Question

Match the following :

List I		List II
A.	$SO _{2}$	(i)	Photochemical smog
B.	PAN	(ii)	Acid rain
C.	Smoke	(iii)	Stratospheric pollutant
D.	$CF_{2}CL_{2}$	(iv)	Particulate

The correct answer is

• A. (A)-(IV), (B)-(III), (C)-(I), (D)-(II)
• B. (A)-(III), (B)-(I), (C)-(IV), (D)-(II)
• C. (A)-(IV), (B)-(I), (C)-(III), (D)-(II)
• D. (A)-(II), (B)-(I), (C)-(IV), (D)-(III)

Answer 1

Answer: (D)

A-II, B-I, C-IV, D-III

(A) $S O _{2}$ Acid rain is caused by chemical reaction that begins when compounds like sulphur dioxide and nitrogen oxides are released into the air. There amount can rise very high into the atomosphere, where they mix and react with water, oxygen and other chemicals to form more acidic pollutants, known as acid rain.

(B) Photochemical smog is a mixture of air pollutants which have been chemically altered into further noxious compounds by exposure to sunlight. The main components of photochemical smog are nitrogen oxides, volatile organic compounds, tropospheric ozone and PAN (Peroxy Acetyl Nitrate).

(C) Smoke Smoke is a collectison of airborne solid and liquid particulates and gases emitted when a material undergoes combustion.

(D) $CF _{2} Cl _{2}$, $CFCs$ (chlorofluorocarbons), oxides of nitrogen are stratospheric pollutants.