Why do we apply paint on iron articles?

Why do we apply paint of iron articles ?

(i) Solid calcium oxide was taken in a container and water was added slowly to it : (a) Write the observation . (b) Write the chemical formula of the product formed (ii) What happens when carbon dioxide gas is bubbled through lime water : (a) In small amount , (b) In excess? (iii) Why do you apply paint on iron articles ?

Why do we sweat ?

Why do we get rains?

Why do we group data?

Why do we group data?

Why do we feel thirsty?

Why do we paint wooden doors and windows?