Organic Chemistry for JEE (Advanced) [1, 3 ed.] 9353503841, 9789353503840

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Contents 1.

Classification and Nomenclature of Organic

1.1

1.11 Aromatic Compounds 1.1-1.42

Compounds Introduction

1.1

1.3 Classification of Organic Compounds

1.1

1.3.1 1.3.2

Multiple Correct Answers Type

Hydrocarbons (Alkanes)

Matrix Match Type

1.39

Numerical Value Type

I40 141

1.17

1.5.3

TUPAC Rules for Haloalkanes

1.5.4

IUPAC Rules for Functional

UPAC Rules for Chain Terminating Functional Groups (-CHO, -COOH, -CONH,,-COC1,-C=N)

Archives

2.

Purification of Organic Compounds and Qualitative 21-2.40 and Quantitative Analysis 2.1 2.2

Introduction Extraction of Organic Compounds

1.18

2.3

Methods for Purification of Solids

2.4

Sublimation 2.3.1 2.3.2 Crystallisation Methods for Purification of Liquids

When the Names of Two or More

Substituents are Composed of Identical Words

1.18

1.5.8

When Both Double and Triple Bonds are Present in the Compound

1.19

1.5.9

Consist When Two or More Prefixes Identical Roman Letters (Words)

of

When the Organic

2.4.1

2.4.2 2.4.3

1.20

Molecule Contains

More Than One Similar Complex 1.20

Substituents

1.5.11

Poly-Functional Compounds Two Containing More than

Like-Functional Groups 1.5.12

not

Directly

1.6

Naming of Alicyclic

1.7

Naming of Tricyclo Compounds

1.8

Compounds

Bicyclo Compounds

1.9 Naming of Spiranes Ethers 1.10 Naming of Cyclic

Simple Distillation Fractional Distillation

Bell and Plate Type Fractionating Column Used in the Petroleum lndustry

2.4.4

Distillation Under Redueed Pressure

2.4.5

Steam Distillation

2.4.6

Differential Extraction

2.5 Chromatography 2.5.1

1.21

are When All the Three Like Groups Unbranched the Linked to

Carbon Chain

4

1.17

IUPAC Rules for Polyfunctional

Compounds

Single Correct Answer Type

Answers Key 1.17

Compounds

Exercises

1.2

1.17

1.5.10

1.27

Linked Comprehension Type

IUPAC Rules for Unsaturated Hydrocarbons (Alkenes and Alkynes)

1.5.7

Exercise 1.1

Solved Examples

1.2 1.2

IUPAC Rules for Naming Organic Compounds

1.5.6

Concept Application

1.2

1.5

1.5.5

given IUPAC Name

TUPAC Rules for Saturated

Homologous Series Characteristics of a Homologous Series

1.2

1.5.2

1.27

1.13 Writing the Structural Formula from the

129 1.29 I.35 1.35 I.37 1.38

1.4 Nomenclature of Organic Compounds 1.5.1

Compounds

1.1

1.2 Properties of Organic Compounds

1.26

1.12 Nomenclature of Substituted Benzene

1.21

Adsorption Chromatography

Partition Chromatography Gas Chronmatography 2.5.3 Qualitative Analysis of Organic Compounds 2.5.2

2.6

2.

2.5 2.5 2.6 2.7

2.6.1

Detection of C and H

2.7

1.22

2.6.2

Detection of Other Elements

2.7

1.24

1.25

2.7 Quantitative Analysis

1.26 1.26

2.8

Determination of Molecular Mass

2.9 Eudiometry or Gas Analysis

2.8 2.13

2.18

vi

Contents

2.10 Detection and Identification of Functional Group 2.11 Methods of Separation

of Mono-Functional

Organic Compounds fiom Binary Mixtures Concept Application Exercise 2.1 Solved Examples Exercises Single Correct Answer Type Multiple Correct Answers 7ipe Linked Comprehension Type

3.

2.26

2.32 2.35

3.4.10

Erythro and Threo Designation

2.3.

2.40 3.1-3.69

Positional Isomerism Functional Isomerism

3.1 3.1 3.1 3.2 3.2

Metamerism

3.3

Tautomerism

3.6

Chain or Nuclear Isomerism

3.2.1 3.2.2 3.2.3 3.2.4 3.2.5 3.2.6 3.2.7

Effect of Solvent on Enol Content Essential Conditions

3.2.8 3.2.9

Mechanism

3.3.1

3.3.2

Geometrical Isomerism in Alkenes (Rigidity of Double Bond) Distinction Between cis

and trans-Isomers 3.3.3 3.3.4

3.3.5

3.3.6 3.3.7 3.3.8

3.3.9

Atoms Syn and Anti Syn and Anti in

3.13

Alternating Axis of Symmetry

Conditions for Enantiomerism

3.7 3.8 3.9

Optical Activity

of t-Amines and t-Carbanion

ofthe Type (R,R,R,N) and (R,R,R,C°)

3.26

Racemic Mixture 3.8.1 Resolution of a Racemic Mixture

3.27

Stereospecific or Regiospecific Reactions

3.27

3.9.1

3.27

Stereoselective or Regioselective

Reactions 3.10 Asymmetric Synthesis or Asymmetric Induction 3.11 The importance of Stereochemistry 3.12 Projection Formulae 3.12.1 Intercon rsion of Wedge-Dash Formula to Fischer Formula

3.12.3

Sawhorse and Newman Projection

3.12.4

Newman Projection Formula

3.12.5

Conversion of Sawhorse and Newman

Formulae

Projection Formulae in Fischer and Vice Versa

3.13 Absolute Configuration 3.13.1 The R and S Configuration Descriptors 3.13.2 General Rules for Switching Ligands or Rotating Fischer Structures

3.13.3

3.28

3.28 3.29 3.30 3.30

3.15

3.19 3.19 3.19 3.20

3.31 3.31

3.31 3.33 3.33

3.33 3.34

Assignment of R, S Configuration of

Fischer Projection Containing Two More Chiral Centres

or

3.14 Conformational Isomerism

3.14.1 Sawhorse and Newman

Representations

3.14.2 Relative

3.34 3.35

3.35

Stability Staggered and Eclipsed Conformations of Ethane of

3.14.3 Conformational Isomers of Butane 3.14.4 Stability Order 3.15 Isomerism in Cyclic Compounds 3.16 Ring Strain and Stability 3.17 Conformations in Cycloalkanes and Cyclohexanes 3.18 Baeyer's Strain Theory 3.19 Stability of 3.19.1

3.30

Assignment of R, S Configuration in

Fischer Projection

3.18

Centre of Symmetry

3.26

Optical Activity of Biphenyl Compounds

3.13.4

Mirror Plane

(or Centre of Inversion) 3.4.4

3.12

3.15 or

3.6

3.12

Hydrazone,

or a-Plane

3.4.3

3.11

Phenylhydrazone, and Azo Compounds 3.15 Exo and Endo in Bicyclic Compounds 3.15

Optical Isomerism 3.4.1 Plane of Symmetry 3.4.2

3.9

3.14 3.15

Compounds

3.25

3.8

3.13

Geometrical Isomerism Across a Single Bond Geometrical Isomerism in Cyclic

3.22 3.22

3.5 Stereochemistry of Allenes

to Wedge-Dash Formula

The E andZ Nomenclature of

Geometrical Isomers Sequence Rules for Determining the Priority Order of Atoms or Groups Attached to Doubly Bonded Carbon

3.21

3.12.2 Interconversion of Fischer Formula 3.8

Triad System Containing Nitrogen 3.2.10 Increasing Order of Enol Content 3.2.11 Ring-Chain Isomerism Stereoisomerism

3.21 3.21

Isomers

Properties of Optical (Enantiomers)

Answers Ker

Structural Isomerism

Difference between d and/ D, L Configuration Descriptors (Relative Configuration)

3.4.9

Archives

3.2

3.20

2.3

2.38 2.39

3.3

3.4

2.25

Numerical Value Type

Introduction

3.4.6

Optical Isomers Meso and Racemic

3.4.7 3.4.8

2.26

2.37

3.1

Formula for the Number of

2.21

Matrix Match Tiype

Isomerism

3.4.5

Cyclohexane

36 3.36

3.36 3.37

3.38 3.39

3.39

3.39

Stability Order: Chair> Twist Boat Boat> Half Chair

3.40

Concept Application Solved Examples

3.43

Exercise 3.1

3.47

4.12 Hydrogen Bonding 4.13 Effect of Intermolecular Forces on

3.54

Type Answers Tipe Multiple Correct Linked Comprehension Tpe Matrix Match Type Answer

Mesomeric, Resonance, Steric Effects, Hyperconjugation, and H-Bonding in Acidic and Basic Characters of Organic Compounds

3.63 3.64 3.66 3.67

Archives

Introduction

4.2

Bonding 4.2.1

4.3

Reactive Intermediates

4.3.1 4.3.2 4.3.3

Stability of Reactive Intermediates

The Decreasing Order of Stabilities of Free Radicals The Decreasing Order of Stabilities of Carbanion

Salient Features

4.3.5

Carbenes (H,C:)

4.3.6

Radical Anions of Type (RC=CR)

4.44

4.1

4.20 Exo-2-norborane Carboxylic acid (1)

4.44

4.1 4.1 4.2

4.21 Dibasic Acids

4.44

4.22 Reason for the Acidic Character of the Monoanion of the Following Dibasic Acid

4.44

4.2

4.23 3-Butynoic Acid

4.44

4.24 Basic Character

4.44

4.25 RSH (Thiols or Mercaptans) (pK,*11)

4.45

4.3.7

4.2

4.3.8 Benzyne 4.4 Classification of Reagents 4.4.1 Electrophilic Reagent or Electrophile Nucleophilic Reagent or Nucleophile

4.29 Amphiprotic Species 4.30 Solvent Effect

4.7

4.20

Electromeric Effect

4.8 4.9

Mesomeric Effect Resonance Condition of Resonating Structures 4.9.1 4.9.2 Resonance Energy 4.9.3 The R.E. of Benzene 4.9.4 Characteristics of Resonance 4.9.5 Main Characteristics 4.9.6 Misconception Associated with Resonance 4.10 Steric Hindrance 4.11 Hyperconjugation

Hyperconjugation in Ethyl

Concept Application Exercise 4.1 Concept Application Exercise Solved Examples

4.8 4.10 4.10 4.11 4.15

4.21 4.22 4.22

4.22 4.22

5.

