Which of the following methods is used to prevent corrosion?
- Painting
- Electroplating
- Sacrificial electrode of another metal
- All of these
The Correct Option is D
Solution and Explanation
Correct answer: All of these
Explanation:
All the mentioned methods are effective in preventing corrosion:
- Painting: Creates a protective barrier that prevents moisture and oxygen from reaching the metal surface.
- Electroplating: Coats the metal with another metal (like chromium or zinc) to protect it from corrosion.
- Sacrificial electrode: A more reactive metal is used, which corrodes instead of the protected metal (e.g., using zinc to protect iron — called galvanization).
Hence, the correct answer is All of these.
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