12th class (Fsc) Chemistry unit 16 MCQs
26. It was found that the majority of acids rains contain:
a. HNO3
b. H2CO3
c. H2SO3
d. All of given
27. Which one of the following substance cause acid rain?
a. Chlorofluorocarbons
b. SO2
c. Chlorofluorocarbons
d. None of these
28. Photochemical smoke is related to the pollution of:
a. Water
b. Soil
c. Air
d. Noise
29. The yellow color is photochemical smog is due to the presence of:
a. SO
b. NO
c. CO2
d. NO2
30. The combination of smoke and fog is called:
a. Smog
b. Primary pollutant
c. Coagulation
d. Secondary pollutant
31. Combustion of coal is the main source of:
a. Reducing smog
b. Acid rain
c. None of these
d. Oxidizing smog
32. Photochemical smog having higher concentration of O3 is:
a. Reducing smog
b. Smog
c. None of these
d. Oxidizing smog
33. The over all result of photochemical smog in afternoon is built up of:
a. Reducing agent
b. Neutralization agent
c. Activating agent
d. Oxidizing agent
34. The normal amount of overhead ozone is:
a. 400 DU
b. 300 DU
c. 450 DU
d. 350 DU
35. Which of the following is produced by reactions of ultraviolet light?
a. SO2
b. CO
c. NO2
d. O3
36. Amount of ozone is less in the region:
a. South polar region
b. North polar region
c. Antarctic region
d. Equator
37. The purpose of ozone layer is to protect earth from;
a. Visible rays
b. I.R rays
c. U.V rays
d. Cosmic rays
38. The troposphere where O3 layer exists in approximately at:
a. 15-35 km
b. 15-20 km
c. 5-35 km
d. 15-40 km
39. The troposphere is extent to an altitude of;
a. 5-15 km
b. 0-15 km
c. 15-35 km
d. 0-25 km
40. The temperature range of troposphere increases of altitude from:
a. -56 to -5oC
b. -56 to -12oC
c. -56 to -20oC
d. -56 to -2oC
41. The unit of ozone measurement is:
a. Pa
b. DU
c. Debye
d. mm Hg
42. which of the following compounds play affective role in removing O in stratosphere?
a. CI2
b. CFCI
c. O3
d. None of these
43. Hard water contains:
a. Chlorides of Na and K
b. Ca and Mg salts
c. Sulphates of al
d. Carbonates of Na and K
44. The substance which can directly kill the unwanted organisms are called:
a. Insecticides
b. Detergents
c. Pesticides
d. Herbicides
45. Which of the following substance control the growth of fungus on the plant?
a. Insecticides
b. Herbicides
c. Detergents
d. Fungicides
46. Which of the following substance kill undesired plants?
a. Insecticides
b. Herbicides
c. Fungicides
d. All of given
47. Which of the following substance is not pesticide?
a. Insecticides
b. Herbicides
c. Detergents
d. Fungicides
48. Detergents greatly affects:
a. Terrestrial life
b. Aquatic life
c. Plant’s life
d. Modren life
49. In human liver cancer is due to:
a. Carbon dioxide
b. Oxygen
c. Methane
d. Chloroform
50. Nutrient leach is due to:
a. Acidification of soil
b. Drying of soil
c. Neutralization of soil
d. Combustion of soil