Organic Reaction Mechanism 5.1

Bond Energy

5.3 5.4

Reaction Energetics Types of Reactions 5.4.1 Substitution Reactions 5.4.2 SE Reaction SN Reaction

4.23 4.26

5.6

4.27

4.27

4.73 4.74 4..76 .78 4.79 4.79 4.82 5.1-5.78

Introduction

5.2

5.5

Carbocation

4.64 4.73

Single Correct Answer Type Multiple Correct Answers Tvpe Linked Comprehension Type Matrix Match Type Numerical Value Type Archives Answers Key

4.18

4.21

.59

4.2

Exercises

4.1

4.20

4.47 4.57

Compounds

4.8

4.6 Inductive Effect 4.6.1 Application of Inductive Effect 4.6.2 Effects on Carboxylic Acids 4.6.3 Basic Character of Amines 4.6.4 Basicity of Arylamines Basicity of Arylalkyl Amines 4.6.5

4.46 4.46 4.46 4.47

4.31 Aromatic, Anti-aromatic, and Non-aromatic

4.8 4.8

4.10

4.45

-NH,)

4.27 Soft and Hard Acids and Bases 4.28 Levelling Solvents

4.6

4.5 Factors Influencing Reactivity

4.11.1

4.26 Amides (R-

Nitrenes or Imidogenes, Azene,

or Imine (H-N: or RN:)

4.4.2

4.2

4.6

and (R_C-9)

43

4.19 Trans-4-tert-Butyl Cyclohexane-Carboxylic Acid (1)

4.2 4.3

4.3.4

4.43

4.18 Highly Branched Acids

4.1-4.82

Bonds The Breaking and Formation of

4.16 Sulphonic Acids

4.43

Answers Key

4.1

4.15 Carbonic Acid (H,CO,)

.35 4.43

4.17 Peroxy Acids

3.69

General Organic Chemistry

4.30

4.14 Application of Inductive, Electromeric,

3.60

Numerical Value Type

4.27

4.32

Physical Properties

3.54

Exercises

Single Correct

4.11.2 Application of Hyperconjugation

3.40

3.20 Substituted Cyclohexane

Substitution (SN) or Displacement Nucleophilic Bimolecular (DN-) Reaction 5.6.1 5.6.2

General Rule for SN2 Reaction

Nucleophilicity

5.1 5.1 5.2 5.6 5.6

5.6 5.6 5.9 5.11 5.12

viii

Contents 5.6.3

Effect of Solvent in Nucleophilicity Order Leaving Group or Fugncity Order

5.6.4 5.6.5

6.2.4

Attachment of Bond to Asymmetric

Wolff Kishner Reduction Methods Reduction of Acids, Carbonyl

5.13

S.7

5.18

6.2.5

S.8

Reaction Substitution Nucleophilie Internal (SN')

6.2.6

Compounds RX, Aleohol, Alkane and Alkynes with Red P+ HI to Alkane Using Unsaturated Hydrocarbons Grignard Reagent

Reaction Elimination Reactions 5.9.1 EI Mechanism

5..18

6.2.7

Preparation of CH,

5.19

6.2.8

5.20

6.2.9

Decarboxylation

5.9.2 E2 Mechanism 5.10 ElcB Reaction

5.21 5.24

S.11 Substitution Versus Elimination 5.11.1

Summary of Substitution

Vs. Elimination 5.12

.32 5.32

Summary of Basicity, Nucleophilicity,

and Fugacity 5.13 Addition Reactions 5.13.1

EA

5.33

5.36

(Electrophilic Addition) Reaction

5.13.2 Mechanism 5.13.3 Rearrangement of

Carbocation

5.3

36

Nucleophilic Addition (NA) Reaction 5.15 Polar Addition of Halogens and Halogen Acids (rans-Addition) 5.15.1 Addition 5.15.2 Addition to Alkynes 5.16 Carbocation Rearrangement

of Cl

Rearrangement of the Alicyclic Ring System (Demjanov rearrangement) 5.17.1 Some Examples of Ring Contraction

5.18 Stereochemical Reactions 5.18.1 Addition Reaction 5.18.2 Hydroxylation 5.18.3 Debromination and

Dehydrohalogenation Reaction Concept Application Exercise 5.1 Solved Examples Exercises

5.37

5.37 5.37 5.37

5.37 5.38 5.40 5.40 5.40

5.42

5.59 S.62

Linked Comprehension Type Matrix Malch Type Numerical Value Type Archives Answers Key

Cycloalkanes

Alkanes

6.1.1

Nomenclature 6.2 Preparation of Alkanes 6.2.1 Reduction of Alkyl Halides 6.2.2 Mechanism with Zn-Acid

lodination

6.3 6.4 6.4 6.4

6.6 6.6 6.7 6.7 6.8

6.8 6.8 6.8 6.8 6.8

6.11 6.11

6.12 6.13

6.13 6.14

6.4.3

Finkelstein Reaction

6.4.4

Fluorination (Swart's Reaction)

6.4.5

Nitration

6.4.6

6.14

Sulphonation

6.4.7 6.4.8 6.4.9 6.4.10 6.4.11

Combustion Catalytic Oxidation

6.14

Isomerisation Aromatisation

6.14 .14

6.14 6.14 6.14 6.15

Cracking (Pyrolysis or Thermal

Decomposition) Singlet Methylene Insertion Between

Petroleum 6.5.1

5.50

5.66

Halogenation in Aliphatic Compounds

(C-H) Bonds 6.5

Multiple Correct Answers Type

Reactions of Alkanes

6.4.12

5.41

5.62

Physical Properties of Hydrocarbons 6.4.1 6.4.2

5.37

Single Correct Answer Type

Alkanes and

6.3 6.4

Intermediate

5.14

5.17

Free Radical Mechanism 6.2.10 Wurtz Reaction 6.2.11 Fittig Reaction 6.2.12 Wurtz-Fittig Reaction 6.2.13 Ulmann Reaction 6.2.14 Frankland Reaction 6.2.15 Kolbe's Electrolytic Reaction 6.2.16 Mechanism (Free Radical) 6.2.17 Corey-House Synthesis 6.2.18 Hydroboration Reaction

29

5.11.2 Orientation in Elimination Reactions

6.1

5.12 5.13

Rcduction of Carbonyl Compound to Alkanc by Clemmensen and

CAtom Aromatic Substitution Nucleophilie (ArSN)

5.9

6.

6.2.3

Refining of Petroleum

6.15 .15 b..lo 6.16

6.5.2

Knocking

o.I

6.5.3

Octane Number

o.1

6.5.4

Anti-Knocking Agents or Gasoline

6.5.5

Additives Cetane Number

b.18 o.18

5.69

6.6

Coal

o.18

5.72

6.7

Cycloalkanes

6.19

.75 .,76

6.7.1

6.7.2

5.78 6.1-6.45 6.1 6.1 6.3

6.3 6.3

Nomenclature ot Cycloalkanes Bicyelo, Tricyclo, Spiro, and

19

Polyeyclic Compounds

20 22

6.8

Preparation of Cyeloalkanes

6.9

Reactions of Cycloalkanes

6.26

6.9.1 6.9.2 6.9.3

6.26

Hydrogenation Reactions Free Radical Substitution Electroplilic Addition Reactions Exercise 6.1 Concept Application Exercise 6.2

Concept Application

6.26

6.26

6.27 6.29

Contents ix

7.14

and 7.15 Hydroxylation

.30

Sohved Exanmples

6.34

Exercises Single Correct Answer Type

Multiple Correct Answers Tpe

6.38

Linked Comprehension Tipe

6.39

Matrix Match Type Numerical Valhue Type

6.41

Answers Key

6.45

7.1

7.16.1 7.17

Equivalent (D.B.E.) 7.3

8

Preparation of Alkenes

7.3.1

Dehydration of Alcohols

7.3.2

Dehydrohalogenation of Alkyl Halide

7.3.3

Dehalogenation

11

14 .14 .14

5.14

.14 o.14

6.14 6.14 6.15

7.5.3

Relative Stabilities of Alkene from Heat of Hydrogenation AH

7.5.4

Relative Stabilities of Alkenes from Heat of Combustion:

7.3 7.5 7.5 1.7 7.8

(AH)

7.8 7.9 7.10

7.10 7.10 7.10 7.10 7.10

7.13

7.6

Allylic Substitution

7.7

Diels-Alder Reaction

T.21

6.16

7.8

Polar Addition of Halogens, Their Derivatives,

6.17

6.11

Addition Reactions

Exercises

7.13

6.15 6.16

7.5.5

Reverse Problems

Multiple Correct Answers Type Linked Comprehension Type Matrix Match Type Numerical Value Type Archives Answers Key 8.

