Zinc coating on iron provides protection by

Zinc coating on iron provides protection by

• A. sacrificially corroding
• B. blocking oxygen completely
• C. forming an impermeable layer
• D. melting away

Answer: (A)

Zinc coating protects iron through sacrificial protection: zinc is more reactive than iron, so in a damp environment the zinc coating corrodes first, acting as a sacrificial anode. As zinc loses electrons, it forms zinc ions and protective compounds on the surface, while the iron underneath stays shielded from rust. If the coating is scratched, nearby zinc still corrodes first, continuing to protect the iron. This mechanism isn’t about blocking oxygen completely or creating an impermeable layer, and it doesn’t involve melting away—it gradually supplies corrosion to itself to spare the iron.

Zinc coating protects iron through sacrificial protection: zinc is more reactive than iron, so in a damp environment the zinc coating corrodes first, acting as a sacrificial anode. As zinc loses electrons, it forms zinc ions and protective compounds on the surface, while the iron underneath stays shielded from rust. If the coating is scratched, nearby zinc still corrodes first, continuing to protect the iron. This mechanism isn’t about blocking oxygen completely or creating an impermeable layer, and it doesn’t involve melting away—it gradually supplies corrosion to itself to spare the iron.