This document provides a practice test for environmental chemistry. It contains 78 multiple choice questions covering various topics related to environmental chemistry including the greenhouse effect, ozone layer depletion, air pollution, water pollution, and acid rain. The questions assess understanding of concepts, processes, and impacts related to these forms of environmental pollution. Answers to the questions are not provided. Contact information is given to obtain additional practice tests via WhatsApp.

1. Malik Xufyan
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PPSC CHEMISTRY CLASS
Test Session
Chapter: Environmental Chemistrty
Test No. 14
For more WhatsApp # 0313-7355727
Topics:
1- Concept of Environmental Chemistry
2- Environmental Pollution
3- Green House Effect
4- Air Pollution
5- Water Pollution
6. Chemical Toxicology
Kindly choose the correct answer:
1)What is the source of lead compounds?
(a) aerosol sprays foams
(b) exhaust fumes of motor vehicles
(c) incomplete burning of wood
(d) none of above
2)Depletion of the ozone layer is caused due to
(a) Ferrocene
(b) Fullerenes
(c) Freons
(d) Polyhalogens
3)The temperature of the outer mesosphere is
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(a) 93 °C
(b) −93 °C
(c) 5 °C
(d) −5 °C
4) Good ozone is found in the
(a) stratosphere
(b) ionosphere
(c) troposphere
(d) mesosphere
5) This is not the consequence of ozone layer depletion
(a) malignant melanoma – skin cancer type
(b) increased ultraviolet radiations
(c) tides
(d) cyanobacteria are sensitive to UV rays and would be affected by its increase
6) Greenhouses gases causing a rise of 3℃ rise in the overall global temperature in the
past century are CFCs. The CFC used in refrigerators is
(a) Ammonia
(b) Freon
(c) Methane
(d) carbon dioxide
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7) Main cause of ozone holes and its depletion is
(a) propellants
(b) foam-blowing agents
(c) halocarbon refrigerants
(d) all of these
8) Ozone can be destroyed by the following free radical(s)
(a) chlorine radical (Cl)
(b) hydroxyl radicals (OH)
(c) nitric oxide radical (NO)
(d) all of these
9) Following form(s) of oxygen is/are involved in ozone-oxygen cycle
(a) triatomic oxygen (O3)
(b) diatomic oxygen (O2)
(c) atomic oxygen (O)
(d) all of these
10) Ozone-depleting substance chiefly utilized in
(I) chimneys
(II) all of the human activities
(III) burning fossil fuels
(IV) cooling and refrigeration applications and in the manufacturer of foam products
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(a) All
(b) Only IV
(c) Only I, II and III
(d) Only I and II
11) Montreal protocol is related to the
(a) food security
(b) global warming
(c) sustainable development
(d) ozone layer depletion
12) This is a major risk linked with extreme ultraviolet rays through the atmosphere as
a result of ozone layer depletion
(a) neurological disorder
(b) digestive system gets damaged
(c) increased liver cancer
(d) increased skin cancer
13) UV rays is higher in summer as
(a) during summer, ozone is more in the atmosphere
(b) sun is busy in summer specially
(c) sun is closer to planet earth so UV rays have a shorter distance to travel and reach us
(d) none of the above
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14) Find the incorrect statement
(a) BOD value of clean water is less than 5 ppm
(b) Drinking water pH should be between 5.5-9.5
(c) carbon, sulphur and nitrogen oxides are the most widespread air pollutants
(d) dissolved oxygen concentration below 5 ppm is ideal for the growth of fish
15) Photochemical smog normally does not contain
(a) Chlorofluorocarbons
(b) Peroxyacetyl nitrate
(c) Ozone
(d) Acrolein
16) Find the secondary pollutant among these
(a) PAN
(b) N2O
(c) SO2
(d) CO2
17) The reaction responsible for the radiant energy of the Sun is
(a) nuclear fission
(b) nuclear fusion
(c) chemical reaction
(d) combustion
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18) Alum’s capacity to purify water is due to
(a) softens hard water
(b) pathogenic bacteria get destroyed
(c) impurities’ coagulation
(d) it improves taste
19) The atmosphere is divided into how many layers?
(a) two
(b) three
(c) four
(d) five
20)How much higher can be the temperature inside a greenhouse as compared to the
outside?
(a) 20 °C higher
(b) 10 °C to 15 °C higher
(c) 5 °C higher
(d) 25 °C higher
21)The coldest region of the atmosphere
(a) Troposphere
(b) Thermosphere
(c) Stratosphere
(d) Mesosphere
22)Which of the oxide of nitrogen is not a common pollutant?