Alkynes 8.1

Introduction

8.1

7.8.2

7.24 7.25

8.2

Isomerism in Alkynes

8.3

Preparation of Alkynes

8.2 8.3 8.3 8.4 8.4

Peroxide Effect or Kharasch Effect

7.29

8.3.1

Industrial Method

6.18

7.11 Dimerisation 7.11.1 Mechanism 7.12 Alkylation 7.12.1 Mechanism

7.29 7.29 7.31

8.3.2

Berthelot Synthesis

8.3.3

From Lime

7.13 Hydration of Alkenes to Alcohols

7.31

6.26

Halobydrin Formation

8.1-8.48

7.10 Rearrangement During Electrophilic Addition

6.26

1.13.1 Acid-Catalysed Reaction with Water

7.31

7.31

7.13.2 Oxymercuration-Demercuration

Reaction

o26

7.13.3 Hydroboration Oxidation of Alkenes

.26

to Alcohols 7.13.4 Treating Haloalkene with Moist Ag,O

6.29

7.87 7.89

7.24

6.18

6.22

7.87

7.23

7.9

6.20

80 7.85

and Halogen Acids (Anti-Addition) 1.8.1 Markovnikov's Rule

6.18

6.19 6.19

7.67 7.67 7.75

Single Correct Answer Type

7.14 7.14 7.18

6.15

Reverse Problems

7.20 Alkadienes 7.20.1 Nomenclature of Dienes 7.20.2 Stability of Conjugated Diene 7.52 7.20.3 Stabilities of Conjugated Dienes, Alkynes, and Alkenes 7.53 7.20.4 Conformations and Electrophilic Addition Reaction of Buta-1,3-Diene 7.53 7.21 Electrophilic Addition Reaction in Dienes 7.53 7.21.1 Mechanism 7.53 7.21.2 Effect of Temperature 7.54 7.21.3 Thermodynamic Control and Kinetic Control of 1,2- and 1,4-addition Products 7.54 7.21.4 Effect of Solvent 7.55 Concept Application Exercise 7.1 7.56 Concept Application Exercise 7.2 7.61 Solved Examples 7.61

7.3.4

3 .13

Hydroboration of Alkynes (Predominantly to cis-Alkene) 7.3.5 Reduction of Alkynes to Alkenes 7.4 Physical Properties 7.4.1 Boiling Point (b.p.) 7.4.2 Melting Point (m.p.) 7.4.3 Solubilities 7.5 Chemical Reactions 7.5.1 Hydrogenation 7.5.2 Mechanism of Catalytic Hydrogenation

1.42 7.43 743 7.46 7.47 7.51 7.51 7.51 7.51

7.18 Conversion of Alkane to Alkene and Alkyne 7.19 Ascent and Descent of Series in Alkenes

7.1

7.2 Degree of Unsaturation (D.U.) or Index of Hydrogen Deficiency (.H.D.) or Double Bond 8

7.41

Ozonolysis of Alkenes 7.17.1

7.1-7.89

Introduction

7.40 7.40

Syn-hydroxylation

6.44

and Alkadienes

7.39

of Alkene 7.15.3 Mechanism ofAnti-hydroxylation of Alkenes 7.16 Oxidative Cleavage

6.44

Alkenes

Shifting of Double Bond

7.15.1 Anti-Hydroxylation 7.15.2 Mechanism of

6.34

Archives

7.

Isomerisation

or (AgCl+ H,O) to Give Alcohol

7.32 7.3 7.36

8.4 8.5

8.3.4 8.3.5

(CaO), Coke (C), and Double Dehydrohalogenation From a-Diketone

8.3.6

Kolbe's Electrolysis

H,O

Physical Properties of Alkynes Chemical Properties of Alkynes 8.5.1 8.5.2

8.5.3 8.5.4

8.4

8.5 8.5 8.6 8.11

Reduction

8.11

Addition of Halogens Addition of H,O (Kuchrov's Reaction) Addition of Halogen Acid and Other

8.11 8.12

Compounds

8.14

X

9.7

Contents

8.6

8.7

Methanal Reaction of Ethyne with Terminal Addition of (Formaldehyde) (OR)

8.15 8.17 8.17 8.18 8.18

Alkyne to Carbonyl Compounds Propargylic Halogenation

Mechanism

8.8

8.9

8.7.1 to an Alkyne Nucleophilic Addition and Alkynes Alkenes Reactivity of 8.8.1 with Aqueous or Hydroxylation of Alkyne Solution (Baeyer's Reagent)

Neutral KMnO, (Test for Unsaturation)

8.118

8.10.1

8.11 Ozonolysis of Alkynes

of Alkyne

S.12 Hydroboration Oxidation (HBO) HBO Reaction on 8.12.1 Limitation

8.23 8.24

8.13 Reaction of Sia,BH on Alkyme 8.14

Synthesis

by the

Use

of Alkynes

S.15 Conversion of One Diastereomer to Another 8.16 Polymerisation and Isomerisation of Alkynes 8.16.1 Linear Polymerisation of Ethyne 8.17 Cyclic Polymerisation of Ethyne 8.18 Polymerisation of Propyne 8.19 Isomerisation 8.20 Distinction Between Alkene and Alkyne 8.21 Ascent and Descent Series in Alkynes

Concept Application

9.

9.8

Exercise 8.1

8.26

Effects of Photochemical Smog How can Petrochemical Smog be

9.9

9.8.2

Ozone Hole

9.8.3

Effects of Depletion of the Ozone Layer

Water Pollution

9.6

9.9.1 9.9.2

9.6

9.9.3

Causes of Water Pollution International Standards for Drinking Water Prevention of Water Pollution

Soil Pollution

9.10.1

Composition of the Soil

9.10.2 9.10.3

Loam Soil Sources of Soil Pollution

9.3

8.27

9.12 Strategies to Control Environmental Pollution

8.27

9.13 Green Chemistry 9.13.1 Definition 9.13.2 Methods Used in Green Chemistry 9.13.3 Nobel Laureates in Green Chemistry and Metathesis 9.14 Green Chemistry in Day-to-Day Life 9.14.1 Dry Cleaning of Clothes

9.8 9.9

.28

8.28 8.28

8.29 8.29 8.29

Solved Examples

8.34

9.14.2 Bleaching of Paper 9.14.3 Synthesis of Chemicals

Single Correct Answer Type

8.34

9.15 Some Suggestions for Reducing Pollution

Multiple Correct Answers Type Linked Comprehension Type

8.37

Exercises

Matrix Match Type

8.44

Single Correct Answer T+ype Multiple Correct Answers Type

Numerical Value Type Archives Answers Key

8.47

Numerical Value Type

Environmental Chemistry

9.1-9.13

Solutions

9.1 Introduction 9.2 Environmental Pollution 9.3 Atmospheric Pollution 9.3.1 Troposphere Pollution 9.4 Global Warming and Greenhouse Effect 9.4.1 How to Reduce the Rate of

9.1 9.1

Global Warming?

9.3

Chapter 1 Chapter 2 Chapter 3 Chapter 4 Chapter 5 Chapter 6 Chapter 7

9.6

9.7 9.7 9.7 9.7 9.7 9.7

9.11 Some Developments About Waste Recycling

Exercises

Acid Rain 9.5.1 Harmful Effects of Acid Rains 9.5.2 Taj Mahal and Acid Rain 9.5.3 How to Reduce Acid Rain Particulate Pollutants

9.5 9.5 9.5

.26

8.30

9.5

9.5 9.5

Stratosphere Pollution Formation and Breakdown of Ozone 9.8.1

9.10

of the

Terminal Alkyne

9.4 94 9.5

Formation of Photochemical Smog

Controlled?

8.19 8.20 8.23

Reverse Problems

of Compounds

9.7.3

8.19

8.10 Oxidative Cleavage

Smog 9.7.1 9.7.2

8.40

8.47

8.48

9.1 9.1 9.2

9.3 9.3 9.3 9.4 9.4

Archives Answers Key

9.9

9.9 9.9 9.10 9.10

9.10 9.10 9.10 9.11 9.11 9.12 9.12 9.13

9.13 S.1-S.106 S.

S.13 S.31 S.43 S.59 S.72

Chapter8

S.93

Chapter 9

S.106

Appendix: Chapterwise Solved January 2019 JEE Main

Questions (AlI Sets)

A.l-A.

Enviromental Chemistry

9

a1 INTRODUCTION anmental studies deal with the social, economical, biological, and chemical interrelations with our suroundings. It deals physical a of the origin, transport, reactions, effects the study withti and fates in the environment. species afchemical

92 ENVIRONMENTAL POLLUTION Substance, which causes pollution, is known as pollutant. Polutants can be solid, liquid or gaseous substances present greater concentration than in natural abundance and are Tmduced due to human activities or due to natural

happenings.

Pollutants can be degradable, like discarded vegetables which aDidly break down by natural processes. Pollutants which are

slowly degradable,

remain in the environment in an unchanged form for many decades. For example, substances such as

dichlorodiphenyltriclorethane (DDT), plastic materials, heavy

2. Particulate Smog etc.

9.3.1.1

nto the

environment

difficult to remove. These pollutants natural degraded by processes and are harmful to living organisms. Pollutants originate from a source and get transported Dy aur or water or are dumped into the soil by human beings.

2S0, (g)+0, (g)> 2SO, (g) The reaction

H,0,.

high

yield significant quantities of nitric oxide (NO) and nitrogen dioxide (NO,) as given below: 1483K

N, (g)+O, (g)

hand, conatins N,, O2, 0, and

2NO

instantly

with

(g)+ O, (g)

>

2NO (g)

O, to give NO,

2NO, (g)

Rate of production of NO, is faster when nitrie oxide reacts with O, in the stratosphere.

of O, in the stratosphere prevents about 99.5%

Sun's harmful ultraviolet (UV) radiations from reaching the

SSurface and thereby protecting humans and other animals Trom its effect.

NO

(g)+0, (g)-> NO, (g)+0, (g)

The irritant red haze in the tratic and congested places is due to oxides of nitrogen. Higher concentrations of NO, damage the leaves of plants and retard the rate of photosynthesis. NO, is a lung irritant that can lead to an acute respiratory disease in children. It is toxie to living tissues also. It is also harmful to various textile fibres and metals.

.3.1 TROPOSPHERE POLLUTION

Tropos nerie pollution occurs due to the presence of undesirable gaseous and

carbon, sulphur, H,S, O,, hydrocarbons and other oxidants.

and

temperature) when fossil fuel is burnt, N, and O, combine to

NO reacts

particles in the air. The following are the major particulate pollutants present in the troposphere: Gaseous air pollutants: These are oxides of nitrogen,

promoted by 0,

they combine to form oxides of nitrogen. NO, is oxidized to nitrate ion, NO9 which is washed into soil, where it serves as a fertilizer. In an automobile engine, (at

formation.

