Question

5 (b) Discuss the effects of acid rain on heritage buildings like Taj Mahal. State how the stone of Taj Mahal made of ${\mathrm{CaCO}}_3$ reacts with acid present in rain.

Answer 1

Part 1: Acid rain

• Acid rain causes damage to historical monuments and other buildings.
• Acid rain, or acid deposition, is a broad term that includes any form of precipitation with acidic components, such as sulfuric or nitric acid that fall to the ground from the atmosphere in wet or dry forms

Part 2: Effect of acid rain on Taj Mahal

• For example, the Taj Mahal is getting destroyed and is becoming yellow in color because of a reaction to acid rain.
• The city of Agra has many industries which emit the oxides of sulfur and nitrogen into the atmosphere.
• Marbles of Tajmahal contain calcium carbonate, this acid rain forms Calcium Sulphate which turns Taj Mahal's pristine white marble, making it yellowish
• Acid rain has the following reaction with the marble of calcium carbonate$\left({\mathrm{CaCO}}_3\right)$
• $\underset{\mathrm{Calcium}\mathrm{Carbonate}}{{\mathrm{CaCO}}_3\left(\mathrm{s}\right)}+\underset{\mathrm{Sulphuric}\mathrm{acid}}{{\mathrm{H}}_2{\mathrm{SO}}_4\left(\mathrm{aq}\right)}\to \underset{\mathrm{Calcium}\mathrm{Sulphate}}{{\mathrm{CaSO}}_4\left(\mathrm{s}\right)}+\underset{\mathrm{Water}}{{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)}+\underset{\mathrm{Carbon}\mathrm{dioxide}}{{\mathrm{CO}}_2\left(\mathrm{g}\right)}$
• The formation of calcium sulfate results in the corrosion of this beautiful moment