The mass of three different metal electrodes, each from a different galvanic cell, were determined before andafter 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, giventhe 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 wereanode(s) and which were the cathode(s)

• Avoltaic or a galvanic cellis an electrochemical cell which derives the electrical energy from the spontaneous redox chemical reactions which occur inside the cell.
• A galvanic cell usually contains two different metals which are dipped in an electrolytic solution or of an individual half-cells having different metals and their ions present in the solution, joined by a salt-bridge or dividedby a porous membrane.

The active electrode which is found to lose mass during redox reaction in a cell is termed as anode and the electrode which gain mass during redox reaction is termed as cathode.Since the electrodes \(A\) and \(C\) were found to have change in mass therefore they are active electrodes, whereas the electrode \(B\) does not experience any weight change, thus we can say that electrode \(B\) is an inert electrode. \(D\) to have increase in mass which means reduction occurred at this electrode. Therefore, electrode A was acted as cathode. The electrode labelled \(C\) was found to have lost mass which means oxidation occurred at this electrode. Therefore electrode \(C\) was anode.