Determine whether or not each metal, if coated onto iron, would prevent the corrosion of iron. a. Mg

Verified step by step guidance

1. Understand the concept of galvanic corrosion: When two different metals are in contact in the presence of an electrolyte, the more reactive metal will corrode preferentially, protecting the less reactive metal.
2. Identify the position of magnesium (Mg) and iron (Fe) in the electrochemical series: Magnesium is more reactive than iron.
3. Determine the standard electrode potentials: Magnesium has a more negative standard electrode potential compared to iron, indicating it is more likely to oxidize.
4. Apply the concept of sacrificial anode: Since magnesium is more reactive, it will act as a sacrificial anode, corroding instead of iron when both are in contact.
5. Conclude that coating iron with magnesium will prevent the corrosion of iron, as magnesium will corrode preferentially, protecting the iron.

Key Concepts

Corrosion

Corrosion is the process by which metals deteriorate due to chemical reactions with their environment, often involving oxidation. In the case of iron, it typically forms rust (iron oxide) when exposed to moisture and oxygen. Understanding corrosion is essential to determine how different metals can protect iron from this degradation.

Galvanic Series

The galvanic series is a list of metals arranged according to their electrochemical potential in a specific environment, which indicates their tendency to corrode. Metals higher in the series are more noble and less likely to corrode, while those lower are more reactive. Coating iron with a metal higher in the series can provide cathodic protection, preventing iron from corroding.

Cathodic Protection

Cathodic protection is a technique used to prevent corrosion by making the metal to be protected (like iron) the cathode of an electrochemical cell. This can be achieved by applying a more reactive metal (like magnesium) that will corrode instead of the iron. Understanding this principle helps in evaluating whether a metal coating will effectively protect iron from corrosion.