Let's analyze the chemical reactions at the anode to match them with the appropriate cell:
Anodic Reactions:
A.
Zn(Hg)+2OH−⟶ZnO(S)+H2O+2eThis reaction involves zinc in the presence of mercury, which is characteristic of the Mercury cell.
B.
2H2(g)+4OH−⟶4H2O(l)+4e This reaction involves hydrogen, which is typical for a Fuel cell where hydrogen gas is oxidized.
C.
Zn(S)⟶Zn2++2eThis reaction involves the oxidation of solid zinc, common in Leclanche cells (which include dry cells).
D.
Cd(S)+2OH−⟶CdO(S)+H2O(l)+2eThis reaction involves cadmium, which is characteristic of the Nickel Cadmium storage cell.
This reaction involves cadmium, which is characteristic of the Nickel Cadmium storage cell.
Matching Anodic Reactions with the Cells:
Now, let's match the anodic reactions with the given cells:
Hence, the correct matching option is:
Option D:
A=S‌‌B=P‌‌C=Q‌‌D=R