If the cell emf of a Zn-Cu cell is 0.80 V

Question

when the concentration of Zn2+ is 2.0M, what is the concentration of Cu2+?

Answer 1

Zn + Cu^2+ ==> Cu + Zn^2+
Eo cell = Eo oxdn Zn Eo redn Cu = about 1.1 v but you need to look up the numbers and use those in your text.
Then Ecell = Eocell -(0.0592/2)log Q where
Q = (Cu)(Zn^2+)/(Zn)(Cu^2+).
Substitute Zn^2+ and Ecell and solve for (Cu^2+).

Answer 2

1.5x10^-10M