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Electro Chemical Series

Electrochemical series is also known as electromotive series. It is defined as a serial arrangement of the ions and metallic elements according to their chemical reactivity or electrode potentials which are determined under the specified conditions. The order of this series shows the nature of one metal to reduce the ions of other metal which are below it in the series. By this, we can say that the most reactive metals are at the top and the less reactive are at the bottom.

Electrochemical Series of Metals:

The rate of ionization is different for different metals. For e.g., when the metal like sodium is exposed to the air, combine instantly with the oxygen that are present in the air. On the other hand, metals like gold when exposed in the air for a long time don’t have the tendency to react with air.

Based on this with which metals form their ions by losing the electrons, the metals are arranged in the series known as Metal Activity Series.

Features of Electrochemical Series:


In this electrochemical series, the lower elements have the tendency to lose their charge to become neutral so they get discharged more easily as compared to the above one in the series.

In the series, as a reference point, Hydrogen is included.

As we go down in the series, the reducing power and the electropositive power decrease whereas the oxidizing power and the electronegative power increase upwards.

Significance of Electrochemical Series:

This series is helpful in the prediction of most of the electrochemical reactions.

  • The elements which have high electropositivity and high electro negativity are known as highly reactive elements.
  • The metals which are situated above hydrogen displace hydrogen from acids while below it do not displace hydrogen from acids.
  • In the series, each element has the tendency for displacing any other element which are situated below it from a solution of its salt. For e.g., if we add zinc metal in the solution of copper sulfate, copper is replaced by zinc because in the series, zinc is at above position as compared to copper.
  • When one metal ion replaces other solution from its solution, the element which gives up the electrons easily for the formation of ion will be in the solution.