You might have seen reddish orange patches on iron at times. These patches are known as rust. Rust forms on iron because of oxidization, when the oxygen of the air burns the surface of the iron. It can be rubbed off in the form of fine powder just like ash.
Rusting damages the iron; it spoils the appearance of cars and buildings and the damage it causes costs a lot of money to be set right. However, rust is not that bad. It is actually beneficial to us in many ways.
Rust mixes with the soil, giving it a good brown or red colour. When powdered rust dissolves in water, it is taken up by plants and this eventually contributes to their green colour. Finally, through water and plants, we take iron into our bodies to give us the red colour of our blood.
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