Question

A voltaic cell similar to that shown in the figure above is constructed. The electronic device shown at the top of the figure is a volt meter. One electrode compartment consists of a cadmium strip placed in a 1.0 M Ca(NO3), solution, and the other has a copper strip placed in a 1.0 M CUSO4 solution. The overall cell reaction is: Ca(s) + Cu2+ (aq) = Cd2+(aq) + Cu(s) (a) Fill in the information necessary to complete the half reactions that occur in the two electrode compartments. Use the lowest-possible whole-number coefficients. To input an ion surround the ion's element symbol with square brackets and put the ion's charge to the right like this: Al3+ = [A1]3+ (not (Al]+3), and Lit = [LI] + (not (Li]l+ or [Li]+1). Do not use brackets for neutral species. Anode half reaction: () = (aq) + e Cathode half reaction: (aq) + = (s) (b) Figure out which electrode is the anode, which is the cathode, the signs on these electrodes, the direction in which the electrons flow through the volt meter, and the direction in which cations and anions migrate through the salt bridge and solutions. Use this work to pick all of the statements from below which are true. The cadmium electrode is positive and the copper electrode is negative. Electrons flow from the cadmium electrode to the copper electrode through the volt meter. Anions migrate from the 1.0 M Ca(NO3), solution through the salt bridge to the 1.0 M CuSO4 solution The copper electrode is the anode and the cadmium electrode is the cathode. Cations migrate from the 1.0 M CUSO, solution through the salt bridge to the 1.0 M Ca(NO3)2 solution. Anions migrate from the 1.0 M CuSO4 solution through the salt bridge to the 1.0 M Ca(NO3)2 solution. Electrons flow from the copper electrode to the cadmium electrode through the volt meter. The cadmium electrode is the anode and the copper electrode is the cathode. The copper electrode is positive and the cadmium electrode is negative. Cations migrate from the 1.0 M Ca(NO3)2 solution through the salt bridge to the 1.0 M CuSO4 solution.

Answer 1

(a) Anode half reaction : Cd (s) $\rightleftharpoons$ Cd²⁺ (aq) + 2 e^-

Cathode half reaction : Cu²⁺ (aq) + 2 e^-$\rightleftharpoons$ Cu (s)

(b) Correct statements are :

(1.) The cadmium electrode is positive and the copper electrode is negative.

(2.) Electrons flow from the cadmium electrode to the copper electrode through the volt meter.

(3.) Anions migrate from the 1.0 M CuSO₄ solution through the salt bridge to the 1.0 M Cd(NO₃)₂ solution.

(4.) The cadmium electrode is the anode and the copper electrode is the negative.

(5.) Cations migrate from the 1.0 M Cd(NO₃)₂ solution through the salt bridge to the 1.0 M CuSO₄ solution.