Exam Question

Corrosion is an electrochemical process involving the degradation of a material, typically a metal, due to its reaction with its environment. The process requires an anode, a cathode, an electrolyte, and a metallic path. The rate of corrosion is influenced by several environmental factors. The effects of the specified factors are as follows:
### (a) Effect of Dissolved Oxygen (4 Marks)
Dissolved oxygen is a critical factor in the corrosion of metals, particularly iron and steel, in neutral or near-neutral aqueous environments. Its primary role is to act as a cathodic depolarizer.
* **Electrochemical Mechanism:**