O

also be

2. Oxides of nitrogen: N, and O, are the main constituents of air. These gases do not react with each other at a normal temperature. At high altitudes when lightening strikes.

d.This is the region of strong air movement and cloud

23seou s

can

SO, (g)+0, (g)> SO, (9)+0, (g SO, (g)+H,O (1)>H,SO, (aq)

ulent, dusty zone containing air, much water vapour and

e

when

of particulate matter in polluted air catalyses the oxidation of SO, to SO

and 50 km above sea level lies stratosphere. Troposphere 1s

the other

sulphur are produced

stiffness of flower buds which eventually fall off from plants. Uncatalysed oxidation of SO, is slow. However, the presence

Beightof-10 km from sea level. Above the troposphere, between

on

or

in human beings. It causes irritation to the eyes, resulting in tears and redness. High concentration of SO, leads to

are

little waterstratosphere, vapour.

Oxides

species, SO,, is a gas that is poisonous to both animals and plants and even a low concentration of SO,, causes respiratory diseases e.g., bronchitis, emphysema, asthma

be lowest region of atmosphere in which the human beings along ith other organisms live is called troposphere. t extends up to the

ne presence

sulphur:

sulphur containing fossil fuel is burnt. The most common

9.3 ATMOSPHERIC POLLUTION

he

Gaseous Air Pollutants

1. Oxides of

metals, many chemicals, nuclear wastes etc., once released camnot be

pollutants: These are dust, fumes, smoke, mist,

3.

Hydrocarbons: Hydrocarbons are composed of hydrogen

and carbon

only

and

are

formed by incomplete

combustion

9.2 Organic Chemistry of fuel used in automobiles.

Hydrocarbons are carcinogenic,

1.e., they cause cancer. They harm plants by causing ageing,

breakdown of tissues and shedding of leaves, flowers and

9.4 GLOBAL WARMING AND GREENHOUSE EFFECT 1. About 75% ofthe solar energy reaching the earth is absorhed

twigs.

by the earth's surface, which increases its temperature The rest of the heat radiates back to the atmosphere. Sama

4. Oxides of carbon: a. Carbon,monoxide:

of the heat is trapped by gases such as CO, CH.,

i. CO is a colourless and odourless gas, highly poisonous to living beings because of its ability to block the of O, to the organs and tissues. i. It is produced as a result of incomplete combustion of

delivery

carbon. ii. CO is mainly released into the air by automobile

chlorofluorocarbon compounds (CFCs) and water vanou in the atmosphere. Thus, they add to the heating of the atmosphere. This causes global warming. 2. In cold places flowers, vegetables and fruits are grown in glass covered areas called greenhouse. Just as the glass in a greenhouse holds the sun's warmth inside, atmosphere

exhaust and by incomplete combustion of coal, petrol,

traps the sun's heat near the earth's surface and keeps t

firewood. etc. iv. CO is poisonous because it binds to haemoglobin to

warm. This is called natural greenhouse effect becauseit maintains the temperature and makes the earth perfect for

form carboxyhaemoglobin, which is about 300 times

life.

more stable than the oxygen-haemoglobin complex. In

blood, when the concentration of carboxyhaemoglobin reaches about 3-4%, the oxygen carrying capacity

3. In a greenhouse, visible light passes through the transparent

glass and heats up the soil and the plants. The warm soil and plants emit infrared radiations. Since glass is opaque to infrared (heat) radiations, it partly reflects and partly absorbs these radiations. This mechanism keeps the energy of the

of blood is greatly reduced. This oxygen deficieney, results into headache, nervousness, weak eyesight and cardiovascular disorder.

sun trapped in the greenhouse. Similarly, CO, molecules

V. In pregnant women who have the habit of smoking the increased CO level in blood may induce premature

also trap heat as they are transparent to sunlight but not to the heat radiation. If the amount ofCO, crosses the delicate proportion of 0.03%, the natural greenhouse balance may get disturbed. CO, is the major contr+butor to global warming

birth, spontaneous abortions and deformed babies. b. Carbon dioxide:

i CO, is released into the atmosphere by respiration, burning offossil fucls for energy, and by decomposition of limestone during the manufacture of cement. i. It is also emitted during volcanic eruptions. ii. CO, gas is confined to troposphere only. Normally it forms about 0.03% by volume of the atmosphere. iv. Excess of CO, in the air is removed by green plants and this maintains an appropriate level of CO, in the

4. Besides CO,, other greenhouse gases are CH, water vapour. nitrous oxide, CFCs and ozone. CH, is produced nanuraly when vegetation is burnt, digested or rotted in the absence of oxygen. Large amounts of methane are released in paddy fields, coal mines, from rotting garbage dumps and by fossil

atmosphere. Green plants require CO, for photosynthesis and they,

conditioning etc. CFCs are also damaging the ozone layer. Nitrous oxide occurs naturally in the environment. In years, their quantities have increased significantly due to the

recent

in turn, emit oxygen, thus maintaining the delicate

use of chemical fertilizers and the burning of fossil faeis.

balance

If these trends continue, the average global temperanure will increase to a level which may lead to melting of

v.

(Fig. 9.1).

fuels. CFCs are man-made industrial chemicals used in air

vi. Deforestation and buming of fossil fuel increases the CO, level and disturb the balance in the atmosphere. vii. The increased amount of CO, in the air is mainly responsible for global warming.

polar

Ce caps and flooding of low lying areas all over the earth.

Increase in the global temperature increases the of infectious diseases like dengue, malaria, yellow teve

incidence

sleeping sickness etc.

Solar energy passing through atmosphere

containing CO2

Infrared radiation (heat) re-emitted by earth and absorbed by CO2 and H20

and H20 vapour Absorption of energy in the

vapour in lower

visible region

EARTH STAGE 1

Heat radiated back to earth

atmosphere

by CO2 and H20 vapours

EARTH STAGE 2 Fig.

9.1

Stages

to show

production

of

greenhouse

EARTH STAGE 3 effect

oW TO

EDUCE THE RATE

OF

WARMING?

GLOBAL

2.

Oxides of nitrogen and

warming ist minimise the use of automobiles. upon the situat

global-

enalng

set

uation, one can use bicycle, transport forcarpool.Wesshould plant more treespublic to increase the ot Avoid buming dry leaves, wood etc. It is

hlic places and work places, because it is

amoke m

public

e

one

nly1ortihe o n e

should

who is smoking but also for

avoid

it.

3.

illegal to

harmful

not

Burning

(which contain

sulphur and coal and oil in power stations and diesel in motor engines as

furnaces or petrol produce sulphur dioxide and nitrogen oxides. and NO, after Oxidation and reaction with water are SO, major contributors to acid rain, because

matter than has

pH of 5.6 due to the reaction of rain water presence with Co, present in the atmosphere jons formed by

a

4.

When the pH of the rain water

Ammonium salts

also formed and can be seen as haze (aerosol of fine particles). Aerosol particles of oxides or ammonium salts in rain drops result in wet-deposition. SO, is also absorbed directly on both solid and liquid ground surfaces and is thus deposited as an

HCO,(aq)H° (aq) + H,cog (aq)

drops below 5.6, it is called

polluted air usually contains particulate catalyse the oxidation.

2S0, (g)+0, g) +2H,0(0)2H,SO, (aq) 4NO, (g)+ 0, (g)+ 2H,0 ()>4HNO, (aq)

the

HO )+CO, (g)H,CO, (aq) acid rain.

of fossil fuels

and

others, and therefore,

5 ACID RAIN fH

be blown

nitrogenous matter) such

E

Nomally rain water

sulphur which are acidic in

nature by wind along with solid in the atmosphere and finally settle down either onparticles the ground as dry deposition or in water, fog and snow as wet deposition (Fig. 9.2). can

duce

Environmental Chemistry 9.3

are

atmospheric

dry-deposition.

Sulphuric acid (HSO) Nitric acid (HNO;)

Dry fallout

Acid snow ater vapour

Acid rain

cloud)

Sulphur dioxide

and rogen dioxide emission

Damage to Vegetation

Aguatic life in danger

Fig. 9.2

Acid deposition

.5.1 HARMFUL EFFECTS OF ACID RAINS it

and plants *ACIdrain is harmful for agriculture,needed for their growth. nutrients Oves and washes away and animals. in human beings ailments respiratory as

trees

Causes

to reach

water fows as ground n e n acid rain falls and life in aquatic animal and vers, lakes, etc., it affects plants

*

ecosystemn. Corrodes water pipes resulting

in the leaching ol heavy into the drinking

water,

iron, lead and copper made etals other structures buildings and rain damages 1d stone or metal. rain. affected by acid India has been such as

he Taj Mahal in

of

9.5.2 TAJ MAHAL

AND

The air around the

of

ACID RAIN

city where the Taj Mahal is contains fairly high levels Agra, located, of sulphur and mainly due to a large number of industries nitrogen oxides. It is and power the area. Use of plants around poor quality of coal, kerosene and firewood as fuel for domestie purposes add up to this acid rain reacts with

marble,

(CaCO,) ofTaj Mahal (CaCO, causing damage

to

problem. The resulting

+H,SO,> CaSO, +H,O+CO,)

monument. As a result, the being slowly disfigured monument is and the marble is lustreless. getting discoloured and 1. Under the plan, clearing the air in the area that "Taj Trapezium-an includes the town of Agra, Firozabad, Mathura and

9.4 Organic Chemistry inside Bharatpur. More than 2000 polluting industries lying use the to gas over switch would the trapezium ofnatural or or oil. coal of instead liquefied petrolcum gas more than half a 2. A neW natural gas pipeline would bring this arca. to million cubic metres of natural gas a day be encouraged to use 3. People living in the city will also coal, kerosene or of liquefied petroleum gas in place

firewood.

of Taj plying on highways content diesel. encouraged to use low sulphur in the

4. Vehicles

vicinity

e.

