Question

Define electrochemical series. Write its applications.

Answer 1

In electrochemical series the chemical elements are arranged in order of their increasing standard electrode potential. The electrochemical series is also known as activity series.

Complete step by step answer:
The electrochemical series is defined as the arrangement of the elements in their increasing order of electrode potential values. The electrochemical series is sometimes referred to as activity series. The electrochemical series has been established by measuring the electrode potential compared to standard hydrogen electrodes.
The electrodes whether metal or non-metal in the electrochemical series are arranged on the basis of their standard reduction or oxidation potentials.
The applications of electrochemical series are shown below.
(1) To identify the oxidizing and reducing strength of metals and non-metals: The electrochemical series helps to identify the oxidizing agent and reducing agent. The elements present at the top of the electrochemical series are considered as good oxidizing agents and those which are present below the electrochemical series are considered as good reducing agents.
(2) Calculation of standard emf of electrochemical cell: The standard emf of the electrochemical cell is defined as the sum of the two half-cell of standard reduction potential: reduction half-cell and oxidation half-cell.
(3) The electrochemical series helps to predict the feasibility of Redox reaction: When the free energy change is negative, then the redox reaction occurs simultaneously.

Note:
The relation between the Gibbs free energy and the cell emf is shown below.
$\Delta {G^0} = nF{E^0}$
Where,
$\Delta {G^0}$ is Gibbs free energy
n is the number of electrons.
F is the Faraday constant
${E^0}$ is the cell emf