Electrochemical series is an arrangement of element on the basis of their increasing electrode potential. The electrode potential is measured comparatively against the hydrogen electrode.

The Hydrogen electrode is taken as a standard electrode against which the electrode potential of any element is measured.

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Electrochemical series is also called activity series which is the arrangement of elements in order of their increasing electrode potential values. Principle of arrangement of series is by measuring the potential of various electrodes versus standard hydrogen electrode (SHE). Its significance is that it helps us to pick out the elements easily on the basis of good oxidizing agents and good reducing agents.

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