Dear candidate

When the pH of the rain is less than 5 then it is called acid rain is due to the poisonous gasses like SO2 and NOx released from the industries due and increased vehicle use and on the road into the atmosphere which leads pollution these gasses travel through air and Combine woth oxygen and other chemicals in the water leads to the formation of sulfuric and nitric acids and these react with water of rain makes the rain acidic. SO2 and NOX are the compounds which are majorly responsible for  acid rain. The yellowish colour of marbel of Taj Mahal was due to this rain as area around taj mahal was highly polluted and there are lot of effects like skin diseases,  pollution of water and air and harms aqatic and wild life, leaching of aluminium from clay many others.

Hope this Information is helpful