Explain the following methods to protect metals from corrosion: a. Ga

1.	Explain the following methods to protect metals from corrosion: a. Galvanization b. Passivation
Answer» a. Galvanization: 1. The rusting of iron can be prevented by coating the metal surface with another metal such as zinc,thatis oxidized in preference to iron. This process is called galvanization. 2. If the zinc layer is scratched, even then it protects iron from corrosion as long as Fe and Zn are in contact. If Fe is oxidized to Fe²⁺, then Zn immediately reduces Fe²⁺ back to Fe. b. Passivation: The surface of metal is treated with strong oxidizing acid such as concentrated nitric acid and a thin preventive layer of oxide is formed on the surface of metal. Thus, the surface is made inactive. This is process is called as passivation.

Explain the following methods to protect metals from corrosion: a. Galvanization b. Passivation

Answer»

a. Galvanization:

1. The rusting of iron can be prevented by coating the metal surface with another metal such as zinc,thatis oxidized in preference to iron. This process is called galvanization.

2. If the zinc layer is scratched, even then it protects iron from corrosion as long as Fe and Zn are in contact. If Fe is oxidized to Fe²⁺, then Zn immediately reduces Fe²⁺ back to Fe.

b. Passivation: The surface of metal is treated with strong oxidizing acid such as concentrated nitric acid and a thin preventive layer of oxide is formed on the surface of metal. Thus, the surface is made inactive. This is process is called as passivation.

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