The effect of particulate

pollutants are largely dependen

on the particle size. Air-borne particles such as ust, fumes, mist, ete. are dangerous for human calth.

Particulate pollutants bigger than 5 microns are likel to lodge in the nasal passage, whereas particles of abo

1.0 micron enter into lungs casily.

ut

f. Lead used to be a major air pollutant emitted by vehicles

Leaded petrol used to be the primary source of air-borne

would be

lead emission in Indian cities. This problem has now

been overcome by using unleaded petrol in most of the cities in India. Lead interferes with the development and

9.5.3 HoW

TO REDUCE ACID

RAIN

maturation of red blood cells.

1. This can be done by reducing the emission of SO, and NO, less vehicles driven by fossil fuels for power fossil fuels; use less sulphur natural use should gas which is a plants and industries. We less with coal sulphur content. better fuel than coal or use reduce the effect to cars in used converters must be in the

atmosphere.

We should

use

content

2.

9.7 SMOG The word smog is derived from smoke and fog. This is the most common example of air pollution that occurs in many cities

throughout the world. There are two types of smog: 1. Classical smog occurs in cool humid chimate. It is a mixture

Catalytic

atmosphere. The main component of ceramic honeycomb coated with precious the converter is a metals-Pd, Pt and Rh. The exhaust gases containing

of exhaust fumes

of smoke, fog and SO, Chemically it is a reducing mixture

on the

unburnt fuel, CO and NO, when pass

through the converter

and so it is also called as reducing smog.

2. Photochemical smog occurs in warm, dry and sunny climate. The main components of the photochemical smog result from the action of sunlight on unsaturated

at 573 K, are converted into C0, and N,. soil by adding powdered 3. We can also reduce the acidity ofthe of the acidity the soil. limestone to neutralize

hydrocarbons and nitrogen oxides produced by automobiles and factories. Photochemical smog has high concentration of oxidizing agents and is, therefore, called as oxidising

9.6 PARTICULATE POLLUTANTS

smog.

Particulate pollutants are the minute solid particles or liquid smoke in air. These are present in vehicle emissions, industries. from ash from fires, dust particles and may be viable or non-viable. Particulates in the

droplets particles

atmosphere 1. The viable particulates e.g., bacteria, fungi, moulds, algae in the etc., are minute living organisms that are dispersed atmosphere. Human beings are allergic to some of the fungi found in air. They can also cause plant diseases.

2. Non-viable particulates may be classified according to their nature and size as follows: of solid a. Smoke particulates consist of solid or mixture and liquid particles formed during combustion or organic matter. Examples are cigarette smoke, smoke from

burning of fossil fuel, garbage and dry leaves, oil

smoke

etc. b. Dust is composed of fine solid particles (over I um

in diameter), produced during crushing, grinding and attribution of solid materials. Sand from sand blasting, saw dust from wood works, pulverized coal, cement and fly ash from factories, dust storms etc., are some typical examples of this typc particulate emission.

of

9.7.1 FORMATION OF PHOTOCHEMICAL SMOG When fossil fuels are burnt, a variety of pollutants are emitted that are emitted into the earth's troposphere. Two of the pollutants oxide nitric and (NO). When fuels)

are

hydrocarbons (unburnt

these pollutants build up to sufficiently reaction

occurs

NO is converted absorbs energy from

sunlight and

a

chain

breaks up into nitric oxide and

free oxygen atom.

(1)

NO, (g) N O (g)+ O(g) Oxygen

atoms are very reactive and combine

with the O.

in

air to produce ozone.

O (g)+0, ( g ) 0 , (g) The ozone formed in the above reaction (ii) reacts rapidy with the NO (g) fornmed in the reaction (i) to regenerate NO.. NO; to haze. IS a brown gas and at sufliciently high levels can contribute

(11) NO (g)+O, (g)> NO, (g) +0, (g) Ozone is a toxic gas and both NO, and O, are strong oxdizng agents and can react with the unburnt hydrocarbons in the pollueu air to produce chemicals such as formaldehyde, acrolein a peroxyacetyl nitrate (PAN).

through air and form mists. d. Fumes are generally obtaincd by the condensation of

CH, CHCH-O

solvents, metals and metallic oxides form fume particles.

levels,

sunlight in which dioxide (NO,). This NO, in um into nitrogen

c. Mists are produced by particles of spray liquids and by Condensation of vapours in air. Examples are sulphuric acid mist and herbicides that miss their targets and travel

vapours during sublimation, distillation, boiling and several other chemical reactions. Generally, organic

high

from their interaction with

3C1,

20,

3CH, = 0 +3H,O Formaldehyde CH, C O0NO,

Acrolein Peroxyacetyl nitrate (PAN)

Environmental Chemistry

9.5

parts etc. Once CFC's are released in the atmosphere, they

41.2 EFFECTS ceCECTS OF OF PHOTOCHEMICAL SMOG

mix with the normal atmospheric gases ándeventually reach MCOmponents ofphotochemical smog are ozone, nitric lein, formaldehy and peroxyacetyl nitrate (PAN). health problems. Both ozone and PAN ause

commonc

serious

They

s nowerful eye irritants. Ozone and nitric oxide irritate and throat and their high concentration causes the nose a chest pain, dryness of the dificulty in breathing.

adache,

hea

throat, cough

and

the stratosphere. In stratosphere, they get broken down by UV radiations, releasing chlorine free radica.

powerful CF,CL, (g)

I

(g) + F,CI

(g)

)

The chlorine radical then react with stratospheric ozone to form chlorine monoxide radicals and molecular oxygen.

CI (g)+O, (g)-> CIO (g)+O, ()

(ii)

2.Photochemica smog leads to cracking of rubber and

Reaction of chlorine monoxide radical with atomic oxygen

ensive damage to plant life. It also causes corrosion af metals, stones, building materials, rubber and painted

produces

more

chlorine radicals.

CiO (g)+O(g)> CI (g)+0, (g)

(111)

surtaces.

and The chlorine radicals are continuously regenerated cause the breakdown of ozone. Thus, CFCs are transporting chlorine radicals into the agents for continuously generating stratosphere and damaging the ozone layer.

CAN PETROCHEMICAL SMoG BE 073 HOW CONTROLLED?

1. Control of primary precursors of photochemical smog, Such as NO, and hydrocarbons, the secondary precursors

such

as ozone

and PAN, the

photochemical

smog will

automatically be reduced.

9.8.2 OzONE HOLE of ozone layer commonly known as ozone hole over the South Pole, it was found that a unique set of conditions was

Depletion

Usually catalytic converters are used in the automobiles, which prevent the release ofnitrogen oxide and hydrocarbons to the atmosphere. 3. Certain plants e.g., Pinus, Juniparus, Quercus, Pyrus and Vitis can metabolise nitrogen oxide and therefore, their

plantation could help in this matter.

responsible for the ozone hole. In summer season, NO, and CH,

react with CIO (reaction iv) and chlorine atoms (reaction v)

forming chlorine sinks, preventing much ozone depletion, whereas

in winter, special type of clouds called polar stratospherie clouds are formed over Antarctica. These polar stratospheric clouds

provide surface on which chlorine nitrate formed (reaction iv) gets

hydrolysed to form hýpochlorous acid (HCIO) (reaction (vi)

9.8STRATOSPHERE POLLUTION

It also reacts with HCl produced as per reaction (v) to give Ch-

9.8.1 FORMATION AND BREAKDOwN OF OZONE 1. The upper stratosphere consists of considerable amount of ozone (0), which protects us from the harmful ultraviolet (Uv) radíations (à 255 nm) coming from the sun. These radiations cause skin cancer (melanoma) in humans. Therefore, it is important to maintain the ozone shield. .

CIO (g)+NO, (g)-> CIONO, (g)

CI(g)+CH, (g)> CH, (g)+HCl(g) CIONO, (g) +H,O (g)HOCI (9)+ HNO, (g) CIONO, (g)+ HCl (g)> Cl, (g)+ HN0, (g)

iv) (v) (vi) (vii)

When sunlight returns to the Antarctica in the spring.

Ozone in the stratosphere is a product of UV radiations

the sun's warmth breaks up the clouds and HOCl and Cl, are

acting on O, molecules. The UV radiations split apart molecular oxygen into free oxygen (0) atoms. These oxygen

photolysed by sunlight, as given in reactions (vii) and (ix),

atoms combine with the molecular oxygen to form ozone.

0,(g)

Cl,(g)

O (g)+O (g)

O(g)+0, ()

0,

molecules.

and

OH () CI(g)

21(g)

(viin)

(ix)

The chloride radicals thus formed, intiate the chain reaction for ozone depletion as deseribed earlier.

O2one is thermodynamically unstable and decomposes molecular oxygen, Thus, a dynamic equilibrium exists

eween the production

HOCI(g)

decomposition

of

ozone

*Depletion of protective O layer happens due to the presence of certain chemicals in the stratosphere. e.g.

Cnlorofluorocarbon compounds,(CFCs) also' known as

On.These compounds are non-reaetive, non-flammable, 0n-toxici organic moleculésand therefore used in tiigetatora, air icónditioners in the produotión of plastic 0a andby the 'electronicindustry for icleaning computer .

19i£

9.8.3 EFFECTS OF DEPLETION OF THE OZONE LAYER With the depletion of 0zone layer, more UV radiation filters into tropósphere. UV radiations lead to ageing of skin, cataract,

Sunburn, _kin cancer. killing of many phytóplanktons, damage to

fishproductivity ete

Plant proteins get easily affected by the UV radiátions which

leadsto the harmful inutation of cells.It also increases evaporation

ofsurface water through the stomata of theleaves and decreases

the moisture contentof the soil,Increasein UV radiations damage paints and fbres, causing them to fade faster.

