A galvanic cell is constructed as Zn(s) | Zn (aq, 1.0 M) || Cu (aq, 1.0 M) | Cu(s)
CHEMISTRY · Single correct · AP · Chemistry · Thermodynamics and Electrochemistry · Thermodynamics and Electrochemistry
Problem
A galvanic cell is constructed as
Zn(s) | Zn2+ (aq, 1.0 M) || Cu2+ (aq, 1.0 M) | Cu(s).
The concentration of Zn2+ in the anode compartment is increased to 2.0 M while all other conditions remain the same. Which of the following best describes how the cell potential immediately after the change compares with the standard cell potential?
(a) It is larger because adding Zn2+ decreases the value of Q, increasing Ecell according to the Nernst equation.
(b) It is unchanged because the cell potential depends only on the standard reduction potentials of the two half-reactions.
(c) It is smaller because adding Zn2+ increases the value of Q, moving the system closer to equilibrium.
(d) It becomes negative because the additional Zn2+ reverses the spontaneous direction of the cell reaction.