What is produced when O2 reacts with water during corrosion of iron?

When oxygen reacts with water during the corrosion of iron, hydroxide ions are indeed produced. This process is part of the electrochemical reaction that occurs when iron is exposed to both moisture and oxygen. In this environment, iron oxidizes, where it loses electrons and goes into solution as iron ions.

Oxygen from the environment then reacts with water and the electrons provided by the oxidizing iron, leading to the formation of hydroxide ions. This increase in hydroxide ions plays a significant role in the corrosion processes associated with iron, as it contributes to the formation of iron oxide, commonly known as rust.

The production of hydroxide ions is crucial as it influences the pH of the surrounding environment and the further corrosion process. This is particularly relevant in the establishment of a corrosion cell where the presence of hydroxides can change the local conditions and affect the reactivity of iron. Therefore, the formation of hydroxide ions is a significant outcome of the interaction between oxygen and water in the context of iron corrosion.