Question

useful effect of corrosion

Answer 1

We know that metals are highly reactive elements due to less number of valence electrons therefore they tend to lose electrons during chemical reactions. Corrosion is also a chemical reaction in which metal reactions with atmospheric moisture and oxygen gas to form metallic oxides. That is the reason, metals corrode quickly.  Metallurgy is the process of conversion of metallic ores to metal as metals are usually found in combined state in nature. These pure metals are used for various industries.

The deterioration of metallic surface due to corrosion reduces the efficiency of metallic equipments which causes financial lose to industries. Therefore it’s important to note the causes, forms and effects of corrosion. 

Answer 2

Useful effect of corrosion.

[1] Surface corrosion forms an oxide layer which further protects the inner metal form corrosion.

[2] Some metals like zinc are used as sacrificial anodes to prevent corrosion to other metal.

[3] The principle on which primary batteries work.

In which one metal corrodes preferentially to another when both metals are in electrical contact, in the presence of an electrolyte.