(a) N2O5
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(b) N2O
(c) NO
(d) NO2
23) The compound essential for the process of photosynthesis has this element
(a) Ca
(b) Ba
(c) Fe
(d) Mg
24) Minimum temperature of the troposphere is
(a) 17 °C
(b) −55 °C
(c) −5 °C
(d) 1800 °C
25) In the air, N2 and O2 occur naturally but they do not react to form oxides of nitrogen
because
(a) oxides of nitrogen are unstable
(b) catalyst is required for the reaction
(c) the reaction is endothermic
(d) N2 and O2 do not react with each other
26)Which of the following have an impact on brain development in human beings
especially among children?
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(a) chlorofluorocarbons (CFCs)
(b) methane
(c) carbon monoxide
(d) lead compounds
27) Which of the following is a powerful irritant which can aggravate the symptoms of
people who suffer from respiratory disorders?
(a) sulphur dioxide
(b) carbon monoxide
(c) carbon dioxide
(d) oxides of nitrogen
28) Which two main gases are produced when you burn a piece of wood?
(a) oxygen and nitrogen
(b) carbon dioxide and oxygen
(c) carbon dioxide and carbon monoxide
(d) carbon dioxide and nitrogen
29)The occurrence of weather is in
(a) troposphere
(b) stratosphere
(c) mesosphere
(d) thermosphere
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30) Which of the following is true about sulfur dioxide?
(a) it is colorless
(b) it is odourless
(c) it is not an air pollutant
(d) it does not cause breathing difficulties
31) Height of troposphere is
(a) 10 Km
(b) 12 Km
(c) 50 Km
(d) 80 Km
32) Which of the following has the lowest percentage in the air?
(a) krypton
(b) argon
(c) hydrogen
(d) helium
33) Height of stratosphere is
(a) 0-12 Km
(b) 12-50 Km
(c) 50-80 Km
(d) above 80 Km
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34) Ozone formation and destruction are powered by
(a) oxygen gas
(b) atomic oxygen
(c) ultraviolet radiation
(d) chlorine gas
35) Which of the following causes headache and dizziness and can even cause death if
inhaled for a long time?
(a) sulphur dioxide
(b) carbon dioxide
(c) nitrogen dioxide
(d) carbon monoxide
36) Which of the following is an excellent heat absorber and causes global warming?
(a) chlorofluorocarbons (CFCs)
(b) methane
(c) carbon monoxide
(d) lead compounds
37) Which One of the Following Is Not a Greenhouse Gas?
(a) Methane
(b) Hydrogen
(c) Nitrous oxide
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(d) Ozone
38) Which of the Following Have Higher Energy Levels and Shorter Wavelengths?
(a) Infrared radiation
(b) Ultraviolet radiation
(c) Beta radiation
(d) Alpha radiation
39) Normal Greenhouse Effect Is Important for the Sustenance of Life on Earth as it
Has Increased the Earth’s Surface Temperature By
(a) 15 ℃
(b) 50 ℃
(c) – 18 ℃
(d) 33 ℃
40) Infrared Radiations Have ----------------Wavelength?
(a) Shorter
(b) Infinite
(c) Longer
(d) Zero
41) Which of the Following Greenhouse Gases Is Present in Very High Quantities?
(a) Carbon dioxide
(b) Ethane
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(c) Propane
(d) Methane
42) Gas Molecules That Absorb Thermal Infrared Radiation and Are Present in Large
Quantity to Alter the Climate System Is Known As
(a) Greenhouse gases
(b) Beta radiations
(c) Alpha radiations
(d) Ozone gases
43) Burning of Fossil Fuels Results In
(a) Increased oxygen level
(b) Decreases greenhouse gases
(c) Increased greenhouse gases
(d) Increased ethane level
44) the Most Potent Greenhouse Gas in Terms of Efficiency Is
(a) N2O
(b) C2O
(c) CFC
(d) CH4
45) Which One of the Following Is Incorrect About the Greenhouse Effect?
(a) Life on earth is possible due to greenhouse effect
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(b) Greenhouse effect is a natural process that maintains earth’s temperature
(c) More is the emission of greenhouse gases, more is the temperature of the earth’s
atmosphere
(d) Increased emission of greenhouse gases is a natural process
46) Which is Not Naturally Occurring Greenhouse Gas?
(a) Nitrous oxide
(b) Methane
(c) Carbon dioxide
(d) Ethane
47) Which is Not True for the Relative Contribution of Various Greenhouse Gases to
Total Global Warming?
