Question

Define standard emf of a cell.

Answer 1

Hint: We have to know that the electrochemical cell is mainly used to produce current by using the chemical reaction. The electrochemical cell will transform chemical energy into electrical energy. The chemical reaction undergoes the exchange of electrons which is essential for operating the electrochemical cell. And this type of reaction is known as redox reaction. The cell is differentiated on the basis of its voltage. The electrochemical cell is mainly divided into two types and that is, denial cell and galvanic cell.

Complete answer:
We need to remember that the cell potential is the distinction between the electrode potentials, which is the reduction potential of anode and cathode. It is known as standard electromotive force or standard emf of the cell. That time, there will not pass current through the cell. And it is related to the ability of an element to release or accept the electrons. In the case of a galvanic cell, the difference in potential between the two electrodes present in the galvanic cell is known as cell potential. And the cell potential is measured in terms of volts.
By using the cell EMF, we can determine the cell whether it is galvanic or not.

Note:
We need to remember that the standard emf of a cell can be found by breaking the reaction into reduction and oxidation half-cell reaction. Further calculate the standard reduction potential present in the half - cell reaction. Next find out the total EMF present in the cell by considering the redox reaction. The electromotive force is also known as cell EMF, which is equal to the net voltage present between reduction and oxidation half – cell reaction occurred between two redox half – reaction.