Environmental Chemistry MCQs

By: Prof. Dr. Fazal Rehman | Last updated: May 23, 2025

1. : The transition layer above the stratosphere is known as
(A) Mesopause
(B) Ionosphere
(C) Tropopause
(D) Stratopause

2. : The region of the atmosphere near to the ground or earth surface (1-11 km) is called
(A) Troposphere
(B) Thermosphere
(C) Mesosphere
(D) Stratosphere

3. : Ozone absorbs UV radiation in the range
(A) 10-50 nm
(B) 220-330 nm
(C) 100-200 nm
(D) 50-100 nm

4. : The region of the atmosphere at an altitude of 85-90 km above the stratopause is called
(A) Thermosphere
(B) Mesosphere
(C) Troposphere
(D) Stratosphere

5. : Which species is/are present as major part of the mesosphere?
(A) O2, N2
(B) CO2
(C) Ozone
(D) O2, NO2

6. : Which statement is true with regard to humus?
(A) It is complex and decomposed organic component of soil
(B) It is dark brown in color
(C) It is source of mineral salt
(D) All of these

7. : Which is/are important components of the environment?
(A) Biotic components
(B) Abiotic components
(C) Energy components
(D) All of these

8. : Which is/are abiotic components of the environment?
(A) pH of water and soil
(B) Moisture and water levels
(C) Temperature & light intensity
(D) All of these

9. : Which statement is not related with environmental chemistry?
(A) Study of chemical processes occurring in the environment
(B) Impact of chemicals on the environment
(C) Use of green solvents to produce chemicals
(D) Remedial measures of pollutants

10. : Which is environmental pollutant?
(A) Urban runoff of pollutants washing
(B) Nutrients leaching from agricultural land into water
(C) Heavy metals contamination of land
(D) All of these

11. : Which biogeochemical cycle is not part of ecosystem?
(A) Carbon cycle
(B) Nitrogen cycle
(C) Oxygen cycle
(D) Potassium cycle

12. : Which substance is most abundant of all parts of atmospheric air?
(A) N2
(B) O2
(C) Xe
(D) CO₂

13. : Which of the following is the study of sources, reactions, effects of chemical species in atmosphere?
(A) Environmental chemistry
(B) Industrial ecology
(C) Green chemistry
(D) Biology

14. : Which procedures involved in pollutants analysis?
(A) Atomic absorption spectrophotometry
(B) LCMS
(C) GC-MS
(D) All of these

15. : Which statement is not true with respect to hydrolytic cycle?
(A) Water covers about 71% of the earth’s surface
(B) Water covers about 83% of the earth’s surface
(C) It is the major constituent of the lithosphere
(D) It is essential requirement of all the organisms

16. : Dispersion of microscopic particles in a gaseous medium is called aerosols. Which is/are aerosol?
(A) Mist
(B) Cloud
(C) Smoke
(D) All of these

17. : Which is an important aspect of industrial ecology?
(A) Minimizing liquid waste
(B) Minimizing air emissions
(C) Designing for energy efficiency
(D) All of these

18. : Which statement is not true with regard to contaminant?
(A) It is undesirable substance
(B) It is not toxic to environment
(C) It is introduced by anthropogenic activity
(D) It is physical or chemical agent

19. : Which statement is not true with regard to pollutant?
(A) It is physical or chemical agent
(B) It is desirable substance
(C) It is introduced by anthropogenic activity
(D) It is toxic to environment

20. : Which statement is true with regard to effluent?
(A) It is waste liquid discharged from industry
(B) It is untreated sewage liquid
(C) It is a treated sewage liquid
(D) All of these

21. : Which is/are biotic components of the environment?
(A) Microorganisms
(B) Plants & Animals
(C) Human beings
(D) All of these

22. : The earth’s crust consisting of soil and rocks is called
(A) Atmosphere
(B) Hydrosphere
(C) Lithosphere
(D) Biosphere

23. : Which gases occur as in trace amount in the atmosphere?
(A) Ne, He, Kr
(B) H2, SO2, O2
(C) CH4, N2O, CO
(D) All of these

24. : Which statement is true with regard to atmosphere?
(A) The atmosphere protects us from the harmful radiations
(B) It provides carbon dioxide for photosynthesis
(C) It provides life sustaining oxygen
(D) All of these

25. : Which statement is not true with regard to atmosphere?
(A) It is the medium of the carriage of water from ocean to land
(B) It plays major role in maintaining the heat balance of earth
(C) It allows only radiations in the range of 300-2500 nm
(D) It screens the UV radiation of above 300

26. : Which is component of the ecosystem?
(A) Inorganic substances
(B) Animals and plants only
(C) Organic substances
(D) All of these

27. : Which energy is trapped by the autotrophic organisms?
(A) Radiant energy
(B) Electrical energy
(C) Mechanical energy
(D) Vibrational energy

