Given a Leclanché battery in an acid medium:
MnO2 /MnO(OH) and Zn2+/ Zn
Write the equations of the reactions at the electrodes!
A natural reaction takes place between the strongest reducing agent Zn and the strongest oxidising agent MnO2:
MnO2+ H+ + e-
MnO(OH)
Zn Zn2+ + 2 e-
Which is the negative battery terminal?
The zinc metal is the strongest reductant, so the negative terminal is the zinc electrode.