Understanding the Process of Electrolysis of Water

Electrolysis of water is the chemical reaction that occurs when an electric current is passed through a solution of water, resulting in the decomposition of water molecules into their constituent elements: hydrogen and oxygen.

The reaction takes place in an electrolysis cell, which consists of two electrodes (an anode and a cathode) and a solution of water (which acts as an electrolyte). The anode is typically made of an inert material such as platinum or carbon, while the cathode can be made of a variety of metals.

When an electric current is passed through the water, the anode becomes positively charged and the cathode becomes negatively charged. This causes the water molecules to dissociate into their constituent ions: hydrogen ions (H+) are attracted to the cathode, while hydroxide ions (OH-) are attracted to the anode.

At the cathode, hydrogen ions gain electrons from the electric current and are reduced to form hydrogen gas (H2):

2H+ + 2e- → H2

At the anode, hydroxide ions lose electrons to the electric current and are oxidized to form oxygen gas (O2):

4OH- → 2H2O + O2 + 4e-

Overall, the balanced equation for the electrolysis of water is:

2H2O → 2H2 + O2

The process of electrolysis can be used to generate hydrogen and oxygen gas for a variety of applications, including fuel cells and chemical synthesis. It can also be used to purify water and remove impurities, as the electric current can break down many types of contaminants into their constituent ions.