Electrochemical processes involve the movement of electric current in redox reactions, playing a role in natural phenomena and modern technology. The nervous system relies on electrochemical processes for communication, while electric fish use them to produce electric fields. Batteries use different chemical reactions to store and release electricity, and electrolysis triggers chemical reactions in substances containing free ions.
An electrochemical process is a chemical reaction that causes or is caused by the movement of electric current. These processes are a type of redox reaction in which one atom or molecule loses an electron to another atom or molecule. In electrochemical reactions, the atoms or molecules in the reaction are relatively far apart from each other compared to other reactions, forcing the electrons being transferred to travel a greater distance and thus produce an electric current. Many natural phenomena are based on electrochemical processes, such as the corrosion of metals, the ability of some marine creatures to generate electric fields, and the functioning of the nervous systems of humans and other animals. They also play an important role in modern technology, especially the storage of electrical energy in batteries, and the electrochemical process called electrolysis is important in modern industry.
The activities of the nervous system, from simple instinctive reactions and behaviors found even in primitive animals to the complex learning and reasoning abilities of humans, depend on electrochemical processes. Neurons use electrochemical processes to transmit information throughout the nervous system, enabling the nervous system to communicate with itself and with the rest of the body. To send a signal, chemical processes in the neuron generate an electrical impulse that is sent through an elongated structure called an axon until it reaches the synapse, the point of contact between the neuron and neighboring cells. At the synapse, the electricity causes the release of chemicals called neurotransmitters, which cross the synapse to the signaled cell. The neurotransmitters then chemically bind with structures called receptors on the target cell, triggering further biochemical processes within it.
The ability of fish such as electric eels, stargazers and torpedoes to produce electric fields is the result of an electrochemical process. Electric fish possess specialized cells called electrocytes. Carrier proteins bind to positive potassium and sodium ions in the cell and carry them away, building an electrical charge in the cell. When this electricity is needed, a part of the nervous system called the nucleus of the medulla sends an electrical impulse to other nerve cells, which triggers the release of the neurotransmitter acetylcholine. The neurotransmitter binds to the electrocyte’s acetylcholine receptors, which triggers the release of the electrocyte’s charge.
Electric batteries use electrochemical processes to store and release electricity. Chemical reactions within the electrical cells that make up the battery create a difference in charge between the two halves of each cell, producing an electric current. Rechargeable batteries produce electricity in reversible chemical reactions and therefore can be returned to their original chemical configuration if electricity is applied from an external source. The reactions in non-rechargeable batteries do not have this quality, although they usually produce more electrical energy than a rechargeable battery can supply on a single charge.
Different chemical reactions are used in batteries. Nickel-cadmium batteries, commonly used in lights and appliances, are based on separate reactions of cadmium and nickel with an alkali, usually a solution of potassium hydroxide (KOH) and water. Nickel-metal hydride batteries are similar, but replace cadmium with an intermetallic compound made from manganese, aluminum, or cobalt mixed with rare earth metals such as praseodymium, lanthanum, and cerium. Lithium batteries can use a variety of reactions involving lithium compounds, with the most common type using manganese dioxide (MnO2) and a solution of lithium perchlorate (LiClO4), dimethoxyethane (C4H10O2), and propylene carbonate (C4H6O3 ).
Electrolysis is an electrochemical process in which electric current is used to trigger chemical reactions in a substance containing free ions, called an electrolyte. The electrolyte is melted or dissolved in a solvent and two electrodes, called anode and cathode, are immersed in it. When an electrical potential is applied between the electrodes, electricity begins to flow between them and each electrode begins to attract ions with the opposite of its charge. Ions gain or lose electrons at the electrodes, causing molecules near the anode to oxidize and those near the cathode to reduce. Electrolysis is used in many areas of industrial processes, including metallurgy, the production of chemicals such as potassium chlorate and trifluoroacetic acid (KClO3) (C2HF3O2), and the extraction of highly reactive elements not found in their elemental form in nature, such as sodium and magnesium.
Protect your devices with Threat Protection by NordVPN
