An electrochemical cell is constructed with a zinc metal anode in contact with a 0.052 M solution of zinc nitrate and a silver cathode in contact with a 0.0042 M solution of silver(I) nitrate.What is the value of Q to use in the Nernst equation for this cell?

Question

Quizplus · Accepted Answer

The Nernst equation is:$$E = E° - \frac{RT}{nF} \ln Q$$where Q is the reaction quotient. For the given cell, the reaction is:$$Zn(s) + 2Ag^+(aq) → Zn^{2+}(aq) + 2Ag(s)$$The reaction quotient is:$$Q = \frac{[Zn^{2+}]}{[Ag^+]^2}$$Substituting the given concentrations into the reaction quotient, we get:$$Q = \frac{0.052}{0.0042^2} = 2.9 	imes 10^3$$Therefore, the value of Q to use in the Nernst equation for this cell is 2.9 × 10^3.

An Electrochemical Cell Is Constructed with a Zinc Metal Anode