Considering how sensitive iron sulfides are to changes of local electrochemical conditions, we expect that different phases may exist under the experimental conditions tested here. Key enzymes in the WL pathway are also known to be sensitive to O2 and to electrochemical conditions. A specific mineral phase or cluster may have facilitated the formation of acetic acid. Moreover, the experimentation here was performed in a specific type of reactor that was designed to simulate the vent-ocean interfacial electrochemical conditions and the long period of residence for the experiments may also be the reason for the detection of acetic acid. Besides that, different phases show more stability under different potential, and some of those may prevail after the 12 hours of experiments, which can explain the different pattern observed under -500 mV.