9.6 Organic Chemistry

photosynthesis stops but the plants continue

9.9 WATER POLLUTION Pollution of water originates from human activities. Through different paths, pollution reaches surface or ground water 1. Easily identified source or place of pollution is called as

point source, e.g., municipal and industrial disclharge pipes where pollutants enter the water-source. 2. Non-point sources of pollution are those where a source of pollution cannot be easily identified, e.g, agricultural run off (from farm, animals and crop-lands), acid rain, storm-water drainage (from streets, parking lots and lawms) etc. (Table 9.1). Table 9.1 Major water pollutants

Pollutant

Source

Microorganisms

Domestic sewage

Organic ater

Domestic sewage, animal excreta and waste, decaying animals and plants,

discharge from food processing factories Plant nutrients

Chemical fertilizers

Toxic heavy metals Industries and chemical factories Erosion of soil by agriculture and strip Sediments

mining Pesticides

Chemicals used for killing insects, fungi and weeds

Radioactive substances

Heat

Mining of uranium containing minerals Water used for

cooling in industries

9.9.1 CAUSES OF WATER POLLUTION 1. Pathogens: The most serious water pollutants are the disease causing agents called pathogens. Pathogens include bacteria and other organisms that enter water from domestic sewage and animal excreta. Human excreta contain bacteria such as Escherichia coli and Streptococcus faecalis which cause gastrointestinal discases. 2. Organic wastes: The other major water pollutant is organic matter such as leaves, grass, trash etc. They pollute water as a consequence of run off. Excessive phytoplankton growth within water is also a cause of water pollution. These wastes are biodegradable. The large population of bacteria decomposes organic matter present in water. They consume oxygen dissolved in water. The amount of oxygen that water can hold in the

solution is limited. In cold water, dissolved oxygen (DO) can reach a concentration up to 10 ppm (parts per million), whereas oxygen in air is about 200,000 ppm. That is why even a moderate amount of organic matter when decomposes

in water can deplete the water of its dissolved oxygen. The concentration of dissolved oxygen in water is very important for adequate life. If the concentration of dissolved oxygen

of water is below 6 ppm, the growth of fish gets inhibited. 3. Oxygen reaches water either through atmosphere or from the process of photosynthesis carried out by many aquatic green

plants during day light. However, during night,

resulting in reduction of dissolved oxygen. The dioes

oxygen is also used by microorganis

to

matter.

4.

If too much of organic available oxygen is used

ssolved oxidize organiç

matter is added to water up. This causes oxygen

denee

aquatic life to die. Thus, anaerobic bacteria (which

require oxygen) begin to break down the organic wao foul smell and are human health. Aerobic (oxygen requiring) bacteria demful to these organic wastes and keep the water depleted in dise

produce chemicals that have a

ssolved

oxygen. The amount the organic matter

of oxygen required by bacteria to breakdown

present in a certain volume of a saml is called Biochemical of water, Oxygen Demand (BOD The amount of BOD in the water is a measure of the amount of organic material in the water, in terms of h much oxygen will be required to break it down biological

Clean water would have BOD value of less than 5 highly polluted water could have a BOD value af

whereas

17 ppm or more.

5. Chemical pollutants: Water is an excellent solvent, water soluble inorganic chemicals that include heavy metals such as Cd, Hg, Ni etc. constitute an important class of pollutants. All these metals are dangerous to humans because our body cannot excrete them. a. These metals then can damage kidneys, central nervous system, liver etc. Acids (like sulphuric acid) from mine drainage and salts from many different sources including raw salt used to melt snow and ice in the colder climates (sodium and calcium chloride) are water soluble chemical

pollutants. b. The organic chemicals are another group of substances

that are found in polluted water. Petroleum products many sources of water e.g., major oil spils n

pollute

Oceans.

Other organic substances with serious impacts are the

pesticides

that drift down from sprays

or

runoff from

lands.

Various industrial chemicals like polychlorinated biphenyls, (PCBs) which are used as cleansing solvent. detergents and fertilizers add to the list of water pollutants. PCBs are suspected to be carcinogenic. Nowadays mst

of the detergents available are biodegradable. However use can create other problems. The bactera

their

responsible for degrading biodegradable detergent teeu it and grow rapidly. While growing. they may use u

on

ofoxygen Ki

all the oxygen dissolved in water. The lack all other forms of aquatic life such as fish and

plants

Fertilizers contain phosphates as additives. addition of phosphates in water enhances algae gro Such profuse growth of algae, covers the water sura leads and reduces the oxygen concentration in water. This tion of to anaerobic conditions, commmonly with accumul sted

abnoxious decay and animal death. Thus, bloom-intesthe water inhibits the growth of other living organisims

water body.

Environmental Chemistry

nutrient enriched water bodie which kills animal life dense plant population, results in subsequent loss and it of oxygen in which

rocess

This

nort a

Suppor

9.10 SOIL POLLUTION Soil is the uppermost part of the earth's crust and is formed as a

by depriving

15 known as

of biodiversity

result of decomposition and disintegration of surface rocks due

Eutrophication.

to weathering over a very long period of time.

INTERNATIONAL

It is the soil which provides nutrients, water and minerals

STANDARDS FOR DRINKING

tor the growth of the plants. It is, in fact, the heart of biosphere. However, large-scale cutting of trees, digging of minerals, industries and 1ncreasing brick-kilns, poisonous effluents of the

g9.2 WATER

Standards for

tational kthey .

must be

drinking

below

given

use of

aumping of toxic and harmful wastes, increase in the automobiles etc. are damaging the quality of the soil and resulting into soil pollution.

water should be tested

deficiency in drinking

Cconcentration. lts

jon

water are

followed.

purposes, tuoride: For drinking

ior F

water

diseases such as tooth decay water to f Soluble fiuoride is often added to drinking The Fo concentration up to I ppm or I mg dm3. hring its the enamel on teeth much harder by converting ions make [5(Ca,(PO,),.Ca(OH),], the enamel on

e harmful to man and

causes

hydroxylapatite,

of the teeth, into much harder fluorapatite, the surface Fo ion concentration above 3(Ca (PO.Cak2]. However, of teeth. At the same time, brown mottling 2 ppm causes 10 ppm) causes harful effect to bones fluoride

(over

excess and teeth.

water gets contaminated with Pb when Pb 2. Lead: Drinking of water. The upper limit pipes are used for transportation Pb concentration of lead in drinking water is about 50 ppb.

etc. damage kidney, liver, reproductive system in drinking 3. Sulphate: Excessive SO4ions (>500 ppm) can

water causes laxative effect.

is

of NO in drinking 4. Nitrate: The maximum limit water can cause disease S0 ppm. Excess nitrate in drinking water

such

as

baby' syndrome).

methemoglobinemia ("blue

concentration of 5. Other metals: The maximum in drinking water are Common metals recommended

some

given

in Table 9.2. 2ble 9.2 Maximum

prescribed

concentration of

some

metals in

9.10.1

Maximum

concentration

(ppm

or

mg

1.

Organic

re

Cu

of fallen trees

animals leaves etc. and also from the remains of dead

and their excreta. These materials are decomposed by convert them into microorganisms present in the soil and has all those Humus humus (process is called humification). excellent properties which are an urgent need of the plants.

of different 2. Mineral matter: It comprises mineral particles formed by its sizes which originate from the rock and are fine as gravel, coarse sand, are

disintegration. They sand, slit and clay.

solvent for

transporting agent by carrying from the soil to different parts of the plant.

and also acts as a

bacteria, protozoa 4. Biological system: It consists of algae, of organic matter etc. which help in the decomposition present in the soil. 5. Soil air: It is present in the pores of the soil i.e. the space It contains more of C0, and the soil between

particles.

moisture than O,. It is needed for soil microorganism and underground parts of the plants.

LOAM SoIL

The soil containing almost equal amounts of sand, slit and clay

3.0

alongwith humus and 34%% air and 66% water is considered to the best soil for most of the crops. lt is called loam soil.

0.005

Zn

5.0

9.10.3

SoURCES OF SoIL POLLUTION

Some of the main sources of soil pollution are brietly described

below:

POLLUTION .9.3 PREVENTION OF WATER not

dump

waste

into

directly pond, stream or lake.

which

can enter

compost instead

*Avoid the

use

and try to use Add a Or

nutrients

0.2

Cd

2.

present

acts as a 3. Soil water: The water present in the soil for the plants needed materials various organic and inorganic

9.10.2

0.2

D

a result present in the soil as as roots, such and mixing of their parts

matter: This is

dm)

0.05

Mn

CoMPOSITION OF THE SOIL

The main components of the soil are as follows:

drinking water

Metal

9.7

few

a

household

to any

water

of chemical

dried

neem

industrial drain

1. Urban wastes: Urban waste consists of soil refuse

such as, river,

containing garbage and rubbish material like paper pieces,

in gardens.

of vegetables and

body,

fertilizers

pesticides like DDT,

of

or

insects away.

permanganate

(KMnO4)

crystals of potassium house. tank of your

bleaching powder

to the

poisonous gases, toxic hydrocarbons and microbes (bacteria) which cause diseases.

out

at home malathion etc.,

leaves to help keep

water

glass, plastics, used cans, leaves, polythene bags, peelings fruits, food wastes etc. These wastes emit

2.

Industrial wastes: Industrial waste of toxic and disastrous chemicals

pathogenic

contains huge amounts

many of which

are non-

9.8 Organic Chemistry of the greatest sources of radioactive pollution of th Nuclear tests produce nuclear dust in the atmospher

biodegradable. Some of the industries responsible for soil

pollution are paper and pulp mills, sugar mills, textiles, chemical industries, distilleries, metal processing industries,

ultimately falls into the soil and pollutes it. The use oe.ich and hydrogen bombs in the wars produces radioie nuclides as the by-products. All the radioactive produced emit radiations which are disastrous for t thus

mining, cement and glass industries, petroleum industry etc. 3.

wasto

Agricultural pollutants: The use of fertilizers. pesticides

soil conditioners, fumigants etc. have increased the yield from the crops but they have polluted the soil. Their entry into food chain has adversely affected the health of the human beings and led to a number of diseases. Some of the agricultural polutants are briefly described

life

on the earth.

