Concentration Cell vs Galvanic cell: Key Differences
Concentration cells have two half cells with the same composition, whereas galvanic cells may or may not have two half cells with the same composition. Electrochemical cells include galvanic cells and concentration cell. In electrochemical cells, a chemical reaction is used to generate electricity or to cause a chemical reaction to occur.
What is a Galvanic Cell?
Using spontaneous redox reactions, the galvanic cell generates electricity through electrochemical reactions. Voltaic cells are synonyms for this type of cell. There are two half cells in the cell, which can be the same composition or different compositions. Electrolytes and electrodes are contained in each half cell. Electrolysis should be performed with the electrode immersed in electrolytic solution. There are times when these electrolytes are completely separate, and there are times when they are separated by only a porous barrier. The movement of ions between two electrolytes is maintained by a salt bridge when the electrolytes are completely separated.
It is important to consider whether the electrodes and electrolytes of this cell are spontaneous or not when preparing it. The electrode potentials of each half cell can be calculated theoretically. An oxidation reaction should be observed on one half of the cell, while a reduction reaction should be observed on the other half of the cell. At the anode, oxidation occurs, while at the cathode, reduction occurs. A galvanic (voltaic) cell generates electricity using the energy released during a spontaneous redox reaction. Direct current is produced by them.
What is a Concentration Cell?
A concentration cell is a type of galvanic cell whose two halves have similar compositions. As a result, we say that the two half cells are equivalent.
Concentration is the only difference between them. Due to the tendency of this cell to attain equilibrium states, it produces very little voltage. When the two half cells reach equilibrium, their concentrations are equal.
By reducing the thermodynamic free energy of the system, the concentration cell produces electricity. The same reaction occurs in both half cells, but in opposite directions due to their similar compositions. By increasing the concentration of the lower concentration cell, and decreasing the concentration of the higher concentration cell, the concentration of the lower concentration cell increases. Electricity generates thermal energy as it flows. Heat is absorbed by the cell as a result of this energy. Concentration cells can be divided into two types:
An electrolyte concentration cell has electrodes made of the same substance, and half cells contain different concentrations of the same electrolyte
Two electrodes (of the same substance) are dipped in the same electrolyte with different concentrations.
What is the Difference Between Galvanic Cell and Concentration Cell?
An electrochemical cell that uses spontaneous redox reactions to produce electricity is called a galvanic cell. The concentration cell, on the other hand, is a type of galvanic cell whose two half cells are similar in composition. Consequently, the main difference between galvanic cell and concentration cell is that galvanic cell may or may not contain the same composition in both half cells, whereas concentration cell has the same composition in both half cells.
In addition, the electrodes of galvanic cells can be made from the same substance or from different substances, while the electrodes of concentration cells can be made from the same substance and concentration or a different concentration. The electrolytes in galvanic cells may be the same or different in each half cell, while concentration cells may be the same electrolyte at a different concentration.
