posted by Anonymous
Both aluminum and zinc are used in "air batteries", those that use oxygen from the air as an oxidizing agent. These reactions take place in one type or the other:
4Al(s) + 3O2(g) --> 2Al2O3(s)
2Zn(s) + O2(g) --> 2ZnO(s)
a) Calculate DeltaG^o for these reactions at 25 degrees C
b) What is the maximum number of kilojoules that can be extracted from one pound (454 g) of each metal?
c) What is the voltage, Eo(cell)of each battery to 3 significant figures?
(Delta Go products) - (delta Go reactants)
For the Al, you have calculated the delta Go in kJ for 2 mols Al2O3 or 4 mols Al. Convert that to 454 g Al Same thought process for the Zn reaction.
Delta Go = -nFEocell