6. Farm wastes: These are one of the biggest sources of s. pollution. In small towns and rural areas, there has soil increase in dairies, poultries and piggery farms. been

The.

slurry of the land. This may. eir the soil and through pollute the ground water. If their seep wast (faecal matter) is dumped, it may become a breeding Dlaca washings collect as a

below: a. Fertilizers: Fertilizers act as nutrients for plant but if nitrates and phosphates are present in excess, they have

wet

for insects. Moreover, their waste may contain pathogeni bacteria and virsues which may enter the plant and then pase on to humans.

hazardous effects. b. Pesticides: These are the chemicals that are used to kill or

stop the growth of unwanted organisms. They adversely affect the health of human beings. These are further

classified into the following different categories.

9.11SOME DEVELOPMENTS ABOUT WASTE RECYCLING

i. Herbicides: These are the compounds used to

control weeds. Earlier inorganic compounds, namely, sodium chlorate (NaC10,) and sodium arsenite (Na,AsO,) were commonly used as herbicides but arsenic compounds, being toxic to mammals, are no

longer preferred. Instead, organic compounds such as triazines, are now considered as better herbicides especially for the corn-fields. i. Insecticides: These are the chemicals that are used to kill the insects which destroy the crop. They also help to control malaria and yellow fever. The most common insecticides in use since 1950 are the

chlorinated hydrocarbons like DDT (dichlorodiphneyl trichloroethane), BHC (benzene hexachloride), etc. As they are not much soluble in water, they stay in the soil for long time and are absorbed by the soil and contaminate root crops like raddish, carrot etc. Anew series ofproducts, namely, organophosphates and carbamates have been introduced. These are more biodegradable. But these chemicals are nerve toxins and hence more harmful to humans and have caused even deaths. Thus, insecticide industry is engaged in developing new insecticides. ii. Fungicides: These are the chemicals used to stop the

Due to recent developments made in chemical and textile

industries, clothes will be made from recycled plastic waste. These will be available soon in the global textile market. Fuel obtained from plastic waste has high octane rating t contains no lead and is known as "green fuel". Technology has now been developed to produce electricity from the garbage. A pilot plant has been set up, where after removing ferrous metal, plastic, glass, paper etc. from garbage. it is mixed with water. It is then cultured with bacterial species for producing methane, commonly known as biogas. The remaining

product is used as manure and biogas is used to produce electricity

9.12 STRATEGIES TO CONTROL

ENVIRONMENTAL POLLUTION There are two main sources of waste in the environment causing

pollution. These are (1). Household waste and (2). Industrial waste. 1. Management of household waste: Domestie wastes

after collection

the plants which do not contain chlorophyll, therefore

thay cannot use solar energy for the synthesis of their

of the main plant is retarded. Organo-mercury compounds are the most common fungicides. However, their dissociation in the soil produces mercury which is highly toxic and proves fatal if it enters into grain. 4. Soil conditioners: These are used to protect the soil

carried to the

disposable

where

site,

materials. Biodegradable wastes are deposited in land fills and converted into compost. Non-biodegradable waste e.g., plastic, metal scraps. gl

growth of fungi and check plant diseases. As fungi are

food (carbohydrates). Hence, they depend upon other plants and living organisms. As a result, the growth

are

it is separated into biodegradable and non-biodegradable

etc., are sent for recycling. 2.

Management of industrial waste: Biodegradable wastes are generated by cotton paper, textile and food processing industries. Non-biodegradable wastes are produced by the following industries: a. Chemicals, drug, pharmaceutical, dyes, pesticides, rnudoc goods ete., industries produce inflammable waste.

fertility

but contain several toxic metals like Pb,As, Hg, Cd, Co ete. which may enter into the food chain.

5. Radioactive pollutants: Dumping of the nuclear wastes from the nuclear power plants into the soil has been one

b. Fertilizer industries produce gypsums. . Thermal power plants produce fly ash.

like, Fe, Al, Cu, Zn and steel produce mud, tailings and blast furnaces slag.

d. Metal industries

pla

EnvironmentalChemistry

methods that are usually employed for properly n g e m e n to fw a s t e s

are:

line: It is used for glass, iron scrap, plastic wastes,

9.13.2

9.9

METHODS USED IN GREEN CHEMISTRY

In Green chemistry mild and environmental friendly reagents are

Recyc

making papers.

for and L--days fly ash and slag from the steel industry are

keed by the cement imdustry. Larger quantities of toxic

r e destroyed by controlled incineration whereas N uantities are burnt along with factory garbage in open

used, e.g., Sunlight, microwave, sound waves and enzymes. 1. Use of sunlight and microwaves: The use of sunlight and ultraviolet light in chemical reactions is called

Photochemistry. In photochemical reactions sometimes the products are such that they cannot be obtained by usual chemical methods. In these reactions no toxic solvents are used but only the reactants in proper ratios are mixed on a solid support such as alumina and exposed to microwaves. The reaction is complete within minutes and yields are also higher.

bins.

. Burning and

incineration: Some combustible waste

materials such as dried plant leaves etc. can be burnt to get the heat energy.

Many combustible wastes including household wastes, chemical wastes and biological wastes e.g. from hospitals which occupy large volume can be incinerated, i.e., reduced 1o ash which can be used as a land-filing materials. This is

one of the best methods for the disposal of polychlorinated biphenyl (PCBs) as the high temperature produced breaks the C-Cl bonds. But incomplete combustion of PCBs results in the production of highly toxic chloro compounds. Moreover, the ash produced consists of very fine particles which can enter into lungs and cause serious problenms. 3. Digesting: This method is used to degrade a number of toxic organic wastes. The method consists in degrading the waste by microorganisms in the absence of oxygen (called anaerobic digestion). The main products formed are CO, and CH4

2. Use of sound waves: The branch of chemistry in which sound waves are used in chemical reactions is called Sonochemistry. Efforts are being made to develop conditions to achieve the desired results. 3. Use of enzymes: Enzymes are environmental friendly reagents and they work at ambient temperature in aqueous solutions since water has high specific heat and low volatility. Water is cost effective, non-inflammable and devoid of any carcinogenic effects. By using enzymes many biochemical methods have been developed to prepare precursors and intermediates of certain medicines and antibiotics. For

exmaple, semi-synthetic pencillins such as amphicillin and amoxycillin have been prepared using enzymes.

2[CH,O]>CO.(g)+CH,(g)

If reactants are fully converted into useful environmental

Methane can be used as a fuel.

friendly products by using environmental friendly medium then there would be no chemical pollutants introduced in

4. Sewage treatment: The sewage is treated as a. Large size materials are filtered through screens. They

the environment.

are then used to fill low lying land. b. It is allowed to stand in tanks. As a result, many solids while oils and grease float settle down

9.13.3

NoBEL LAUREATES IN GREEN CHEMISTRY AND METATHESIS

(called sludge)

on the surface from where they can be skinned off. C.The organic materials present in it are allowed to undergo

d.

mierobial oxidation. for the removal Finally, the waste water is suitably treated filteration and of phosphate followed by coagulation,

disinfecting it by adding chlorine.

into land because it

Dumping: Sewage sludge is dumped and phosphorus, which COntains compounds of nitrogen

act

as a good fertilizer for the soil.

9.13 GREEN CHEMISTRY One way to

ct protect

our

environment

effluents and from chemical

Chauvin, Institute Francais du Petrole, Ruell-Malmaison France, Robert H. Grubbs, California Institute of Technology (Caltech), Pasadena, CA, USA and Richard R. Schrock, Massachusetts Institute of Technology (MIT). Cambridge, MA.

Yves

USA won the 2005 Nobel Prize in chemistry for work that reduced hazardous waste in creating new chemicals. The trio won the award for their development of the metathesis method in

synthesis

revolutionary environmentally-friendlier polymers. This

9.13.1 DEFINITION

Green chemistry is producing ry

tovSuch

Toxico-

chemicals

life needs of our daily neither use which

chemical processes reactions and atmosphere. into the such chemicals

n e m i c a l s nor

emit

organic

way to rearrange groups of atoms within molecules

that the Royal Swedish Academy of Sciences likened to a dance in which couples change partners. The metathesis has tremendous commercial potential in the pharmaceuticals, biotechnology and food stuffs production industries. It is also used in the development of

2Sse is to use Green Chemistry.

a

represents a great step forward

for

'green chemistryy reducing potentially hazardous waste through smarter production. Metathesis is an example of how important of basic application science is for the benefit of man, society and the environment.

9.10

Organic Chemistry

9.14.3

9.14 GREEN CHEMISTRY

prepared by (CH,CHO) is now commercially the presence of ionic catalyst in step oxidation of ethene in aqueous of 90%.

medium with

DRY CLEANING OF CLOTHES was

earlier used

gives

These days, used earlier for bleaching paper. which promotes suitable catalyst, with hydrogen peroxide (H,O,) used. is peroxide, the bleaching action of hydrogen

CH,CH0 (90%)

Green chemistry, in a nutshell, is a cost-effective approach in materials, energy which involves reduction

consumption aand

waste regeneration.

9.15

BLEACHING OF PAPER was

yield

Catalyst

SOME SUGGESTIONS FOR REDUCINGPOLLUTION

1. Set up

Chlorine gas

an

CH, - CH2 +0,Paycullinwaten)

solvent for dry water and is also

as

Tetra chloroethene (Cl,C-CCi,) contaminates the ground cleaning. The compound this compound is now The process using a suspected carcinogen. with where liquetied carbondioxide, solvent being replaced by a process, is used. Replacement of halogenated a suitable detergent water in less harm to ground by liquid CO, will result is used for the In these days hydrogen peroxide (H,0,) which clothes in the process of laundary, purpose of bleaching water. of amount use of lesser better results and makes

9.14.2

One

Ethanal

IN DAY-TO-DAY LIFE 9.14.1

SYNTHESIS OF CHEMICALS

2.

a

home and use it th to reduce to the use of fertilizer

compost tin in your garden

or

produce manure for plants and use cloth bags. Avoid plastic carry bags

aluminium and other items should he 3. Newspapers, glass

stored for recycling.

