A student hypothesised that polishing the zinc, Zn, electrode in an Fe-Zn galvanic cell would increase the current produced by the cell - VCE - SSCE Chemistry - Question 10 - 2021 - Paper 1

The most valid method of testing the hypothesis is to measure the change in mass per unit time of the Fe electrode when the Zn electrode is polished. This method directly correlates to the current produced in the galvanic cell as it accounts for the impact of polishing on the electrochemical reaction. By comparing the Fe electrode's mass change before and after polishing, one can infer the effect of the polished surface on current production, demonstrating a clear cause-and-effect relationship.