How Do Galvanic Cells Work

A galvanic cell is a good example of how energy may be harnessed by employing basic chemical reactions between a few materials. It is fascinating to learn how to set up and use a galvanic cell to generate energy.

In a nutshell, a galvanic cell undergoes both reduction and oxidation reactions at the same time. Chemical energy is converted into electrical energy, which can be used for any commercial purpose, using these reactions.

In a redox reaction, transfer of electrons generate electricity, which is channelled through a galvanic cell. A circuit, such as a television or a light bulb, can receive electrical energy or current.

The anode (-) is the electrode of the oxidation half-cell, whereas the cathode (+) is the electrode of the reduction half-cell. To remember that reduction occurs at the cathode and oxidation occurs at the anode, utilise the mnemonic “The Red Cat Ate an Ox.”

A voltaic cell, sometimes known as a Daniel cell, is a type of galvanic cell.

Working of Galvanic Cells

The operation of a galvanic cell is relatively straightforward. It entails a chemical reaction that produces electric energy as a byproduct. A galvanic cell uses the energy transfer between electrons to transform chemical energy into electric energy during a redox reaction.

The ability to split the flow of electrons in the process of oxidation and reduction, generating a half-reaction, and linking each with a wire so that a channel for the flow of electrons through such wire can be produced, is used in a galvanic cell. The flow of electrons is referred to as a current. A current of this type can be made to flow via a wire to complete a circuit and obtain output in any device, such as a television or a watch.

Any two metals can be used to make a galvanic cell. If these two metals come into contact with each other, they can create the anode and cathode. This combination permits more anodic metals to experience galvanic corrosion. To allow this corrosion to occur, a connecting circuit will be required.

Manufacturing a Galvanic Cell

To make a galvanic cell, you’ll need to follow the steps below. Two electrodes would be great for the cell. Cathode is present on one of these electrodes, while the anode, a negatively charged electrode, will be the other.

The galvanic cell’s two fundamental components will be these two electrodes. The reduction half-reaction should happen at the cathode, whereas the oxidation half-reaction should happen at the anode. Any two metals can be utilised to induce the chemical reaction, as previously stated.

An Example to Help You Understand the Galvanic Cell

Let’s look at a situation where zinc and copper are the two metals involved in a chemical reaction. Zinc loses two electrons due to the chemical process. Copper absorbs this and turns it into an elemental copper. Because these two metals will be placed in separate containers and connected by a conducting wire, an electric current will form, transferring all electrons from one metal to the other.

The two metals must be immersed in a salt solution at the same time, such as Zinc sulphate and Copper sulphate in this case. The two solutions are not directly blended in this example but can be linked using a bridge or a medium. This medium will be in charge of transferring ions while also ensuring that the two solutions do not combine.

This type of bridge aids in the completion of the circuit for carrying the electric charge, as well as ensuring that the solutions in the metal containers remain neutral and do not mix. It doesn’t matter which salt bridge is used in the chemical reaction as long as it doesn’t interfere with the redox reaction, which is where oxidation and reduction take place.

Important Terms and phrases

The following are some of the key phrases that are used in galvanic cells:

• The two metals that operate as the cathode and anode are referred to as phase boundaries.
• The connecting bridge or medium that allows a redox reaction to take place is called a salt bridge.
• The chemical processes that allow an electric current to generate and flow through a galvanic cell are oxidation and reduction.

Types of Galvanic Cells

A galvanic cell might be one of three types.

• Concentration Cell

A concentration cell is a non-rechargeable primary cell that consists of two galvanic half cells that contain the same chemical species but different concentrations. Example, A cell having two hydrogen electrodes which are at distinct gaseous pressure immersed in the same solution.

• Electrolytic Cell

An electrolytic cell is made up of two electrodes submerged in an electrolyte tank. The electrolyte is usually made up of two electrolyte solutions that exchange ions via a salt bridge or a porous septum. Example ,Rechargeable battery is an example of an electrolytic cell.

• Electrochemical Cell

Electrochemical cells, also known as half cells, are made up of two half-elements.   Example ,a standard 1.5 volt cell.

Conclusion

An electrolytic cell consumes electrical energy from an external source to force a reaction to occur, whereas a galvanic (voltaic) cell generates electricity using the energy produced during a spontaneous redox reaction. The study of the link between electricity and chemical reactions is known as electrochemistry. 

During an electrochemical process, the oxidation-reduction reaction is split into two half-reactions, one representing the oxidation process and the other representing the reduction process. The total chemical reaction is equal to the sum of the half-reactions. When electrons reduced by the reductant are equal to the electrons gained by oxidant, the entire redox reaction is balanced. The movement of electrons from the reductant to the oxidant generates an electric current.