Cathodic Protection Tester Practice Exam

How do more active metals in a galvanic series behave compared to noble metals?

1. They corrode less easily

2. They have a higher resistance to corrosion

3. They have a tendency to corrode more easily

4. They do not corrode at all

The correct answer is: They have a tendency to corrode more easily

The correct response highlights a fundamental principle of electrochemistry related to the galvanic series, which ranks metals based on their electrochemical activity. More active metals—those that are higher on the galvanic series—are more anodic, meaning they tend to lose electrons more readily than their noble counterparts. This characteristic makes them more prone to oxidation and, consequently, to corrosion. Noble metals, which are lower on the galvanic series, exhibit a higher resistance to corrosion because they do not lose electrons as easily. They tend to be more stable and less reactive in corrosive environments. Therefore, the behavior of more active metals aligns with a tendency to corrode more easily when compared to noble metals, confirming the rationale behind the selected answer. Understanding these differences is crucial for the selection of materials in environments where corrosion is a risk.