Preview A Complete Resource Book in Chemistry for JEE Main 2019 by Atul Singhal (2018)

About Pearson
Pearson is the world’s learning company, with presence across 70 countries
worldwide. Our unique insights and world-class expertise comes from a long
history of working closely with renowned teachers, authors and thought
leaders, as a result of which, we have emerged as the preferred choice for
millions of teachers and learners across the world.
We believe learning opens up opportunities, creates fulfilling careers and
hence better lives. We hence collaborate with the best of minds to deliver
you class-leading products, spread across the Higher Education and K12
spectrum.
Superior learning experience and improved outcomes are at the heart of
everything we do. This product is the result of one such effort.
Your feedback plays a critical role in the evolution of our products and you
can contact us at We look forward to it.

A01_KUMAR_0283_01_SE_PREL.indd 1

5/10/2017 11:19:37 AM


This page is intentionally left blank

A01_KUMAR_0283_01_SE_PREL.indd 2

5/10/2017 11:19:37 AM


A Complete Resource Book in

chemistry

for

JEE Main 2019
A.K. Singhal
U.K. Singhal


Dedicated to
my grandparents,
parents and teachers

Copyright © 2018 Pearson India Education Services Pvt. Ltd
Published by Pearson India Education Services Pvt. Ltd, CIN: U72200TN2005PTC057128.
No part of this eBook may be used or reproduced in any manner whatsoever without the publisher’s
prior written consent.
This eBook may or may not include all assets that were part of the print version. The publisher
reserves the right to remove any material in this eBook at any time.
ISBN: 9789353062156
eISBN: 9789353063412

Head Office:15th Floor, Tower-B, World Trade Tower, Plot No. 1, Block-C, Sector-16, Noida 201 301,
Uttar Pradesh, India.
Registered Office: 4th Floor, Software Block, Elnet Software City, TS-140, Block 2 & 9,
Rajiv Gandhi Salai, Taramani, Chennai 600 113, Tamil Nadu, India.
Fax:  080-30461003, Phone: 080-30461060
Website: in.pearson.com, Email: 

A01_KUMAR_0283_01_SE_PREL.indd 4

5/10/2017 11:19:38 AM

Contents
Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . viii
JEE Mains 2018 Paper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xi
JEE Mains 2017 Paper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xviii
Chapter 1

Basics of Chemistry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.1–1.32

Chapter 2

Solid State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.1–2.34

Chapter 3

Gaseous State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.1–3.36

Chapter 4

Atomic Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.1–4.38

Chapter 5

Solutions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.1–5.38

Chapter 6

Energetics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6.1–6.40

Chapter 7

Chemical Equilibrium . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.1–7.42

Chapter 8

Ionic Equilibrium . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8.1–8.54

Chapter 9

Redox Reactions and Electrochemistry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.1–9.50

Chapter 10

Chemical Kinetics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10.1–10.46

Chapter 11

Surface Chemistry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.1–11.34

Chapter 12

Periodic Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12.1–12.26

Chapter 13

Chemical Bonding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13.1–13.38

Chapter 14

Chemistry of Representive Elements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14.1–14.26

Chapter 15

Chemistry of Non-Metals I . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15.1–15.30

Chapter 16

Chemistry of Non-Metals II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16.1–16.60

Chapter 17

Chemistry of Lighter Elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17.1–17.28

Chapter 18

Chemistry of Heavier Elements (Metallurgy) . . . . . . . . . . . . . . . . . . . . . . . . . . . 18.1–18.34

Chapter 19

Transition Metals Including Lanthanides and Actinides . . . . . . . . . . . . . . . . . . . . . 19.1–19.26

Chapter 20

Coordination Compounds . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20.1–20.40

Chapter 21

Nuclear Chemistry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21.1–21.28

Chapter 22

Purification and Characterization of Carbon Compounds . . . . . . . . . . . . . . . . . . . . 22.1–22.26

A01_KUMAR_0283_01_SE_PREL.indd 5

5/10/2017 11:19:38 AM


vi    Contents
Chapter 23

General Organic Chemistry I�������������������������������������������������������������������������������������������������������� 23.1–23.54

Chapter 24

General Organic Chemistry II������������������������������������������������������������������������������������������������������ 24.1–24.52

Chapter 25

Hydrocarbons and Petroleum ����������������������������������������������������������������������������������������������������� 25.1–25.58

Chapter 26

Organic Compounds with Functional Groups Containing Halogens (X)�������������������������������������� 26.1–26.36

Chapter 27

Alcohol Phenol Ether�������������������������������������������������������������������������������������������������������������������� 27.1–27.56

Chapter 28

Organic Compounds Containing Oxygen-II�������������������������������������������������������������������������������� 28.1–28.70

Chapter 29

Organic Compounds with Functional Groups Containing Nitrogen�������������������������������������������� 29.1–29.44

Chapter 30

Polymers�������������������������������������������������������������������������������������������������������������������������������������� 30.1–30.20

Chapter 31

Biomolecules and Biological Processes�������������������������������������������������������������������������������������� 31.1–31.40

Chapter 32

Chemistry in Everyday Life ��������������������������������������������������������������������������������������������������������� 32.1–32.22

Chapter 33

Environment Chemistry��������������������������������������������������������������������������������������������������������������� 33.1–33.16