(a) CFCs – 14%
(b) Carbon dioxide – 60%
(c) N2O – 12%
(d) Methane – 20%
48) the GWP is Dependent on Which of the Following Factors?
a) Absorption capability of InfraRed radiations
b) Atmospheric life-time
c) Range of Infrared wavelengths it can absorb
d) All of the above
49) Which of the Following Greenhouse Gases Has the Highest Atmospheric Lifetime?
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a) CFC
b) Nitrous oxide
c) Methane
d) Carbon tetrafluoride
50) Which of the Following Has the Highest Radiative Efficiency?
a) Sulphur hexafluoride
b) Carbon tetrachloride
c) CFC
d) PFTBA
51) Which Among the Following Compounds Have the Highest Gwp?
a) Nitrous oxide
b) Sulphur hexafluoride
c) Water vapour
d) CFC
52) Anthropogenic Sources of Carbon Dioxide Are 20 Times More Than Natural
Carbon Dioxide Sources.
a) True
b) False
53) Why Is There an Extreme Difference in Temperatures at Day and Night in Deserts?
a) Carbon dioxide is present in low concentrations in desert regions, and thus heat escapes
easily
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b) Sand has high heat conduction properties
c) There’s lack of moisture leads to escape of heat
d) All of the above
54) Which is a sink for carbon?
a) Saline water bodies
b) Old oil fields
c) Wetlands
d) All of the above
55) Volcanic Eruptions Also Contribute to the Global Greenhouse Effect.
a) True
b) False
56) Which of the following is biodegradable pollutant
(a) Sewage
(b) Plastic
(c) Polythene
(d) DDT
57) B.O.D. test or biological oxygen demand test is made for measuring
(a) Air pollution
(b)Water pollution
(c) Noise pollution
(d) Soil pollution
58) Water pollution
(a) Increases oxygenation
(b) Decreases turbidity
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(c) Increases turbidity and deoxygenation
(d) Increases photosynthesis
59) Biological Oxygen Demand (BOD) is a measure of
(a) Industrial wastes poured into water bodies
(b) Extent to which water is polluted with organic compounds
(c) Amount of carbon monoxide inseparably combined with haemoglobin
(d) Amount of oxygen needed by green plants during night
60) Which of the following is a water polluting factor
(a) Smoke
(b) Industrial waste
(c) Detergent
(d) Ammonia
61) Which of the following is a main factor of water pollution
(a) Commercial production
(b) Windmill
(c) Smoke and ammonia
(d) Detergents
62) Who was the first to recognise the problem of water pollution ?
(a) Airstotle
(b) Theophrastus
(c) Hippocrates
(d) Thales
63) Thermal pollution of water bodies is due to
(a) Discharge of heat (hot water) from power plants
(b) Discharge of chemicals from industries
(c) Discharge of waste from mining
(d) Discharges of agricultural run off
64) Water pollution can be stopped best by
(a) Treating effluents to remove injurious chemicals
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(b) Rearing more fishes
(c) Cultivating useful water plants
(d) Spraying with DDT
65) The main cause of water pollution is
(a) Soap
(b) Industrial effluents
(c) Smoke
(d) Ammonia
66) Minamata disease is a pollution related disease results from
(a) Oil spills into sea
(b) Accumulation of arsenic into atmosphere
(c) Release of industrial waste mercury into fishing water
(d) Release human organic waste into drinking water
67) The excessive discharge of fertilizers into water bodies results in
(a) Growth of fish
(b) Death of hydrophytes
(c) Eutrophication
(d) Silt
68) Foul smell in the water of tanks, ponds etc. is due to
(a) Anaerobiosis
(b) Aerobiosis
(c) Biological magnification
(d) Psammophytes
69)Which of the following does not occur when the sewage is discharged into water
(a) Increase in O2
(b) Cyanophycean blooms occur
(c) Depletion of O2 layers
(d) Eutrophication
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70) Which of the following metal is a water pollutant and causes sterility in human
being
(a) As
(b) Mn
(c) Mg
(d) Hg
71) Which regions of seas/oceans are the most polluted ?
(a) Estuarine
(b) Coastal
(c) Sea depths
(d) Coral reefs
72) The main contributors of acid rain are
(a) sulphur oxides and carbon oxides
(b) nitrogen oxides and sulphur oxides
(c) carbon dioxide and carbon monoxide
(d) nitrogen oxides and carbon oxides
73) Who coined the term acid rain?
