electrolysis products. In other words, an inert electrode (such as gold or platinum) does not participate in the process, whereas an active electrode does.

3. The electrolytic products are affected by various oxidising and reducing species present in the electrolytic cell.

4. The electrolytic cell's products are determined by the standard electrode potentials of the various oxidising and reducing species present.

5. In the case of several reactions, the electrolysis product is determined by the standard electrode potential of the individual reactions. For instance, electrolysis of a sodium chloride aqueous solution. The reduction process with the highest standard electrode potential takes place at the cathode, out of the many reduction reactions taking place. Similarly, the oxidation process with the lowest standard electrode potential occurs at the anode, out of the many oxidation reactions.

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Uses of electrodes

In a cell, electrodes are utilised to make contact between nonmetal circuit components.

• Conductivity is measured using electrodes.

• These are utilised in car fuel cells.

• Medical devices such as EEG, ECG, ECT, and defibrillators employ them.

• These are employed in biomedical research for electrophysiological procedures.

• These are employed in the electric chair execution.

• Electroplating is done with them.

• Arc welding is done with them.

• These are utilised as a grounding device.

• Electrochemistry makes use of them.

• These are used to determine the chemical composition of substances.

• These are utilised in the assembly of membrane electrodes.

• Electroshock weapons make advantage of them

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