CAUSES OF ACID RAIN[CHEMISTRY OF SULPHUR]

DO YOU KNOW WHAT CAUSES ACID RAIN?

metals such as comites and mercaptans are involved in refining of crude oil..typical example of other sulphur derivatives are alkyl sulphates..
sulphur is very undesirable because of it corrosive effect on the distillation column..it also decreases the octane no of the fuel,it is associated with a lot of environmental pollutions and problems and also has bad odour..A small amount of sulphur in crude oil makes it undesirable but at the same time a little amount is necessary about 0.2---0.7
is present in lubricating oil,brake oil,engine oil,power stering oil..

thus sulphur can be discharged into the atmosphere through the car exhaust engines.the discharged sulphur is taken up by water in the atmosphere as vapour and are released to the earth during rainfall..this is what is known as ACID RAIN.. whose ultimate demerit is to cause cancer and depletion of hormone layer..

WHEN RAIN WATER IS IN EQUILIBRIUM WITH ATM Carbon[iv] oxide,IT WILL FORM A SLIGHTLY ACIDIC WATER

H2O + CO2---------H2CO3

WHEN THE PH VALUE IS LESS THAN 5.6,IT IS DESCRIBED AS ACID RAIN..ACIDIC GASEOUS POLLUTANT SUCH AS Nitrogen oxide AND sulphur dioxide ARE RESPONSIBLE

2SO2 + O2--------2SO3
SO3 + H20---------H2SO4

Nitrogen dioxide FROM AUTOMOBILE EXHAUST FIRST ABSORBS SUNLIGHT AND BREAKDOWN TO Nitric oxide AND REACTIVE OXYGEN ATOM

NO2----------NO + O

OXYGEN THEN REACTS WITH OTHER COMPONENTS OF AUTOMOBILE EXHAUST [UNBURNT HYDROCARBON] AND THOSE OF ATMOSPHERE [OXYGEN AND WATER VAPOUR] TO FORM SERIES OF COMPLEX REACTION TO PRODUCE A VARIETY OF TOXIC ELEMENTS SUCH AS PEROXYACYLNITRATE.