(a) Christ Ralph
(b) Elmer Joseph Clark
(c) Ernest Flower
(d) Robert Angus Smith
74) The main cause of acid rain is
(a) soil pollution
(b) water pollution
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(c) air pollution
(d) all of the above
75) Sulphur dioxide is produced by
(a) nuclear power plant
(b) coal power plants
(c) hydroelectric power plants
(d) all of the above
76) Acid rain reacts with marble and limestone to form
(a) calcium carbonate
(b) calcium hydroxide
(c) calcium sulphate
(d) none of the above
77) Acid rain causes damage to
(a) big sculptures and marble constructions
(b) flora and fauna
(c) growth of trees
(d) all of the above
78) The pH of normal rainwater is
(a) basic
(b) acidic
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(c) alkaline
(d) neutral
79) The pH below which the precipitation is regarded as acid rain is
(a) 6
(b) 7
(c) 5.6
(d) 7.3
80) Among the following, the only secondary pollutant is:
(a) Sulphur tetraoxide
(b) Sulphur dioxide
(c) Ozone
(d) Sulphur tetraoxide
81) Which of the following groups of plants can be used as indicators of SO pollution of
air?
(a) Epiphytic lichens
(b) Ferns
(c) Liver worts
(d) Horn worts
82) Which of the following on inhalation dissolved in the blood hemoglobin more
rapidly than oxygen?
(a) Sulphur dioxide
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(b) Carbon mono-oxide
(c) Ozone
(d) Nitrous oxide
83) Smog is:
(a) A natural phenomenon
(b) A combination of smoke and fog
(c) Is colourless
(d) All of the above
84) The major photochemical oxidant is:
(a) Ozone
(b) Hydrogen peroxide
(c) Nitrogen oxides
(d) Peroxyl Acetyl Nitrate (PAN)
85) Which of the following are likely to be present in photochemical smog?
(a) Sulphur dioxide
(b) Photochemical oxidants
(c) Chlorofluorocarbon
(d) Smog
86) Air pollution from automobiles can be controlled by fitting:
(a) Cyclone separato
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(b) Electrostatic precipitator
(c) Catalytic converter
(d) Wet scrubber
87) Excess fluoride in drinking water is likely to cause:
(a) Blue baby syndrome
(b) Fluorosis
(c) Change in taste and odour
(d) Intestinal irritation
88) Which of the following is a non-point source of water pollution?
(a) Factories
(b) Sewage treatment plants
(c) Urban and suburban lands
(d) All of the above
89) Which of the following is not a marine pollutant?
(a) Oil
(b) Plastics
(c) Dissolved oxygen
(d) All of the above
90) High level radioactive waste can be managed in which of the following ways?
(a) Open dumping
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(b) Composting
(c) Incineration
(d) Dumping in sealed containers
91) Which of the following is a biodegradable organic chemical/substance?
(a) Plastics
(b) Oils
(c) Pesticides
(d) Garbage
92) DDT was banned in:
(a) 1961
(b) 1972
(c) 1982
(d) 1943
93) DDT pollutant concentration at initial level is:
(a) 2 ppm
(b) 0.2 ppm
(c) 0.04 ppm
(d) 1 ppm
94) The 99% of the Earth’s atmosphere consists of
(a) Oxygen
(b) Nitrogen
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(c) Oxygen and Nitrogen
(d) Nitrogen and Water
95) In the lower layers of atmosphere, what range of wavelengths of light is
predominant?
a) Less than 100 nm
b) Greater than 300 nm
c) Between 100-300 nm
d) All wavelengths are equally present
96) The build-up of a toxic chemical as it goes up a food chain is:
a) Biomagnification only
b) Bioaccumulation only
c) Both biomagnification and bioaccumulation
d) None of these
97) What happens when phosphorus, nitrates, and detergents in water lead to an
acceleration in the growth of algae?
a) Extinction
b) Eutrophication
c) Increase in the number of fishes
d) Increase in the number of aquatic plants
98) Which of the following is the test to the determine amount of oxygen needed to
oxidize all pollution materials?
a) Biological Oxygen Demand
b) Chemical Oxygen Demand
c) Botanical Oxygen Demand
d) Physical Oxygen Demand
99) Which of the following is not used as a standard test battery for measuring bio-
accumulation?
a) Algae
b) Zooplanktons
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c) Fish
d) Birds
100) The amount of toxicants and chemicals that accumulates in the ecosystem after the
transfer is called as ________
a) Bio accumulated
b) Bio-polluted
c) Bio hazard
d) Bio degradation
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