What is Electrolytic and Electrochemical Cell: Introduction
To differentiate between electrolytic and electrochemical cell: Electrolytic and electrochemical cells are essential components of electrochemistry, a branch of chemistry that focuses on chemical reactions involving electricity. Electrolytic cells use an external power source to drive non-spontaneous chemical reactions. They consist of two electrodes (anode and cathode) submerged in an electrolyte solution. By applying an electric current, ions migrate to the electrodes, where they undergo oxidation at the anode and reduction at the cathode. On the other hand, electrochemical cells, such as galvanic or voltaic cells, generate electrical energy from spontaneous chemical reactions. They convert chemical energy into electrical energy through redox reactions, producing a flow of electrons from the anode to the cathode. Read further for more.
What is Electrolytic Cell
An electrolytic cell is a device that utilizes an external source of electrical energy to facilitate a non-spontaneous chemical reaction. It consists of two electrodes—an anode and a cathode—immersed in an electrolyte solution. When an electric current is applied through the cell, cations migrate towards the cathode, where they undergo reduction, while anions migrate toward the anode, where they undergo oxidation. This process allows for the separation and transformation of ions within the electrolyte. Electrolytic cells are employed in various applications, including electroplating, electrolysis of water, and industrial-scale production of chemicals, and they play a crucial role in electrolysis processes. The features of electrolytic cells are:
External power source: An electrolytic cell requires an external power source, such as a battery or power supply, to drive the non-spontaneous reaction.
Electrodes: It consists of two electrodes—an anode (positive electrode) and a cathode (negative electrode)—that are made of conductive materials, typically metal or graphite.
Electrolyte solution: The electrodes are immersed in an electrolyte solution, which contains ions that participate in the electrochemical reactions.
Non-spontaneous reactions: Electrolytic cells facilitate non-spontaneous chemical reactions, meaning reactions that do not occur naturally without external energy input.
Electrolysis: The process of electrolysis occurs in an electrolytic cell, where the external power source drives the migration and transformation of ions at the electrodes.
Reduction and oxidation: Reduction occurs at the cathode, where positively charged ions gain electrons, while oxidation occurs at the anode, where negatively charged ions lose electrons.
What is Electrochemical Cell
An electrochemical cell is a device that converts chemical energy into electrical energy through a spontaneous redox (reduction-oxidation) reaction. It consists of two electrodes—an anode and a cathode—submerged in an electrolyte solution. The anode undergoes oxidation, releasing electrons, while the cathode undergoes reduction, accepting those electrons. The movement of electrons through an external circuit generates an electric current. Electrochemical cells are classified into galvanic (voltaic) cells, which produce electrical energy, and electrolytic cells, which require an external power source. These cells find applications in batteries, fuel cells, corrosion protection, and various electrochemical processes, playing a pivotal role in powering electronic devices and industrial processes. The features of electrochemical cells are:
Spontaneous redox reactions: Electrochemical cells involve spontaneous oxidation-reduction (redox) reactions, where one electrode undergoes oxidation (loses electrons) and the other undergoes reduction (gains electrons).
Electrodes: The cell has two electrodes—an anode and a cathode. The anode is where oxidation occurs, while the cathode is where reduction occurs.
Electrolyte: An electrolyte solution is present, which contains ions that facilitate the movement of charge within the cell.
Electron flow: Electrons flow from the anode to the cathode through an external circuit, generating an electric current.
Chemical energy conversion: The cell converts chemical energy into electrical energy through the redox reaction.
Voltaic (galvanic) and electrolytic cells: Electrochemical cells can be classified into voltaic cells, which spontaneously generate electrical energy, and electrolytic cells, which require an external power source.
Differentiate Between Electrolytic and Electrochemical Cell
While both types of cells have similarities, the key distinction lies in the purpose and energy conversion process. Electrolytic cells require an external power source to drive non-spontaneous reactions, while electrochemical cells generate electrical energy from spontaneous redox reactions.
Summary
An electrolytic cell is a setup that utilizes an external power source to drive a non-spontaneous chemical reaction. It consists of two electrodes—an anode and a cathode—immersed in an electrolyte solution. When an electric current is passed through the cell, ions migrate towards the electrodes, where they undergo oxidation at the anode and reduction at the cathode.
In contrast, an electrochemical cell, such as a galvanic or voltaic cell, generates electrical energy from a spontaneous chemical reaction. It converts chemical energy into electrical energy through a redox reaction, producing a flow of electrons from the anode to the cathode. This flow of electrons can be harnessed for practical applications.
FAQs on Difference Between Electrolytic and Electrochemical Cell for JEE Main 2024
1. How does an electrolytic cell work?
An electrolytic cell operates by using an external power source, such as a battery or power supply, to drive a non-spontaneous chemical reaction. The cell consists of two electrodes—an anode and a cathode—immersed in an electrolyte solution. When the external power source is connected, it creates an electric field within the cell. This electric field causes positive ions (cations) to move towards the cathode, where reduction occurs, and negative ions (anions) to move towards the anode, where oxidation occurs. The transfer of electrons and ions at the electrodes leads to chemical transformations and the desired non-spontaneous reaction, which can include processes like electrolysis, electroplating, and industrial applications.
2. What is the purpose of an electrochemical cell?
The purpose of an electrochemical cell is to convert chemical energy into electrical energy through a spontaneous redox (reduction-oxidation) reaction. By harnessing the inherent ability of certain chemical reactions to transfer electrons, an electrochemical cell generates an electric current. Electrochemical cells, such as batteries and fuel cells, play a vital role in energy storage and conversion, enabling portable power sources, sustainable energy solutions, and advancements in fields ranging from electronics to transportation and beyond.
3. How is an external power source used in an electrolytic cell?
In an electrolytic cell, an external power source, such as a battery or power supply, is connected to drive a non-spontaneous chemical reaction. The power source provides an electric potential difference between the two electrodes—anode and cathode—of the cell. This external voltage creates an electric field within the cell, causing the movement of charged particles. Positive ions (cations) are attracted to the cathode, while negative ions (anions) migrate towards the anode. The electric current supplied by the external power source facilitates the transfer of electrons and the desired chemical transformations at the electrodes, enabling non-spontaneous reactions such as electrolysis, electroplating, and other processes.
4. How are ions involved in an electrochemical cell?
Ions play a crucial role in an electrochemical cell. They facilitate the flow of electric charge and enable the movement of species within the cell. In the electrolyte solution, positive ions (cations) migrate towards the cathode, while negative ions (anions) move towards the anode. This ion movement maintains charge balance within the cell and completes the circuit for electron transfer. The migration of ions helps sustain the redox reactions at the electrodes and ensures the continuous flow of current, enabling the generation of electrical energy or driving electrochemical processes.
5. Can an electrochemical cell be used for electrolysis?
Yes, an electrochemical cell can be used for electrolysis. Electrolysis is a process that uses an electric current to drive a non-spontaneous chemical reaction. In an electrochemical cell, an external power source is connected to provide the necessary electric current. The electric current induces redox reactions at the electrodes, facilitating the decomposition of compounds into their constituent ions or elements. This process is commonly employed in various industrial applications, such as the production of metals, extraction of reactive elements, electrolytic refining, and electrolysis-based technologies for water splitting to generate hydrogen gas.
