The mass of three different metal electrodes, each from a different galvanic cell, were determined before and after the current generated by the oxidation-reduction reaction in each cell was allowed to flow for a few minutes. The first metal electrode, given the label A, was found to have increased in mass; the second metal electrode, given the label B, did not change in mass; and the third metal electrode, given the label C, was found to have lost mass. Make an educated guess as to which electrodes were active and which were inert electrodes, and which were anode(s) and which were the cathode(s).

Give the notation for a voltaic cell whose overall cell reaction is Mg(s)+2Ag+(aq)Mg2+(aq)+2Ag(s) What are the half-cell reactions? Label them as anode or cathode reactions. What is the standard cell potential of this cell?

As an example of an electrolytic cell, the text states: Sodium chloride is electrolyzed commercially in an apparatus called the Downs cell to produce sodium and chlorine. This is a high-temperature operation; the electrolyte is molten NaCl. Write the half-reaction equations for the changes taking place at each electrode. Is the electrode at which sodium is produced the anode or the cathode? The Downs cell electrolyzes molten melted sodium chloride, producing sodium and chlorine.