The overall reaction is represented by
Zn(Hg) + HgO(s) ¾® ZnO(s) + Hg(l)
The cell potential is approximately
1 35 V and remains constant during its
life as the overall reaction does not
involve any ion in solution whose
concentration can change during its life
time A secondary cell after use can be recharged by passing current
through it in the opposite direction so that it can be used again A
good secondary cell can undergo a large number of discharging
and charging cycles