Short Answer

An electrolytic cell is an electrochemical cell that uses electrical energy to drive a non-spontaneous chemical reaction. In this cell, an external power source forces electrons to move from one electrode to another, allowing decomposition or chemical changes to occur. Electrolysis of water and metal extraction processes use electrolytic cells.

In an electrolytic cell, oxidation happens at the anode and reduction occurs at the cathode, just like in other electrochemical systems. However, the major difference is that an electrolytic cell requires electricity from outside, making it useful for electroplating, purification of metals, and production of chemicals.

Detailed Explanation :

Electrolytic Cell

An electrolytic cell is an electrochemical device in which electrical energy is supplied from an external source to bring about a chemical reaction that does not occur on its own. Unlike a galvanic cell, which produces electricity from spontaneous reactions, an electrolytic cell consumes electricity to force a reaction to take place. This process is known as electrolysis.

Electrolytic cells are widely used in industrial processes such as metal extraction, electroplating, and the manufacture of chemicals like chlorine, hydrogen, and sodium hydroxide. Understanding how an electrolytic cell works helps us explain many technological and industrial applications.

1. Structure of an Electrolytic Cell

An electrolytic cell consists of several key parts:

1. a) Electrolyte

A molten ionic compound or aqueous solution that allows ions to move.

1. b) Electrodes

• Anode (Positive Electrode) – oxidation occurs here.
• Cathode (Negative Electrode) – reduction occurs here.

1. c) Power Source

A battery or DC power supply pushes electrons into the cathode and pulls electrons from the anode.

1. d) Container

Holds the electrolyte and electrodes.

Electrodes may be active (take part in the reaction) or inert (do not react, like carbon or platinum rods).

2. Working of an Electrolytic Cell
3. a) Flow of Electrons

The external power source forces electrons:

• Out of the anode, making oxidation occur
• Into the cathode, making reduction occur

1. b) Oxidation at the Anode

Anions lose electrons.
Example: 2Cl⁻ → Cl₂ + 2e⁻

1. c) Reduction at the Cathode

Cations gain electrons.
Example: Na⁺ + e⁻ → Na

1. d) Ion Movement

• Positive ions (cations) move toward the cathode
• Negative ions (anions) move toward the anode

These movements complete the electrical circuit and allow continuous reaction.

3. Difference Between Galvanic and Electrolytic Cells

Feature	Galvanic Cell	Electrolytic Cell
Reaction	Spontaneous	Non-spontaneous (requires power)
Energy	Produces electrical energy	Consumes electrical energy
Anode	Negative	Positive
Cathode	Positive	Negative
Purpose	Power generation	Electrolysis, metal extraction, plating

Although the charges of electrodes differ, oxidation always occurs at the anode and reduction at the cathode.

4. Types of Electrolytic Processes
5. a) Molten Electrolysis

Used when ionic compounds cannot dissolve in water.
Example: Electrolysis of molten NaCl to obtain sodium and chlorine.

1. b) Aqueous Electrolysis

Water and dissolved ions participate in the reaction.
Example: Electrolysis of water to produce hydrogen and oxygen.

5. Applications of Electrolytic Cells

Electrolytic cells are extremely important in industries and daily life.

1. a) Metal Extraction

Metals like aluminium, magnesium, and sodium are extracted from molten salts using electrolytic reduction.

1. b) Electroplating

Used to coat objects with a thin metal layer such as gold, silver, chromium, or nickel.

1. c) Metal Purification

Copper and other metals are purified by electrolytic refining.

1. d) Manufacturing Chemicals

Electrolytic cells produce:

• Chlorine gas
• Sodium hydroxide
• Hydrogen gas
• Oxygen gas

1. e) Electrolysis of Water

Used to produce hydrogen fuel for energy systems.

6. Importance of Electrolytic Cells

Electrolytic cells are useful because they:

• Allow extraction of reactive metals that cannot be obtained by simple chemical reduction
• Help produce chemicals essential to industry
• Enable recycling and purification of metals
• Provide decorative and protective coatings through electroplating
• Support clean energy technologies like hydrogen production

These applications show how electrolytic cells contribute to modern technology and industrial development.

7. Factors Affecting Electrolytic Cell Reactions

Several factors determine the products of electrolysis:

1. a) Nature of Electrolyte

Whether it is molten or aqueous affects which ions are available.

1. b) Electrode Material

Active electrodes may participate in the reaction.

1. c) Voltage Applied

Higher voltage can change which species get reduced or oxidized.

1. d) Ion Concentration

Higher ion concentration increases reaction efficiency.

Conclusion

An electrolytic cell is an electrochemical system that uses electrical energy to drive non-spontaneous chemical reactions. Oxidation occurs at the anode, and reduction occurs at the cathode. These cells are essential in electroplating, extraction and purification of metals, and chemical manufacturing. They also support clean energy systems like hydrogen production. Understanding electrolytic cells helps explain how industries use electricity to perform chemical transformations.