28. : In biological ecosystem, which substance is used by organisms?
(A) Water
(B) Minerals
(C) Sunlight
(D) All of these

29. : The study of reduction of pollution using different principles is called
(A) Industrial ecology
(B) Green chemistry
(C) Environmental chemistry
(D) Biology

30. : Which abiotic component(s) vary with altitude?
(A) Air density
(B) Temperature
(C) Pressure
(D) All of these

31. : The temperature range of the troposphere is
(A) 15 to 0°C
(B) 15 to -56°C
(C) 15 to -20°C
(D) 15 to -10°C

32. : Which statement is not true regarding earth’s radiation balance?
(A) The earth absorbs about 34 % of solar
(B) The earth spectrum represents a peak of about 10,000 nm (IR)
(C) Light radiation of 483 nm (peak) are incident on earth’s surface
(D) The earth reflects and scatters back about 34% of solar flux (albedo)

33. : Select the physical characteristics of the atmosphere?
(A) Pressure and thickness
(B) Density and mass
(C) Temperature and speed
(D) All of these

34. : Which statements is not true regarding temperature inversion?
(A) Temperature of the atmosphere increases with altitude
(B) Cool air underlies warmer air at high altitude
(C) Temperature of the atmosphere decreases with altitude
(D) It may result from the invasion of sea by a cooler breeze

35. : Which of the following is the cause of environmental pollution?
(A) Transportation
(B) Agricultural activities
(C) Industries
(D) All of these

36. : Which species is/are present as major part of the troposphere?
(A) H₂O
(B) CO2
(C) O2, N2
(D) All of these

37. : The temperature of the troposphere falls off uniformly with increasing altitude. The cold layer (-56°C) at the top is known as
(A) Mesopause
(B) Tropopause
(C) Stratopause
(D) Ionosphere

38. : The region of the atmosphere above the ground or earth surface (11-50 km)/above the tropopause is called
(A) Stratosphere
(B) Troposphere
(C) Mesosphere
(D) Thermosphere

39. : Which species is/are present as major part of the stratosphere?
(A) O₂, N₂
(B) Ozone
(C) H₂O
(D) CO₂

40. : The temperature range of the stratosphere
(A) -56 to -2°C
(B) -56 to -10°C
(C) -56 to 0°C
(D) -56 to -30°C

41. : The temperature range of the mesosphere is
(A) 2 to -2°C
(B) -2 to 92°C
(C) -2 to 92°C
(D) 2 to -30°C

42. : The region of the atmosphere at an altitude of 85-500 km)/above the mesopause is called
(A) Stratosphere
(B) Troposphere
(C) Mesosphere
(D) Thermosphere

43. : Region of the atmosphere from 50-100 km is called
(A) Ionosphere
(B) Thermosphere
(C) Mesosphere
(D) Stratosphere

44. : Which species is/are present as major part of the ionosphere/thermosphere?
(A) O2, N2
(B) Ozone
(C) O₂+, NO+, O+
(D) CO2

45. : The component of the environment consisting of all surface and ground water resources is called
(A) Lithosphere
(B) Biosphere
(C) Atmosphere
(D) Hydrosphere

46. : The component of the environment encircling the earth’s surface where life exists is called
(A) Lithosphere
(B) Biosphere
(C) Atmosphere
(D) Hydrosphere

47. : The component of the environment consisting of a mixture of gases which acts as a protective blanket surrounding the earth is called
(A) Lithosphere
(B) Hydrosphere
(C) Biosphere
(D) Atmosphere

48. : The range of the atmosphere above the earth surface is
(A) It extends up to 100 km
(B) It extends up to 500 km
(C) It extends up to 200 km
(D) None of these

49. : The average concentration of CO2 (% by volume) in the atmosphere is
(A) 0.032
(B) 0.022
(C) 0.012
(D) None of these

50. : Which of the following is the science of the relationship of all the organisms to their environment?
(A) Biology
(B) Ecology
(C) Environmental chemistry
(D) Botany

51. : Which statement/s is not related with industrial ecology?
(A) Study of interactions between human activities and its environment
(B) Optimization of total industrial materials
(C) Industrial impacts on the environment
(D) Economic systems are viewed in isolation from their surroundings

52. : Which practice is involved in getting back nitrogen into atmosphere?
(A) Nitrification
(B) Denitrification
(C) Ammonification
(D) All of these

53. : Which is/are true regarding energy components of the environment?
(A) They are involved in abiotic components
(B) They are involved in biotic components
(C) They are involved in interaction between biotic and abiotic components
(D) All of these

54. : Which is/are components of the environment?
(A) Atmosphere
(B) Hydrosphere
(C) Lithosphere
(D) All of these

55. : The transition layer above the mesosphere is known as
(A) Stratopause
(B) Mesopause
(C) Tropopause
(D) Ionosphere