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Environmental Chemistry

134 Questions Start JEE Mains Test
All Exams JEE Mains JEE Advanced TS-EAMCET AP-EAPCET BITSAT
2022 Q51 JEE Mains MCQ
14 Mar 2026

Given below are two statements:

Statement I : In polluted water values of both dissolved oxygen and $\mathrm{BOD}$ are very low.

Statement II : Eutrophication results in decrease in the amount of dissolved oxygen.

In the light of the above statements, choose the most appropriate answer from the options given below :

A.
Both Statement I and Statement II are true
B.
Both Statement I and Statement II are false
C.
Statement I is true but Statement II is false
D.
Statement I is false but Statement II is true
2022 Q52 JEE Mains MCQ
14 Mar 2026

Given below are two statements:

Statement I : The non bio-degradable fly ash and slag from steel industry can be used by cement industry.

Statement II : The fuel obtained from plastic waste is lead free.

In the light of the above statements, choose the most appropriate answer from the options given below :

A.
Both Statement I and Statement II are correct
B.
Both Statement I and Statement II are incorrect
C.
Statement I is correct but Statement II is incorrect
D.
Statement I is incorrect but Statement II is correct
2022 Q53 JEE Mains MCQ
14 Mar 2026

Match List I with List II.

List I

Pollutant		 List II

Disease/sickness
(A) Sulphate (>500 ppm) (I) Methemoglobinemia
(B) Nitrate (>50 ppm) (II) Brown mottling of teeth
(C) Lead (>50 ppb) (III) Laxative effect
(D) Fluoride (>2 ppm) (IV) Kidney damage

Choose the correct answer from the options given below :

A.
A-IV, B-I, C-II, D-III
B.
A-III, B-I, C-IV, D-II
C.
A-II, B-IV, C-I, D-III
D.
A-II, B-IV, C-III, D-I
2022 Q54 JEE Mains MCQ
14 Mar 2026

Match List I with List II.

List I

Pollutant		 List II

Source
(A) Microorganisms (I) Strip mining
(B) Plant nutrients (II) Domestic sewage
(C) Toxic heavy metals (III) Chemical fertilizer
(D) Sediment (IV) Chemical factory

Choose the correct answer from the options given below :

A.
A-II, B-III, C-IV, D-I
B.
A-II, B-I, C-IV D-III
C.
A-I, B-IV, C-II, D-III
D.
A-I, B-IV, C-III, D-II
2022 Q55 JEE Mains MCQ
14 Mar 2026

The photochemical smog does not generally contain :

A.
NO
B.
NO2
C.
SO2
D.
HCHO
2022 Q56 JEE Mains MCQ
14 Mar 2026

The acid that is believed to be mainly responsible for the damage of Taj Mahal is :

A.
sulfuric acid.
B.
hydrofluoric acid.
C.
phosphoric acid.
D.
hydrochloric acid.
2022 Q57 JEE Mains MCQ
14 Mar 2026

Correct statement about photo-chemical smog is :

A.
It occurs in humid climate.
B.
It is a mixture of smoke, fog and SO2.
C.
It is reducing smog.
D.
It results from reaction of unsaturated hydrocarbons.
2022 Q58 JEE Mains MCQ
14 Mar 2026

On the surface of polar stratospheric clouds, hydrolysis of chlorine nitrite gives A and B while its reaction with its reaction with HCl produces B and C. A, B and C are, respectively :

A.
HOCl, HNO3, Cl2
B.
Cl2, HNO3, HOCl
C.
HClO2, HNO2, HOCl
D.
HOCl, HNO2, Cl2O
2022 Q59 JEE Mains MCQ
14 Mar 2026

Given below are two Statements:

Statement I : Classical smog occurs in cool humid climate. It is a reducing mixture of smoke, fog and sulphur dioxide.

Statement II : Photochemical smog has components, ozone, nitric oxide, acrolein, formaldehyde, PAN etc.

In the light of the above statements, choose the most appropriate answer from the options given below.

A.
Both Statement I and Statement II are correct.
B.
Both Statement I and Statement II are incorrect.
C.
Statement I is correct but Statement II is incorrect.
D.
Statement I is incorrect but Statement II is correct.
2022 Q60 JEE Mains MCQ
14 Mar 2026

The measured BOD values for four different water samples (A-D) are as follows: A = 3 ppm; B = 18 ppm; C = 21 ppm; D = 4 ppm. The water samples which can be called as highly polluted with organic wastes, are :

A.
A and B
B.
A and D
C.
B and C
D.
B and D
2022 Q61 JEE Mains MCQ
14 Mar 2026

Polar stratospheric clouds facilitate the formation of :

A.
ClONO2
B.
HOCl
C.
ClO
D.
CH4
2022 Q62 JEE Mains MCQ
14 Mar 2026

Given below are two statements : One is labelled as Assertion A and the other is labelled as Reason R.

