Battery equations?

[impulsebro89]

Hello!
Can someone check to see whether my battery equations are correct or not? I've seen so many iterations of these equations that I don't know what's real anymore 

Button cell
Anode: Zn(s) + 2OH-(aq)- --> ZnO(s) + H2O(l) + 2e-
Cathode: Ag2O(s) + H2O (l) + 2e- --> 2Ag(s) + 2OH-(aq)
Overall: Zn(s) + Ag2O(s) --> ZnO(s) + 2Ag(s)

Dry Cell
Anode: Zn(s) --> Zn2+(aq) + 2e-
Cathode: 2MnO2(aq) + 2H+ + 2e- --> Mn2O3(aq) + H2O(l)
Overall: ?

For the dry cell I've seen so many versions of the cathode; is it ok to write this one down in the exam? Also what is the overall equation for it?

Thanks

[infinityandbeyond]

I guess if you got that from a reliable source, the examiners will accept it. I believe they will accept many forms of the half equations.

The overall equation for dry cell is:
Zn(s) + 2MnO2(aq) + 2H+--> Zn2+(aq) Mn2O3(aq) + H2O(l)

Simply just integrate the cathode and anode half equations together, cancelling 2e- from both sides.

[impulsebro89]

Cool thanks! I wasn't sure if that overall equation was correct or not because the cathode equation for the dry cell is like a simplified version without the spectator ions.