Electrolytic Cell

An electrolytic cell is a device that utilizes electrical energy to decompose some chemical compounds by a process known as Electrolysis. The electrolytic cell is nothing but a special kind of electrochemical cell. Ex: When water undergoes electrolysis, it breaks into hydrogen and oxygen. Here some additional energy is required to overcome the threshold energy barrier.

Voltaic cells are driven by a spontaneous chemical reaction that produces an electric current through an external circuit. These cells are essential because they are the basis for the batteries that fuel modern society. However, they are not the only kind of electrochemical cell. Non-spontaneous reactions usually require electrical energy to operate.

The general form of the reaction can be written as:

Reactants ⇌ Products - Electrical Energy Spontaneous⟶⟵Non-spontaneous (1)

Electrolytic cell is a device through which conversion of electrical energy is done to chemical energy or it can be vice versa. These types of cells usually comprise two electronic or metallic conductors also known as electrodes and these are held apart or remain in the contact of an electrolyte (q.v.), generally a fused or dissolved ionic compound.

Connection of all these electrodes with the support of the source of the direct electric current is one of them and it remains negatively charged (cathode) or the other one is positively charged. These come together with one or more electrons that come along and a part of their charge is lost by the charge and it becomes ions with neutral atoms or lower charge or it might be molecules at that particular time. 

Negative ions transfer the positive anode (electrode) and transmit one as well as more electrons in it. This comes out as fresh neutral or ions particles. The whole effect of these two processes happens as per the transmission of the electrons. Vedantu has provided a detailed explanation of the term so that the students are able to understand it thoroughly and they can attempt the questions based on it without a hassle.

Galvanic Cell and Electrolytic Cell Comparison

Electrolytic cells are those which work on chemical energy by utilizing electrical power from the system. The electrolytic cells work on a similar mechanism as that of the Galvanic cells. Both the cells mainly consist of two half cells, such as the oxidation half cell and redox half cell. However, the flow of electrons is a little different. Still, the cathode and anode definition remains the same, where reduction takes place at the cathode and oxidation occurs at the anode. Because both half-reactions' directions have been reversed, the sign, but not the magnitude, of the cell potential has been changed.

Electrolytic cells are very similar to voltaic (galvanic) cells because both require a salt bridge, both have a cathode and anode side, and both have a consistent flow of electrons from the anode to the cathode. However, there are also striking differences between the two cells. The main differences are outlined below:

Vedantu has compared electrolytic and galvanic cells as these two sometimes comprise a single question based on the comparison or you can also get short notes on them separately. Once the students are able to obtain comprehension, then they will be able to attempt the related questions if they are not related to the topics directly. After this simple comparison between these two, you can also get a question on hardcore difference, not an issue as Vedantu is going to explain the difference for the students in the below paragraphs. So, your preparation will be strong enough, just hold the topic explained by Vedantu in your mind thoroughly.

Difference Between Galvanic Cell and Electrolytic Cell

Electrolytic Cell

Let us take an example to understand clearly about Electrolytic cells. When molten Sodium chloride undergoes decomposition, it gets converted into metallic sodium and Chlorine gas.

\[2Nacl \rightarrow 2 Na + Cl_{2}\]

If we put carbon electrodes with both ends c to the molten NaCl in a container, the electrolysis will occur when an additional energy source is applied. Electrons' flow will take place from the anode and neutralize the Na+ ion at the cathode end.

\[Na^{+} + e  \rightarrow Na\]

Note that the oxidation site is still the anode and the site of reduction is still the cathode, but the charge on these two electrodes is reversed. The anode is now positively charged and the cathode has a negative charge. The conditions under which the electrolyte cell operates are significant. The substance that is the strongest reducing agent (the substance with the highest standard cell potential value in the table) will undergo oxidation. The substance that is the strongest oxidizing agent will be reduced. If an aqueous sodium chloride solution were used in the above system, hydrogen would undergo reduction instead of sodium because it is a stronger oxidizing agent than sodium.

Electrolytic Cell Application

• Electrolytic cells are mainly involved in hydrogen gas and oxygen gas production by water utilization.

• In the metal extraction process, these are very helpful. Exp - Aluminium extraction from bauxite

• Electroplating is another feature of the electrolytic cell. This is the process in which a protective covering of a specific metal is done on another metal.

• Electrowinning is also another application in which metal extraction is done from the raw ore. The leeching phenomenon is generally followed in this process.

• To remove the impurities from the metal, the electrorefining method is followed.

• During heavy metals like copper, zinc, and aluminium and the highest purity level, electrolytic cells are used.

Properties of Galvanic and Electrochemical Cells

The galvanic cell converts chemical energy into electrical energy. An electrolytic cell can convert electrical energy to chemical energy. A salt bridge is a connecting link between the two sections that are placed in two different containers. Oxidation reaction takes place at the anode region and the redox reaction in the cathode region. The external cell provides the necessary electrons that enter via cathode and release via anode.

Working Principle of an Electrolytic Cell

Electrochemical cells are devices based on the principle that when a chemical oxidation-reduction reaction occurs, electrons are being transferred from one chemical species to another. In a galvanic cell, the electrons are usually allowed to flow outside of the device in a circuit to operate some electrical device. In the other type of electrochemical cell, called an electrolytic cell, the reverse process occurs. Electrons in the form of an electric current are deliberately being pumped through the chemicals in the section to force an electric current oxidation-reduction reaction to take place. An example of an electrolytic cell is the setup used to decompose water into hydrogen and oxygen by electrolysis.

Conclusion

Hence, Vedantu subject matter experts have described all the ins and outs of the electrolytic cells chapter. The prime aim of Vedantu is always to make an addition to the knowledge of the students along with a promise to help them obtain great marks academically. With our notes, they are able to know what an electrolytic cell is, its definition, its application in varied sectors, its properties, and the working principles of electrolytic cells. So, if you are also eager to be a part of Vedantu tuitions, then it is really simple with a few clicks of the mouse. All you need to access us via our website or you can simply download the mobile application.