Introduction to Electrolysis

Electrolysis is a chemical process that uses an electric current to drive a reaction. It is commonly used to split a molecule into its component elements or to deposit a metal onto a surface.

Image from JEE 2022

How Electrolysis Works

Electrolysis works by passing an electric current through a solution called an electrolyte. The electrolyte is typically a liquid or gel-like substance that contains ions, which are atoms or molecules that have gained or lost electrons. When an electric current is applied to the electrolyte, the ions are attracted to the electrodes (the positive and negative terminals of the electric circuit). At the electrodes, the ions undergo a chemical reaction, resulting in the formation of new compounds or the release of gases.

Components of an Electrolysis System

An electrolysis system typically consists of the following components:

• Electrolyte: The solution that contains the ions to be reacted.
• Anode: The positive electrode, where oxidation occurs.
• Cathode: The negative electrode, where reduction occurs.
• Power source: The device that provides the electric current.

What Electrolysis Does

Electrolysis has a number of practical applications, including:

• Purifying metals: Electrolysis can be used to remove impurities from metals.
• Producing chemicals: Electrolysis can be used to produce chemicals such as chlorine and sodium hydroxide.
• Splitting water: Electrolysis can be used to split water into hydrogen and oxygen.
• Plating metals: Electrolysis can be used to deposit a thin layer of metal onto a surface.

Simple Example of Electrolysis

A simple example of electrolysis is the production of hydrogen and oxygen from water. This can be done using a device called an electrolytic cell, which consists of two electrodes (an anode and a cathode) immersed in a solution of water. When an electric current is applied to the electrodes, the water molecules are split into hydrogen and oxygen gases.

H2O -> 2H+ + O2-
at anode: 2H+ -> H2
at cathode: O2- -> O2

This is a basic overview of electrolysis. The process has many real-world applications, and is an important part of many industrial and scientific processes.