16. Galvanized iron is steel sheet that has been coated with zinc; ""tin"" cans are made of steel sheet coated with tin. Discuss the functions of these coatings and the electrochemistry of the corrosion reactions that occur if an electrolyte contacts the scratched surface of a galvanized iron sheet or a tin can.​

explanation below

Explanation:

Zinc plating or Galvanization is mostly used to provide protection against water and certain elements in the air, which causes corrosion. Zinc coating is mostly applied to steal and iron because these metals are known to rust easily.  

When you scratch a galvanized pail (Metal Buckets with Handles), the pail will not undergo corrosion but the zinc used in the process will be oxidized. When some part of the zinc is oxidized, it is known to absorb CO2 from the air to form zinc oxide-carbonate, which is a tightly adhering coating.

In the case of tin can, a tin-plated iron, the tin is known to have a higher reduction protection that the iron and can remain reduced as the metal. When the surface is scratched, the iron will oxidize instead of the tin.  

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