The statues and monuments are mainly made from marble which is chemically calcium carbonate `(CaCO_(3))`.Acid rain has vapours of sulphuric acid dissolved in it. When it comes in contact with the various statues or monuments, the acid reacts chemically with calcium carbonate. As a result of the chemical reaction, the material of the statues are slowly eaten up. It is also called corrosion. Thus acid rain is a threat to our precious historical mounments and statues.
`CaCo_(3)+H_(2)SO_(4)rightarrowCaSO_(4)+H_(2)O+CO_(2)`