Assertion A : Polluted water may have a value of BOD of the order of 17 ppm.

Reason R : BOD is a measure of oxygen required to oxidise both the bio-degradable an non-biodegradable organic material in water.

In the light of the above statements, choose the most appropriate answer from the options given below.

A.
Both A and R are correct and R is the correct explanation of A.
B.
Both A and R are correct but R is NOT the correct explanation of A.
C.
A is correct but R is not correct.
D.
A is not correct but R is correct.
2022 Q63 JEE Mains MCQ
14 Mar 2026

The eutrophication of water body results in :

A.
loss of Biodiversity.
B.
breakdown of organic matter.
C.
increase in biodiversity.
D.
decrease in BOD.
2022 Q64 JEE Mains MCQ
14 Mar 2026

Some gases are responsible for heating of atmosphere (green house effect). Identify from the following the gaseous species which does not cause it.

A.
CH4
B.
O3
C.
H2O
D.
N2
2022 Q65 BITSAT MCQ
11 Jun 2026

Match the species in Column I with their types in Column II.

Column I Column II
A. DDT 1. Photochemical smog
B. NaClO$_3$ 2. Disinfectant
C. Cl$_2$ 3. Herbicides
D. PAN 4. Pesticides

A.
A $\to$ 4, B $\to$ 3, C $\to$ 2, D $\to$ 1
B.
A $\to$ 1, B $\to$ 2, C $\to$ 3, D $\to$ 4
C.
A $\to$ 2, B $\to$ 3, C $\to$ 1, D $\to$ 4
D.
A $\to$ 3, B $\to$ 1, C $\to$ 2, D $\to$ 4
2021 Q66 JEE Mains MCQ
14 Mar 2026
Water sample is called cleanest on the basis of which one of the BOD values given below :
A.
11 ppm
B.
15 ppm
C.
3 ppm
D.
21 ppm
2021 Q67 JEE Mains MCQ
14 Mar 2026
The deposition of X and Y on ground surfaces is referred as wet and dry depositions, respectively. X and Y are :
A.
X = Ammonium salts, Y = CO2
B.
X = SO2, Y = Ammonium salts
C.
X = Ammonium salts, Y = SO2
D.
X = CO2, Y = SO2
2021 Q68 JEE Mains MCQ
14 Mar 2026
BOD values (in ppm) for clean water (A) and polluted water (B) are expected respectively :
A.
A > 50, B < 27
B.
A > 25, B < 17
C.
A < 5, B > 17
D.
A > 15, B > 47
2021 Q69 JEE Mains MCQ
14 Mar 2026
In stratosphere most of the ozone formation is assisted by :
A.
cosmic rays
B.
$\gamma$-rays
C.
ultraviolet radiation
D.
visible radiations
2021 Q70 JEE Mains MCQ
14 Mar 2026
Which one of the following is used to remove most of plutonium from spent nuclear fuel?
A.
ClF3
B.
O2F2
C.
I2O5
D.
BrO3
2021 Q71 JEE Mains MCQ
14 Mar 2026
The gas 'A' is having very low reactivity reaches to stratosphere. It is non-toxic and non-flammable but dissociated by UV-radiations in stratosphere. The intermediates formed initially from the gas 'A' are :
A.
$Cl\mathop O\limits^ \bullet + \mathop C\limits^ \bullet {F_2}Cl$
B.
$Cl\mathop O\limits^ \bullet + C\mathop {{H_3}}\limits^ \bullet $
C.
$\mathop C\limits^ \bullet {H_3} + C\mathop {{F_2}}\limits^ \bullet Cl$
D.
$\mathop C\limits^ \bullet l + C\mathop {{F_2}}\limits^ \bullet Cl$
2021 Q72 JEE Mains MCQ
14 Mar 2026
Given below are two statements : one is labelled as Assertion (A) and the other is labelled as Reason (R).

Assertion (A) : Photochemical smog causes cracking of rubber.

Reason (R) : Presence of ozone, nitric oxide, acrolein, formaldehyde and peroxyacetyl nitrate in photochemical smog makes it oxidizing.

