1. Major contributor of green house effect is
1) CFC 2) O3 3) H2O 4) CO2
Ans: (4)
Explanation: CO2 - 50%, CFC - 17%, O3 - 8%, H2O - 2%.
2. PAN among the following is
Ans: (3)
Explanation: Peroxy acetyl Nitrate is 
3. Ozone layer is destroyed mainly due to-
1) Cl2 2) Cl• 3) ClO• 4) both 2 and 3
Ans: (2)
Explanation: One Cl• can destroy more than 1000 Ozone molecules.
4. Addition of phosphate fertilizers into water leads to
1) eutrophication 2) acid rain
3) green house effect 4) soil pollution
Ans: (1)
Explanation: due to over nutrition of lake.
5. Spraying of D.D.T. on crops produce
1) air pollution 2) soil pollution
3) water pollution 4) all the above
Ans: (4)
Explanation: non biodegradable DDT causes all the 3 types of pollution.
6. pH of acid rain water is
1) 7.4 2) 5.6 3) 7 4) 2.9
Ans: (2)
Explanation: pH of rain water is 5.6.
7. Gas released during Bhopal tragedy was
1) Methyl isocyanate 2) Methyl isocyanide
3) Methyl isocyanamide 4) Methyl iodocyanide
Ans: (1)
Explanation: Methyl isocyanate CH3NCO.
8. Which of the following contribute towards photochemical smog formation?
1) NO 2) hydrocarbons 3) both 1, 2 4) SO2
Ans: (3)
Explanation: Photochemical smog is formed due to NO, hydrocarbons.
9. Natural sources of air pollution are
1) volcanoic eruption 2) forest fire
3) both 1, 2 4) None
Ans: (3)
Explanation: forest fire and volcanoic eruption are natural causes of air pollution.
10. Presence of more Ozone in troposphere causes
1) Global warming 2) Ozone depletion
3) both 1, 2 4) none
Ans: (1)
Explanation: O3 is green house gas and traps infrared radiation.
11. The smog is essentially caused by the presence of
1) O2, O3 2) Oxides of sulphur, Nitrogen
3) O3, N2 4) O2, N2
Ans: (2)
Explanation: Smog is caused by Oxides of Sulphur (SO2, SO3) and Nitrogen (NO, NO2).
12. Wrong statement among the following is
1) Oxides of N, S causes acid rains
2) CFC's are responsible for Ozone depletion
3) Green house effect is responsible for global warming
4) Ozone layer does not permit infrared radiations from the sun to reach the earth
Ans: (4)
Explanation: Ozone layer does not permit harmful ultraviolet rays from the sun to reach the earth.
13. Green chemistry means such reactions which
1) the study of green plants in reducing pollution
2) reduce the use and production of hazardous chemicals
4) are related to the depletion of Ozone layer
Ans: (2)
Explanation: Green chemistry involves the use & production of hazardous chemicals.
14. Reaction between Methanamine and Phosgene produces
1) a gas released during Bhopal gas tragedy
2) a liquid causes smog
3) a gas causes anoxia
4) a solid causes minimata
Ans: (1)
Explanation: CH3NH2 + COCl2→ CH3NCO + 2 HCl
15. Clouds are formed in
1) Troposphere 2) Mesosphere
3) Stratosphere 4) Ionosphere
Ans: (3)
Explanation: Much water vapour and clouds are found in stratosphere.
16. Acid (s) present in acid rain is/are
1) HNO3 2) H2SO4 3) H2CO3 4) all the above
Ans: (4)
Explanation: HNO3, H2SO4, H2CO3 are formed in acid rain.
17. Ozone depletion causes
1) ageing of skin 2) cataract and skin cancer
3) killing of phytoplantons 4) all the above
Ans: (4)
Explanation: These causes are due to Ozone depletion.
18. Excessive Sulphate ( > 500 ppm) causes
1) Laxative effect 2) Blue baby syndrome
3) Cancer 4) Caissen bends
Ans: (1)
Explanation: Excess of sulphates (> 500 ppm) cause laxative effect.
19. Some countries maintain fluoride concentration of drinking water upto 1 ppm is due to
1) to prevent flurosis
2) not to become teeth yellow coloured
3) to protect teeth against decay
4) to prevent formation of bowed legs
Ans: (3)
Explanation: 1 ppm of fluorides protect teeth against decay.
20. Herbicide among the following
1) NaClO3 2) Na3AsO3 3) NaClO4 4) both 1, 2
Ans: (4)
Explanation: NaClO3, Na3AsO3 both are herbicides.
21. BOD values of municipal sewage is
1) 100 to 4,000 ppm 2) 10 to 400 ppm
3) 1 to 40 ppm 4) 10 to 4000 ppm
Ans: (1)
Explanation: Municipal sewage has BOD value from 100 to 4000 ppm.
22. Chlorine sinks in summer season are formed by
1) NO2 when reacts with Chlorine monoxide
2) CH4 when reacts with Chlorine monoxide
3) both 1, 2
4) NO2 when reacts with O3
Ans: (3)
Explanation: both 1, 2 are chlorine sinks.
23. Oxygen in air is about
1) 10 ppm 2) 2,00,000 ppm 3) 1,00,000 ppm 4) 40 ppm
Ans: (2)
Explanation: Oxygen in air is 2,00,000 ppm.
24. Mosquito repellant in a room is
1) Smog 2) Sink 3) Pollutant 4) Contaminant
Ans: (4)
Explanation: As it is newly enteres into environment causes environmental pollution.
25. The term "Acid rain" was first used by
1) Yves Chauvin 2) Robert H.Grubbs
3) Robert Angus 4) Richard R.Schrock
Ans: (3)
Explanation: Acid rain term was first used by ROBERT ANGUS.
