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Questions
Explain the terms Corrosion
Explain the term "corrosion" with an example.
Solution 1
Corrosion is defined as a process where materials, usually metals, deteriorate as a result of a chemical reaction with air, moisture, chemicals, etc. For example, in the presence of moisture, iron reacts with oxygen to form hydrated iron oxide.
\[\ce{4Fe + 3O2 + H2O → 2Fe2O3.nH2O}\]
Solution 2
Corrosion is a process where a refined metal is oxidised by atmospheric oxygen to form a more stable compound, such as oxides. The metal gradually degrades during the corrosion process. Iron rusting is a good example of corrosion, where the iron is converted to iron oxide. Millions of dollars are spent annually to prevent rusting on bridges and other monuments.
Solution 3
Corrosion is the process by which metal corrodes when it comes into contact with its surroundings, such as moisture, air, and acids. For example, a powdered (brown) coating on iron objects such as iron railings.
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