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Corrosion of metals and their protection - Coggle Diagram
Corrosion of metals and their protection
Rust : A reddish- or yellowish-brown flaking coating of iron oxide that is formed on iron or steel by oxidation
Corrosion is a natural process that converts a refined metal into a more chemically stable form such as oxide, hydroxide, or sulfide.
The more reactive a metal the more rapidly it corrodes
Anhydrous calcium chloride removes moisture from the air which makes it no air and water and no rusting occurred
Boiling the water removes dissolved air on the oil layer on top prevents air from dissolving inwater again. Therefore no air and water and no rusting will occur
Distilled water contains dissolved air there both water and air are present and rusting will occur.
Rusting : Fe(s) -> Fe2+ (aq) + 2e-
Factors that speed up rusting
Presence of acidic poollutants
Presence od soluble ionic compounds
High temperature
Attachment of less metals to iron
Scratched bent or sharp are of an iron-made object
Methods to protect iron from rusting
Applying a protective layer (Coating with paint plastic oil or grease)
Coating with another metal
Tin-plating
Electroplating
Cathodic protection
Sacrificial protection
Galvanized iron
Attaching zinc blocks to ship bulls
Connecting magnesium blocks to underground piplines
Use alloys of iron
The corrosion resistance of aluminum
protective oxide layer on aluminium
Thickening the protective oxide layer on the aluminum