Question

Question 8.

Why do the articles made of iron when placed in moist air get covered with reddish-brown, powdery substance? Is this process a physical or chemical change?

Answer 1

Articles made of iron when placed in moist air get covered with a reddish-brown powder called rust. The upper layer of iron reacts with water and oxygen present in the air in the form of moisture and forms a reddish-brown powder which is hydrated iron oxide commonly known as rust. It is a chemical change because we cannot get back iron from the rusted iron.