Final answer:
The dissolution of iron (II) hydroxide involves its reaction with oxygen and water to form iron (III) oxide hydrate or rust, which is illustrated by a balanced chemical equation. Unlike protective layers, rust perpetuates the corrosion of iron.
Step-by-step explanation:
The dissolution of iron (II) hydroxide involves it reacting with oxygen and water to form iron (III) oxide hydrate, commonly known as rust. This process is represented by the following balanced chemical equation:
4Fe²+ (aq) + O₂(g) + (4 + 2x) H₂O(l) → 2Fe₂O₃ xH₂O(s) + 8H+ (aq)
The stoichiometry of the hydrate varies, as indicated by the variable 'x' in the compound formula. It's important to note that ferric hydroxide [Fe(OH)3] is highly insoluble, and the presence of complexing agents and the pH of the solution can affect the solubility of metal ions. Unlike protective patinas, rust does not stop the corrosion process, leading to continuous deterioration of the iron.