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Question
The chemical reaction involved in the corrosion of iron metal is that of:
(a) oxidation as well as displacement
(b) reduction as well as combination
(c) oxidation as well as combination
(d) reduction as well as displacement
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Solution
(c) oxidation as well as combination
In the corrosion of iron metal, iron metal reacts with water and oxygen and forms hydrated oxide called rust.Addition of oxygen to the metal is a oxidation reaction.
4Fe + 3O2 + 2xH2O → 2Fe2O3.xH2O
Since iron metal combines with water and oxygen to corrode, it is also a combination reaction, in which iron metal, water and oxygen combine to form a single compound.
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