Electrolysis of water is the decomposition of water into oxygen and hydrogen gas due to the passage of an electric current. The reaction has a standard potential of −1.23 V, meaning it ideally requires a potential difference of 1.23 volts to split water.

**Electrolysis of Water**

**Introduction**
Electrolysis of water is a chemical process that involves the decomposition of water molecules into hydrogen gas and oxygen gas using an electric current. It is a highly efficient and powerful technique used to produce these gases for various applications, such as fuel cells, hydrogen production, and industrial processes.

**Principle of Electrolysis**
Electrolysis of water occurs due to the electrolytic conductivity of water. Water is a polar molecule, consisting of two hydrogen atoms and one oxygen atom. When an electric current is passed through water, it dissociates into positively charged hydrogen ions (H+) and negatively charged hydroxide ions (OH-).

**Electrolysis Setup**
To carry out the electrolysis of water, a simple setup is required. It consists of an electrolysis cell containing two electrodes, namely the anode and cathode, which are usually made of inert materials like platinum or graphite. These electrodes are connected to a direct current (DC) power source, such as a battery or a power supply.

**Half-Reactions**
During electrolysis, two half-reactions take place at the electrodes:

1. At the anode: 2H2O(l) → O2(g) + 4H+(aq) + 4e-
Here, water molecules at the anode lose electrons and decompose into oxygen gas, hydrogen ions, and electrons. The electrons flow through the external circuit towards the cathode.

2. At the cathode: 4H+(aq) + 4e- → 2H2(g)
At the cathode, hydrogen ions from the solution gain electrons and are reduced to form hydrogen gas.

**Electrolysis Process**
When the electric current is applied, hydrogen ions (H+) are attracted towards the cathode (negative electrode), while hydroxide ions (OH-) are attracted towards the anode (positive electrode). At the anode, water molecules lose electrons and produce oxygen gas, while at the cathode, hydrogen ions gain electrons and generate hydrogen gas.

**Overall Reaction**
The overall reaction for the electrolysis of water can be summarized as:
2H2O(l) → 2H2(g) + O2(g)

**Gas Collection and Purity**
The produced hydrogen and oxygen gases can be collected separately by using gas collection tubes or containers. To ensure purity, it is crucial to use high-quality electrodes and pure water without impurities or dissolved salts that could interfere with the electrolysis process.

**Conclusion**
Electrolysis of water is a fundamental process that allows the decomposition of water into its constituent gases, hydrogen and oxygen, through the application of an electric current. This technique has numerous applications in various industries and research fields, particularly in the production of hydrogen gas, which is considered a clean and efficient energy carrier.