Question

Question 14.6 What is smog? How is classical smog different from photochemical smog?

Class XI Environmental Chemistry Page 413

Answer 1

The word ' smog ' is the combination of " smoke " and " fog " . it is the most common example of air pollution that occurs in many cities throughout the world . mainly , there are two types of smog :

1. classical smog : it occurs in cool humid climate . it is a mixture of smoke , fog and SO2 . chemically, it is a reducing mixture . so, it is called reducing smog .

2. photochemical smog : it occurs in warm, dry and sunny climate . the main components of it is ozone , acrolein , peroxyacylnitrates . and these are produced by the action of sunlight on unsaturated hydrocarbons and nitrogen oxides are produced by automobiles and factories . chemically , it is oxidising smog because it has high concentration of oxidizing agents .