Cathodic Protection Tester Practice Exam

What phenomenon occurs when current flows in an electrochemical corrosion cell?

1. Reduction at the anode

2. Oxidation at the anode

3. Neutralization at the cathode

4. Resistance increases at the anode

The correct answer is: Oxidation at the anode

In an electrochemical corrosion cell, the phenomenon that occurs when current flows involves oxidation at the anode. During this process, metal atoms lose electrons and transform into positively charged ions, which then enter the electrolyte. This loss of electrons is a defining characteristic of oxidation, effectively contributing to the corrosion of the metal. At the same time, the electrons that are released during oxidation flow towards the cathode, where reduction occurs. This interconnected flow of electrons between the anode and cathode is what drives the current in the electrochemical cell. Therefore, understanding that oxidation occurs specifically at the anode clarifies why this choice accurately describes the process happening within the cell during operation.