So in this reaction:
Ag(s) + Fe(+3) --> Ag(+) + Fe(+2)
we are given 20 grams of Ag(s) to start off with. How do we find how many electrons are transfered in the reaction. And how many grams of Fe(+2) is formed.
*for the latter, i think that we can calculate it through simple one-to-one mole ratio, but I am not completely sure if that's right.
The balanced equation is
3Ag(s) + Fe^+3(aq) ==> Fe(s) + 3Ag^+(aq)
Three electrons are transferred for each Fe^+3 transformed to Fe solid. I presume you doing this with some device, like a battery, to make the reaction go. I don't think it will occur spontaneously.