Choose the most appropriate answer from the options given below :
A.
Both (A) and (R) are true but (R) is not the true explanation of (A)
B.
(A) is false but (R) is true.
C.
(A) is true but (R) is false.
D.
Both (A) and (R) are true and (R) is the true explanation of (A)
2021 Q73 JEE Mains MCQ
14 Mar 2026
The conversion of hydroxyapatite occurs due to presence of F$-$ ions in water. The correct formula of hydroxyapatite is :
A.
[3Ca3(PO4)2 . Ca(OH)2]
B.
[3Ca(OH)2 . CaF2]
C.
[Ca3(PO4)2 . CaF2]
D.
[3Ca3(PO4)2 . CaF2]
2021 Q74 JEE Mains MCQ
14 Mar 2026
Which one of the following statements is NOT correct?
A.
Eutrophication indicates that water body is polluted
B.
The dissolved oxygen concentration below 6 ppm inhibits fish growth
C.
Eutrophication leads to increase in the oxygen level in water
D.
Eutrophication leads to anaerobic conditions
2021 Q75 JEE Mains MCQ
14 Mar 2026
Given below are two statements :

Statement I : Chlorofluoro breakdown by radiation in the visible energy region and release chlorine gas in the atmosphere which then reacts with stratospheric ozone.

Statement II : Atmospheric ozone reacts with nitric oxide to give nitrogen and oxygen gases, which add to the atmosphere.

For the above statements choose the correct answer from the options given below :
A.
Statement I is incorrect but Statement II is true
B.
Both Statement I and II are false
C.
Statement I is correct but Statement II is false
D.
Both Statement I and II are correct
2021 Q76 JEE Mains MCQ
14 Mar 2026
Which one of the following gases is reported to retard photosynthesis?
A.
CO
B.
CFCs
C.
CO2
D.
NO2
2021 Q77 JEE Mains MCQ
14 Mar 2026
Given below are two statements :

Statement I : Non-biodegradable wastes are generated by the thermal power plants.

Statement II : Bio-degradable detergents leads to eutrophication.

In the light of the above statements, choose the most appropriate answer from the options given below :
A.
Statement I is false but statement II is true.
B.
Both statement I and statement II are true.
C.
Both statement I and statement II are false.
D.
Statement I is true but statement is false.
2021 Q78 JEE Mains MCQ
14 Mar 2026
The statements that are TRUE :

(A) Methane leads to both global warming and photochemical smog

(B) Methane is generated from paddy fields

(C) Methane is a stronger global warming gas than CO2

(D) Methane is a part of reducing smog

Choose the most appropriate answer from the options given below :
A.
(A), (B), (C) only
B.
(A) and (B) only
C.
(B), (C), (D) only
D.
(A), (B), (D) only
2021 Q79 JEE Mains MCQ
14 Mar 2026
Which of the following statement(s) is (are) incorrect reason for eutrophication?

(A) excess usage of fertilisers

(B) excess usage of detergents

(C) dense plant population in water bodies

(D) lack of nutrients in water bodies that prevent plant growth

Choose the most appropriate answer from the options given below :
A.
(A) Only
B.
(B) and (D) only
C.
(C) only
D.
(D) only
2021 Q80 JEE Mains MCQ
14 Mar 2026
Reducing smog is a mixture of :
A.
Smoke, fog and O3
B.
Smoke, fog and N2O3
C.
Smoke, fog and CH2 = CH $-$ CHO
D.
Smoke, fog and SO2
2021 Q81 JEE Mains MCQ
14 Mar 2026
The green house gas/es is (are) :

(A) Carbon dioxide

(B) Oxygen

(C) Water vapour

(D) Methane

Choose the most appropriate answer from the options given below :
A.
(A) and (C) only
B.
(A) and (B) only
C.
(A), (C) and (D) only
D.
(A) only
2021 Q82 JEE Mains MCQ
14 Mar 2026
The type of pollution that gets increased during the day time and in the presence of O3 is :
A.
Oxidising smog
B.
Global warming
C.
Acid rain
D.
Reducing smog
2021 Q83 JEE Mains MCQ
14 Mar 2026
The presence of ozone in troposphere :
A.
protects us from greenhouse effect
B.
protects us from the UV radiation
C.
protects us from the X-ray radiation
D.
generates photochemical smog
2021 Q84 JEE Mains MCQ
14 Mar 2026
Given below are two statements :

Statement I : The pH of rain water is normally 5.6.

Statement II : If the pH of rain water drops below 5.6, it is called acid rain.

In the light of the above statements, choose the correct answer from the options given below :
A.
Both Statement I and Statement II are true.
B.
Both Statement I and Statement II are false.
C.
Statement I is true but Statement II is false.
D.
Statement I is false but Statement II is true.
2021 Q85 JEE Mains MCQ
14 Mar 2026
Given below are two statements :

Statement I : An allotrope of oxygen is an important intermediate in the formation of reducing smog.

Statement II : Gases such as oxides of nitrogen and sulphur present in troposphere contribute to the formation of photochemical smog.

