Question

Irons nail has a brown layer why is it so plzzzz give me a explained ans

Answer 1

Iron nails obtain a brownish layer when it is left open for a few days. This property is known as corrosion. Thia happens when the iron comes in contact with air, thereby reacting with oxygen, forming iron oxide or rust.
Equation:
Fe + O2 = Fe2
Hope it helps. THANK YOU. :)

Answer 2

It is due to corrosion of iron nail.

It occurs as iron comes in contact with water (any state) and oxygen to form iron oxide that is FeO.

To prevent:

1) apply paint on iron nail(or may b any other article made kg iron)

2) apply Greece

3) also, oil can work in preventing corrosion of iron (nail or any other article)