Editing Electrolyte (section)

== Electrochemistry ==
{{Main|Electrolysis}}
When [[electrode]]s are placed in an electrolyte and a [[voltage]] is applied, the electrolyte will conduct electricity. Lone [[electron]]s normally cannot pass through the electrolyte; instead, a chemical reaction occurs at the [[cathode]], providing electrons to the electrolyte.   Another reaction occurs at the [[anode]], consuming electrons from the electrolyte. As a result, a negative charge cloud develops in the electrolyte around the cathode, and a positive charge develops around the anode. The ions in the electrolyte neutralize these charges, enabling the electrons to keep flowing and the reactions to continue.{{cn|date=November 2021}}
[[File:Chloralkali membrane.svg|600px|thumb|right|[[Electrolytic cell]] producing [[chlorine]] (Cl<sub>2</sub>) and [[sodium hydroxide]] (NaOH) from a solution of common salt]]
For example, in a solution of ordinary table salt (sodium chloride, NaCl) in water, the cathode reaction will be

: 2 H<sub>2</sub>O + 2e<sup>−</sup> → 2 OH<sup>−</sup> + H<sub>2</sub>

and [[hydrogen]] gas will bubble up; the anode reaction is

: 2 NaCl → 2 Na<sup>+</sup> + Cl<sub>2</sub> + 2e<sup>−</sup>

and [[chlorine]] gas will be liberated into solution where it reacts with the sodium and hydroxyl ions to produce [[sodium hypochlorite]] - household [[bleach]]. The positively charged sodium ions Na<sup>+</sup> will react toward the cathode, neutralizing the negative charge of OH<sup>−</sup> there, and the negatively charged hydroxide ions OH<sup>−</sup> will react toward the anode, neutralizing the positive charge of Na<sup>+</sup> there. Without the ions from the electrolyte, the charges around the electrode would slow down continued electron flow; [[diffusion]] of H<sup>+</sup> and OH<sup>−</sup> through water to the other electrode takes longer than movement of the much more prevalent salt ions.
Electrolytes dissociate in water because water molecules are dipoles and the dipoles orient in an energetically favorable manner to [[Solvation|solvate]] the ions.{{cn|date=April 2025}}

In other systems, the electrode reactions can involve the metals of the electrodes as well as the ions of the electrolyte.{{cn|date=April 2025}}

Electrolytic conductors are used in electronic devices where the chemical reaction at a metal-electrolyte interface yields useful effects.
* In [[battery (electricity)|batteries]], two materials with different electron affinities are used as electrodes; electrons flow from one electrode to the other outside of the battery, while inside the battery the circuit is closed by the electrolyte's ions. Here, the electrode reactions convert chemical energy to electrical energy.<ref name="Wladyslaw Wieczorek-2011">{{cite journal|author1=Kamil Perzyna |author2=Regina Borkowska |author3=Jaroslaw Syzdek |author4=Aldona Zalewska |author5=Wladyslaw Wieczorek |title=The effect of additive of Lewis acid type on lithium–gel electrolyte characteristics|journal=Electrochimica Acta| volume=57|pages=58–65|year=2011|doi=10.1016/j.electacta.2011.06.014}}</ref>
* In some [[fuel cell]]s, a solid electrolyte or [[proton conductor]] connects the plates electrically while keeping the hydrogen and oxygen fuel gases separated.<ref name="Jan Fransaer-2015"/>
* In [[electroplating]] tanks, the electrolyte simultaneously deposits metal onto the object to be plated, and electrically connects that object in the circuit.{{cn|date=April 2025}}
* In operation-hours gauges, two thin columns of [[mercury (element)|mercury]] are separated by a small electrolyte-filled gap, and, as charge is passed through the device, the metal dissolves on one side and plates out on the other, causing the visible gap to slowly move along.{{cn|date=April 2025}}
* In [[electrolytic capacitor]]s the chemical effect is used to produce an extremely thin [[dielectric]] or [[Electrical insulation|insulating]] coating, while the electrolyte layer behaves as one capacitor plate.{{cn|date=April 2025}}
* In some [[hygrometer]]s the humidity of air is sensed by measuring the conductivity of a nearly dry electrolyte.{{cn|date=April 2025}}
* Hot, softened glass is an electrolytic conductor, and some glass manufacturers keep the glass molten by passing a large current through it.{{cn|date=April 2025}}