In electrochemical corrosion of metals, the metal undergoing corrosion:

Options

A. acts as anode
B. acts as cathode
C. undergoes reduction
D. None

Answer

**Step-by-Step Solution:**

1. **Understanding Electrochemical Corrosion:**
- Electrochemical corrosion is a process where metals corrode due to electrochemical reactions. It involves the transfer of electrons between the metal and its environment.

2. **Identifying the Metal Undergoing Corrosion:**
- The metal that is undergoing corrosion is the one that gets oxidized. Oxidation is the loss of electrons.

3. **Role of Anode and Cathode:**
- In an electrochemical cell, oxidation occurs at the anode, and reduction occurs at the cathode. Therefore, the metal that is oxidized during corrosion acts as the anode.

4. **Oxidation Process:**
- When the metal (let's denote it as M) undergoes oxidation, it loses electrons and transforms into a positively charged ion (N⁺). The reaction can be represented as:
\[ \text{M} \rightarrow \text{N}^+ + \text{e}^- \]
- Here, M is the metal in its elemental form, and N⁺ is the metal ion formed after oxidation.

5. **Reduction Process at the Cathode:**
- In the case of corrosion, typically oxygen is reduced at the cathode. For example, oxygen in the air (O₂) is reduced to form water (H₂O), which involves gaining electrons.

6. **Conclusion:**
- Since the metal undergoing corrosion is oxidized and acts as the anode, we conclude that in electrochemical corrosion, the metal that undergoes corrosion always acts as the anode.

**Final Answer:**
In electrochemical corrosion of metals, the metal undergoing corrosion acts as the anode.

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