JSS 2: RUSTING

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                              Rusting 

Rusting is also known as corrosion of iron. It is defined as the interaction of Iron with air and water to produce rust

When iron is exposed to air and moisture, its surface gradually corrodes and converts into a brown mass. This brown mass is called rust and this phenomenon is known as rusting. 

        Conditions for rusting of iron 

1. Presence of water 

2. Presence of air (Oxygen)

The iron reacts with water and oxygen to form hydrated iron(III) oxide, [Fe₂O₃] which we see as rust.

The corrosion of metals results from the combined action of atmospheric oxygen and water. The most important example of metallic corrosion is that of iron.

             Prevention of Rusting

There are several ways of preventing the rusting of iron:

1. Painting: Applying paint on iron

2. Greasing: Applying grease on iron

3. Galvanizing: Iron is coated with zinc 

4. Electroplating: Iron is coated by other metals that will not rust. Eg copper, tin, chromium, gold, silver.

                  Rusted Roofing sheets

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