Question

What is anode and cathode used in the above cell?

• A. Anode $-Zn(Hg)$, Cathode $-HgO$
• B. Anode $-Zn$, Cathode $-HgO$
• C. Anode $-Zn$, Cathode $-HgO$ and carbon
• D. Anode $-Zn(Hg)$ amalgam, Cathode $-HgO$ and carbon

Answer 1

Answer: (D)

Zinc-mercury amalgam acts as anode and a paste of $HgO$ and carbon as cathode in the mercury cell. The electrolyte is the paste of $KOH$ and $ZnO$.