The reactivity series and the electrochemical series are related concepts but they are not exactly the same.
The reactivity series is a list that ranks metals in order of their reactivity. It is based on how readily metals react with water or acids to form metal salts and release hydrogen gas. The reactivity series helps to predict the outcome of displacement reactions, where a more reactive metal can displace a less reactive metal from its salt solution.
The electrochemical series, on the other hand, is a list that ranks substances in order of their tendency to undergo reduction or oxidation reactions. It is based on the standard electrode potentials, which measure the potential difference between an electrode and a standard hydrogen electrode (SHE). The electrochemical series helps to determine the direction of electron flow in a redox reaction and predicts the voltage or electrical potential generated by a cell.
Conclusion:- While both the reactivity series and the electrochemical series involve the ranking of substances, the reactivity series focuses on the reactivity of metals with water and acids, while the electrochemical series focuses on the tendency of substances to undergo redox reactions and generates electrical potential. The reactivity series is more specific to metals, whereas the electrochemical series can include both metals and non-metals.