In the light of the above statements, choose the correct answer from the options given below :
A.
Statement I is false but Statement II is true
B.
Both Statement I and Statement II are false
C.
Both Statement I and Statement II are true
D.
Statement I is true but Statement II is false
2021 Q86 JEE Mains MCQ
14 Mar 2026
Given below are two statements :

Statement I : The value of the parameter "Biochemical Oxygen Demand (BOD)" is important for survival of aquatic life.

Statement II : The optimum value of BOD is 6.5 ppm.

In the light of the above statements, choose the most appropriate answer from the options given below :
A.
Statement I is false but Statement II is true
B.
Statement I is true but Statement II is false
C.
Both Statement I and Statement II are true
D.
Both Statement I and Statement II are false
2021 Q87 JEE Mains MCQ
14 Mar 2026
The gas released during anaerobic degradation of vegetation may lead to :
A.
Ozone hole
B.
Corrosion of metals
C.
Acid rain
D.
Global warming and cancer
2021 Q88 AP-EAPCET MCQ
20 May 2026

Identify the coldest region among the following layers of atmosphere.

A.
Troposphere
B.
Mesosphere
C.
Stratosphere
D.
Thermosphere
2021 Q89 AP-EAPCET MCQ
20 May 2026

Which among the following is not a greenhouse gas?

A.
Nitrous oxide
B.
Water vapour
C.
Sulphur dioxide
D.
Methane
2021 Q90 AP-EAPCET MCQ
20 May 2026

Which among the following has the highest concentration of PAN?

A.
Acid rain
B.
Oxidising smog
C.
Reducing smog
D.
Ozone
2021 Q91 AP-EAPCET MCQ
20 May 2026

Green chemistry refers to reactions which

A.
reduce the use and production of hazardous chemicals
B.
study of the extremely slow reactions
C.
are related to soil erosion
D.
study of green leaves
2020 Q92 JEE Mains MCQ
14 Mar 2026
The presence of soluble fluoride ion upto 1 ppm concentration in drinking water, is :
A.
safe for teeth
B.
harmful to skin
C.
harmful for teeth
D.
harmful to bones
2020 Q93 JEE Mains MCQ
14 Mar 2026
The condition that indicates a polluted environment is :
A.
BOD value of 5 ppm
B.
eutrophication
C.
0.03% of CO2 in the atmosphere
D.
pH of rain water to be 5.6
2020 Q94 JEE Mains MCQ
14 Mar 2026
The processes of calcination and roasting in metallurgical industries, respectively, can Iead to :
A.
Global warming and photochemical smog
B.
Photochemical smog and ozone layer depletion
C.
Photochemical smog and global warming
D.
Global warming and acid rain
2020 Q95 JEE Mains MCQ
14 Mar 2026
The incorrect statement(s) among (a) – (d) regarding acid rain is (are) :

(a) It can corrode water pipes.
(b) It can damage structures made up of stone.
(c) It cannot cause respiratory ailments in animals.
(d) It is not harmful for trees
A.
(c) and (d)
B.
(a), (b) and (d)
C.
(c) only
D.
(a), (c) and (d)
2020 Q96 JEE Mains MCQ
14 Mar 2026
Thermal power plants can lead to :
A.
Ozone layer depletion
B.
Blue baby syndrome
C.
Eutrophication
D.
Acid rain
2020 Q97 JEE Mains MCQ
14 Mar 2026
The statement that is not true about ozone is :
A.
In the stratosphere, CFCs release chlorine free radicals (Cl) which reacts with O3 to give chlorine dioxide radicals
B.
It is a toxic gas and its reaction with NO gives NO2.
C.
In the atmosphere, it is depleted by CFCs
D.
In the stratosphere, it forms a protective shield against UV radiation
2020 Q98 JEE Mains MCQ
14 Mar 2026
Biochemical Oxygen Demand (BOD) is the amount of oxygen required (in ppm) :
A.
for sustaining life in a water body.
B.
by anaerobic bacteria to breakdown inorganic waste present in a water body.
C.
for the photochemical breakdown of waste present in 1 m3 volume of a water body.
D.
by bacteria to break-down organic waste in a certain volume of a water sample.
2020 Q99 JEE Mains MCQ
14 Mar 2026
Among the gases (a) – (e), the gases that cause greenhouse effect are :
(a) CO2
(b) H2O
(c) CFCs
(d) O2
(e) O3
A.
(a), (b), (c) and (d)
B.
(a) and (d)
C.
(a), (b), (c) and (e)
D.
(a), (c), (d) and (e)
2020 Q100 TS-EAMCET MCQ
20 May 2026

The average atmospheric residence time is lowest for which of the given the greenhouse gas?

A.

Carbon dioxide

B.

Methane

C.

Nitrous oxide

D.

Freon