Exercises 12. Which one ofthe following statement regarding photochemi-

Answer Type

Correct.

cal smog is not correct?

ngle

() Photochemical smog is formed through photochemical

arctica, ozone lepletion is due to the formation of the

reaction involving solar energy. following compound:

and SO, 8) SO, the Pick up

(2) Photochemical

(2) Peroxy acetyl nitrate

( 1 )A c r o l e i n

correct

smog fraction. in character.

(4) Photochemical smog is an oxidizing agent Which one of the following statement is not true? carbon are the (1) Oxides of sulphur, nitrogen and

combustion of fuels in automobiles plays a major role in photochemical smog. Classical smog has an oxid1zing character while the

13.

5.5 and 9.5.

(2) pH of drinking water should be between for the growth (3) Concentration of D0 below 6 ppm is good of fish. less than 5

atmosphere goes down. 14.

lung cancer' is caused by

)

(4) Paper

Textiles

4. Which of the following has greatest affinity for haemoglobin? 1) CO

(2) NO

)0

(4) CO

ppm. (4) Clean water would have a BOD value of of formation the in involved not is Which of the following photochemical smog? (1) NO

(2) O

(3) CH,

(4) SO

15. Depletion of ozone layer causes

(2) Lung cancer

(1) Blood cancer (3) Skin cancer 16. Which one of the

. London smog is found in 1) Summer during day time

(4) Breast cancer

following

3) Winter during morning time (4) Winter during day time 6. Which of the following is the uppermost region of the

atmosphere?

(1) Stratosphere

(2) Troposphere

3) Exosphere

(4) Ionosphere

(1) Polyhalogens

(2) Ferrocene

(3) Fullerenes

(4) Freons

(2) 100-500 nm (3) 500-1000 nm (4) 100010,000 nm 19. Which of the following is the coldest region?

of

20. The aromatic compounds present as particulates are

(2)0, and N

(3) Nitrobenzene 21. Which of the

(3) Oxides of sulphur and nitrogen

of the following is a

secondary pollutant?

(1) CO

Ozone in the stratosphere is deleted by

(2) CF16 (4) CF storage tank

Bhopal gas tragedy (1) Ammonia

plant in

(3) Methylisocyanate

of the

(2) Toluene (4) Polycyclic hydrocarbons

following is not a greenhouse gas? (2) CH

(1) CO (3) Chlorofluorocarbons

(4)0

22. Which of the following is true about (1) It is reducing in nature (2) It is formed in winter (3) It is a mixture of smoke and

(2) N,O (4) PAN

(3) SO

(2) Mesosphere (4) Thermosphere

(1) Troposphere (3) Stratosphere (1) Benzene

(4)0, and N,

(2) Stratosphere (4) Exosphere

(1) Troposplhere

(1)0, and 0

a

depletion of

(1)5-100nm

(5) London smog is formed in winter 4) London smog causes bronchitis the 6.Thesmog is essentially caused by presence

leaked from

for

17. Ozone layer is present in

(3) Mesosphere

(1) London smog is oxidizing in nature (2) London smog contains H,SO, droplets

n e gas

responsible

18. The size of particulates of H,SO, fog lies in the range

1. Which of the following statement is false?

(1) CF,CL, 3) CHCs

is

the ozone layer in the upper strata of the atmosphere?

(2) Summer during morning time

Which

most

widespread air pollutant.

photochemical smog is reducing in character. Photochenmical smog occurs in day time whereas the classical smog occurs in the moming hours. of smog the level of ozone in the 4 During formation

(2) Silica

irritation in eyes

(3) Carbon monoxide does not play any role in photochemical

statement?

(1) Asbestos

cause

and throat.

(4) Chlorine nitrate

ncO which is a major pollutant resulting from the

White

smog does not

Union Carbide

was:

(2) Phosgene (4) Methylamine

(4)

It causes irritation in 23. The most abundant

(1) Methane (3) Propane

photochemical smog?

fog

eyes

hydrocarbon pollutant is (2) Ethane

4) Butane

9.12 Organic Chemistry

(2) CO, can absorb infrared radiations but does

24. Which of the following is not considered to be a pollutant?

(2) CO,

(1) NO,

(4) CH,

(3) 0 25.

Which of the

following is present in

(3) HCI

Numerical Value Type 1. How many of the following compounds are gaseos ous a pollutants? (I1) NO (1) CO

26. BOD, is (1) Waste decomposed in 5 days (2) Oxygen used in 5 days (3) Microorganisms killed in 5 days (4) Dissolved oxygen left after 5 days 27. ldentify the wrong statement among the following. Chlorofluorocarbons are

depletion. Green house effect is

(2) (3)

Ozone

(4) Acid rain contains mainly HNO,

maximum amount in

(2) H,SO (4) H,CO

(1) HNO

responsible for

ozone

layer

mostly

nitrogen

(VIII) O,

(11) CO

() Co (I) CH

radiation from the

because of oxides of

(V) H,S

(X) Smoke (IX) Fumes 2. How many gases are responsible for green house effec

sun to reach the earth. is

(IV) CO

(11) NO, (V) SO (VII) SO

responsible for global warming.

layer does not permit infrared

(4) Acid rain

andd

(TV) N,O (VI) NO,

(V) NO

(VI) Chloroflurocarbons (CFCs)

sulphur. 28. Smog is essentially caused (1) 0, and N,

by the presence of

(LX) Water vapours

(VIII) O,

(X) SO

(2) 0, and N, (3) Oxides of sulphur and N,

3.

How many gaseous species are present

29. When rain is accompanied by a thunderstorm, rain water will have a pH value

TV) NO®

(I) O,®

(V) Atoms of C (VIID) Atoms of N

(v) N,

air

(VI) o®

X)Atoms of O

(X) Atoms of S 4.

there

How many acids

are

present in acid rain?

(II) HCI0

1)H,CO (III) H,SO

by occurrence of thunderstorm

(IV) HNO, (VD H,P0,

(V) HCI

Multiple Correct Answers Type 1. The ozone layer is depleted by (1) NO

(2) SO,

(3) CH,

(4) CFCs

2. The gases involved in the formation of photochemical smog

3.

(d) CO

(2) SO

(3) NO

(4) Hydrocarbons

Choose the wrong statements:

(1)

(VI) CH,coOH 5.

The co-existence

CO,

is

responsible for greenhouse effect.

of biotic components and

components is called

an

(1) Micro-organisms

(V)N (VII) P

(XI) Carbohydrates (XII) Humidity

abiou

many or u ecosystem. How

following are abiotic components?

(I1) Plants

are

mesosphere and

(LI) O,2

the collected

in (1) Which depends upon the amount of dust when rain water is without that than lower (2) Slightly thunderstorm thunderstorm is not (3) Slightly higher than that when the

(4)

in

thermosphere?

(4) 0, and Og

Uninfluenced

not allow

(3) NO is more harmful than NO,

acid rain?

(1)

them to pass through.

(I1) Animals

(IV) co (VI) S (V) Proteins (X) Temperature

ArchivesS (2) Phosgene (4) Methylamine

(1) Ammonia

EMAIN

do

Correct

Answer

one of the Which one

(3) Methylisocyanate

Type

(JEE Main 2013)

following statements in not true?

xides of sulphur, nitrogen and carbon are the most

( )Orid

widespread air pollutant. ( p)pH

)

ofdrinking

Concentration

growth of fish.

( 4 ) Clean water

should be between 5.5 and 9.5. of DO below 6 ppm is good for the ater

would have a BOD value of less than 5

4.

The concentration of fluoride, lead, nitrate and iron in a water sample from an underground lake was found to be 1000 ppm, 40 ppm, 100 ppm and 0.2 ppm, respectively. This water is unsuitable for drinking due to high concentration of: (1) Lead

(2) Nitrate

(3) Iron

(4) Flouride

(JEE Main 2016)

Ppm

(AIEEE 2011) , Which one of the following statements regarding photo

smog is not correct?

chemical

5. A water sample has ppm level concentration of following anions F=10; S 0 = 100; NO = 150

The anion/anions that makes/make the water sample

) Photochemical smog is formed through photochemical

unsuitable for drinking is/are:

reaction involving solar energy.

2) Photochemical smog does not cause irritation in eyes and throat. 3) Carbon monoxide

does

not

play

any

role

and NO (2) Only F 4) Only NO (3) Only S02 (JEE Main 2017)

in

photochemical smog fraction. (4) Photochemical smog is an oxidizing agent in character.

(AIEEE 2012) 3. The gas leaked from a storage tank of the Union Carbide

plant in Bhopal gas tragedy was:

(1) Both S0

6. The recommended concentration in drinking water is upto 1 ppm

of fuoride as

On

fuoride ion is

required to make teeth enamel harder by converting

[3Ca,(PO,),Ca(OH),]to: (1) [CaF]

(2) [3(CaF,).Ca(OH),]

(3) [3Ca,(PO,),CaF]

(4) [3(CaF>).Ca(OH),] (JEE Main 2018)

Answers Key Numerical Value Type

EXERCISES

1. (8)

Single Correct Answer Type 3. (3) (4) 2. (3) 6. (3) 8. (3) 7. (1) 1. (3) 13. (3) 12. (2) l6. (4) 17. (2) 18. (3) 21. 4) 22. (4) 23. (1) 26. (2) 27. (3) 28. (3)

4. (2)

5. (3)

9. (4) 14. (4)

10. (1)

19. (2)

20. (4)

24. (2)

25. (2)

29. (2)

Multiple Correct Answers Type 1. (1,4)

2. (3, 4)

3. (3, 4)

2.

(6)

3. (6)

4. (3)

5. (8)

4. (2)

5.(2)

ARCHIVES JEE Main

15. (3)

Single Correct Answèr Type 1. (3) 6. (3)

2. (2)

3. (3)