Question

Which of the following option(s) is/are incorrect regarding electrochemical series ?

• A. Polarity of the electrode system and the electrode reaction can be easily predicted.
• B. Negative value of $E^{\circ }$ signifies that the redox couple is a stronger oxidising agent than the $H^{+}/H_2$ couple
• C. Spontaneity and feasibility of the cell can be easily predicted.
• D. All of the above.

Answer 1

The correct option is B Negative value of $E^{\circ }$ signifies that the redox couple is a stronger oxidising agent than the $H^{+}/H_2$ couple

Observations from Electrochemical Series:

1. Negative value of $E^{\circ }$ signifies a high tendency to get oxidised. So, the redox couple is a stronger reducing agent than the $H^{+}/H_2$ couple
2. Positive value of $E^{\circ }$ signifies a high tendency to get reduced. So, the redox couple is a stronger oxidising agent than the $H^{+}/H_2$ couple

Application of Electrochemical Series:

1. The relative oxidising and reducing abilities of the elements can be compared easily.
2. It helps in the selection of electrode assemblies to construct the galvanic cells of desired EMFs.
3. Polarity of the electrode system and the electrode reaction can be easily predicted.
4. Spontaneity and feasibility of the cell can be easily predicted as the electrode potential value can be used to calculate the cell potential. Value of cell potential must be positive for spontaneous and feasible reactions of a cell.