What is Electrolysis?
Electrolysis is the process of passing an electric current through a substance to cause a chemical change. A chemical change occurs when a substance loses or gains an electron (oxidation or reduction). The procedure is carried out in an electrolytic cell, which is a device comprised of positive and negative electrodes held apart and immersed in a solution containing positively and negatively charged ions. The substance to be transformed could be the electrode, the solution, or it could be dissolved in the solution. Electric current (i.e., electrons) enters the system through the negatively charged electrode (cathode); solution components travel to this electrode, combine with the electrons, and are transformed (reduced). The end result could be neutral elements or new molecules.
Components of the solution also travel to the opposite electrode (anode), where they give up their electrons and are transformed (oxidized) to neutral elements or new molecules. If the substance to be transformed is an electrode, the reaction is frequently one in which the electrode dissolves by releasing electrons.
What is Electrode?
An electrode is an electrical conductor that makes contact with a circuit’s non-metallic circuit parts, such as an electrolyte, semiconductor, or vacuum. This is also known as an anode or cathode in an electrochemical cell. The anode is an electrode where electrons leave the cell and oxidation occurs. Electrons enter the cell through the cathode, where they undergo a reduction process.
Electrodes are classified into two categories. They are
- Cathode
- Anode
What is Cathode?
It is an electrode from which a polarised electrical device’s current flows. The mnemonic Cathode Current Departs can help you remember this. A conventional current indicates the direction of positive charge movement. Electrons are electrically charged negatively. As a result, the movement of electrons is diametrically opposed to the flow of current.
How does cathode work?
A cathode is essentially there to receive electrons from the anode. Both the anode and cathode are immersed in an electrolyte solution, and electricity flows from the negative to positive parts of your battery via the conductor. In a nutshell, this is how a battery produces electricity.
What are the materials good for cathode?
Copper oxide, Lithium oxide, and Graphic oxide.
Types of Cathodes
Directly heated cathode: In this case, the filament serves as the cathode and directly emits electrons.
Indirectly heated cathode: The filament is not the cathode in this type of cathode; rather, it heats the cathode, which subsequently produces electrons.
What is Anode?
An Anode is a highly polarised electrode through which electric current flows into a device. Typically, the direction of the current is always the inverse of the flow of electrons.
As an example, electrons travel from a positive charge, or anode, into an electrical circuit. ACID, which stands for “anode: current into the device,” is a popular mnemonic for defining an anode.
How does an Anode work?
An anode is a metal that oxidizes, such as zinc or lithium, and thus loses electrons. It floats in an electrolyte solvent and slowly deteriorates as electrons flow along a conductor to the cathode.
The conductor (whether a metal wire or a tube) is how we access the electricity produced by the anode and, ultimately, how a battery powers our devices. The battery will die once the anode has completely eroded (or lost charge).
What are the materials good for Anode?
Zinc, Lithium, Graphite, or Platinum.
Types of Anode
Anodes are classified into several types:
- Galvanic cell anode - A negatively charged electrode from which electrons travel out through the circuit’s outer portion.
- Electrolytic anode - The anode is the site of oxidation in electrochemistry and contains the positive charge in contact with the electrolytic cell.
- Anode diode - The P-doped portion of a semiconductor diode corresponds to the anode and brings holes into the joint area. The anode supply holes connect with electrons from the N-doped area, resulting in a depleted region.
- Vacuum tube - In vacuum devices such as cathode ray tubes, the anode is always positively charged and collects the electrons released by the cathode through electric attraction.
Representation of Cathode and Anode in batteries
Cells are made up of three essential components.
The anode is the negative or reducing electrode that releases electrons to the external circuit and oxidizes during an electrochemical reaction.
The Cathode is the positive or oxidizing electrode that takes electrons from the external circuit and reduces them during the electrochemical reaction.
The electrolyte is the medium that allows ions to move between the cathode and anode of a cell. Electrolytes are frequently conceived of as liquids, such as water or other solvents, containing dissolved salts, acids, or alkalis necessary for ionic conduction. However, many batteries, including standard (AA/AAA/D) batteries, contain solid electrolytes that act as ionic conductors at room temperature.
Anode Vs Cathode
| S. No | Anode | Cathode |
|---|---|---|
| 01 | Anode is the negative charge electrode | Cathode is the positive charge electrode |
| 02 | Anode attracts negative charge (repels positive charges) | Cathode attracts positive charge (repels negative charges) |
| 03 | Anode referred as the source of positive charge | Cathode referred as the source of negative charge |
| 04 | Where an oxidation process occurs | Reduction process occurs |
| 05 | In galvanic cells, an anode can become a cathode. | In galvanic cells, a cathode can become an anode. |
| 06 | It acts as an electron donor. | It acts as an electron acceptor. |
Application of Anode and Cathode in industries
Applications of electrolysis are
- Extraction of metals (extraction of Aluminium, Zinc, and Sodium)
- Purification of metals (Purification of copper)
- Electroplating of metals
Some Useful Questions
1. Does Oxidation occur on Cathode and Anode?
No, the oxidation process occurs only in anode where the reduction process occurs in the cathode.
2. What are the materials used for making Cathode and Anode?
Materials to make anode:- Zinc, Lithium, Graphite, or Platinum.
Materials to make cathode:- Copper oxide, Lithium oxide, and Graphic oxide.
3. Is LED Cathode positive or negative?
LEDs are typically identified in some way by their cathode. The cathode should be connected to the driving voltage source’s floor or negative side, while the anode should be connected to the positive side.
4. Are cations positive or negative?
A cation is a positively charged ion or atom that has lost one of its electrons.