key term - Electrolytic Cell

Definition

An electrolytic cell is a type of electrochemical cell that uses electrical energy to drive a non-spontaneous chemical reaction. In this cell, an external power source, such as a battery or power supply, is required to initiate the reaction, allowing the conversion of electrical energy into chemical energy. The processes occurring in electrolytic cells are crucial for understanding concepts like electrolysis and the principles behind various electrochemical reactions.

5 Must Know Facts For Your Next Test

1. In an electrolytic cell, the external voltage must be greater than the cell's voltage to drive the reaction forward.
2. The overall reaction in an electrolytic cell can be thought of as the reverse of a spontaneous reaction that would occur in a galvanic cell.
3. Electrolytic cells are used in various applications, including electroplating, electrorefining, and the production of chemicals like chlorine and hydrogen.
4. Faraday's laws of electrolysis provide a quantitative relationship between the amount of substance produced or consumed at each electrode and the amount of electric charge passed through the cell.
5. Electrolytic cells can also be influenced by factors such as temperature, concentration, and the nature of the electrolyte solution.

Review Questions

• How does the function of an electrolytic cell differ from that of a galvanic cell?
  • An electrolytic cell uses external electrical energy to drive non-spontaneous reactions, while a galvanic cell generates electrical energy from spontaneous chemical reactions. In an electrolytic cell, reactions occur when a voltage is applied, which is needed to overcome the natural tendency of the reactions to not occur. Conversely, in a galvanic cell, the chemical reaction proceeds on its own, producing electricity as a result.
• What are Faraday's laws of electrolysis, and why are they important in understanding electrolytic cells?
  • Faraday's laws of electrolysis quantify the relationship between electric charge and chemical changes occurring at electrodes during electrolysis. The first law states that the amount of substance produced at an electrode is directly proportional to the quantity of electricity that passes through the electrolyte. The second law states that different substances will produce different amounts of products when subjected to the same quantity of electric charge. These laws help explain how efficiently an electrolytic cell can convert electrical energy into chemical energy.
• Evaluate the role of concentration and temperature on the efficiency of an electrolytic cell during electrolysis.
  • Concentration and temperature significantly impact the efficiency of an electrolytic cell. Higher concentrations of reactants can lead to more effective collisions between ions, enhancing reaction rates and product yields. Additionally, increased temperature generally increases kinetic energy, allowing ions to move more freely and react more quickly. However, excessively high temperatures may also lead to undesirable side reactions or evaporation of solvents. Therefore, optimizing both concentration and temperature is crucial for maximizing efficiency during electrolysis.

Related terms

Electrolysis:

The process by which an electrical current is used to drive a chemical reaction, typically involving the decomposition of compounds.

Anode:

The electrode in an electrolytic cell where oxidation occurs and positive ions migrate towards it during electrolysis.

Cathode:

The electrode in an electrolytic cell where reduction takes place, with negative ions migrating towards it during the electrolysis process.