Chapter 34

Practical Chemistry��������������������������������������������������������������������������������������������������������������������� 34.1–34.34

Appendix �������������������������������������������������������������������������������������������������������������������������������������������������������������� 35.1–35.20

Mock Test 1

�����������������������������������������������������������������������������������������������������������������������������������������������������M1.1–M1.6

Mock Test 2

�����������������������������������������������������������������������������������������������������������������������������������������������������M2.1–M2.6

Mock Test 3

�����������������������������������������������������������������������������������������������������������������������������������������������������M3.1–M3.6

Mock Test 4

�����������������������������������������������������������������������������������������������������������������������������������������������������M4.1–M4.6

Mock Test 5

�����������������������������������������������������������������������������������������������������������������������������������������������������M5.1–M5.6

A01_KUMAR_0283_01_SE_PREL.indd 6

5/10/2017 11:19:38 AM


Preface
About the Series
A Complete Resource Book for JEE Main series is a must-have resource for students preparing for JEE Main examination.
There are three separate books on Physics, Chemistry, and Mathematics; the main objective of this series is to strengthen
the fundamental concepts and prepare students for various engineering entrance examinations. It provides class-tested

course material and numerical applications that will supplement any ready material available as student resource.
To ensure high level of accuracy and practicality, this series has been authored by highly qualified and experienced
faculties for all three titles.
About the Book
A Complete Resource Book in Chemistry for JEE Main 2018 is an authentic book for all the aspirants preparing for the
joint entrance examination (JEE). This title is designed as per the latest JEE Main syllabus, where the important topics
are covered in 34 chapters. It has been structured in user friendly approach such that each chapter begins with topic-wise
theory, followed by sufficient solved examples and then practice questions.
The chapter end exercises are structured in line with JEE questions; with ample number of questions on single choice
correct question (SCQ), multiple-type correct questions (MCQ), assertion and reasoning, column matching, passage based
and integer type questions are included for extensive practice. Previous 15 years’ questions of JEE Main and AIEEE are also
added in every chapter. Hints and Solutions at the end of every chapter will help the students to evaluate their concepts and
numerical applications. Because of its comprehensive and in-depth approach, it will be especially helpful for those students
who prefers self-study than going for any classroom teaching.
Series Features
•
•
•
•
•
•

Complete coverage of topics along with ample number of solved examples.
Large variety of practice problems with complete solutions.
Chapter-wise Previous 15 years’ AIEEE/JEE Main questions.
Fully solved JEE Main 2017 questions.
5 Mock Tests based on JEE Main pattern in the book.
5 Free Online Mock Tests as per the recent JEE Main pattern.

Despite of our best efforts, some errors may have crept into the book. Constructive comments and suggestions to

further improve the book are welcome and shall be acknowledged gratefully. Kindly share your feedback with me at
or

A.K. Singhal

A01_KUMAR_0283_01_SE_PREL.indd 7

5/10/2017 11:19:38 AM


Acknowledgements
The contentment and ecstasy that accompany the successful completion of any work would remain essentially incomplete
if I fail to mention the people whose constant guidance and support has encouraged me.
I am grateful to all my reverend teachers, especially, late J.K. Mishra, D.K. Rastogi, late A.K. Rastogi and my honourable guide, S.K. Agarwala. Their knowledge and wisdom has continued to assist me to present in this work.
I am thankful to my colleagues and friends, Deepak Bhatia, Vikas Kaushik, A.R. Khan, Vipul Agarwal, Ankit Arora
(ASO Motion, Kota), Manoj Singhal, Yogesh Sharma, (Director, AVI), Vijay Arora, (Director, Dronacharya), Rajneesh
Shukla (Allen, Kota), Anupam Srivastav, Rajeev Jain (M V N), Sandeep Singhal, Chandan Kumar (Mentor, Patna),
P.S. Rana (Vidya Mandir, Faridabad).
I am indebted to my father, B.K. Singhal, mother Usha Singhal, brothers, Amit Singhal and Katar Singh, and sister,
Ambika, who have been my motivation at every step. Their never-ending affection has provided me with moral support and
encouragement while writing this book.
Last but not the least, I wish to express my deepest gratitude to my wife Urmila and my little, —but witty beyond her
years, daughters Khushi and Shanvi who always supported me during my work.

A.K. Singhal

A01_KUMAR_0283_01_SE_PREL.indd 8

5/10/2017 11:19:38 AM

Chemistry Trend Analysis
(2007 to 2018)
S. No

Chapters

07

08

09

10

11

12

13

14

15

16

17

18

1

Basics of Chemistry

3

–

–

–

–

1

1

–

1

–

2

2

2

Solid State

–

1

1

2

1

1

2

1

1

1

2

–

3

Gaseous State

1

–

–

–

1

1

1

2

1

1

1

–

4

Atomic Structure

1

2

2

2

1

1

1

1

1

1

1

–

5

Solutions

2

2

2

2

2

1

1

1

1

1

1

1

6

Energetics

3

2

3

2

1

1

1

1

1

2

2

1

7

Chemical Equilibrium

–

2

1

–

1

1

1

1

1

2

2

1

8

Ionic Equilibrium

–

2

1

3

–

1

1

–

–

–

1

3

9

Redox Reactions and
Electrochemistry

2

1

1

2

1

1

1

3

1

1

1

1

10

Chemical Kinetics

1

3

–

2

1

1

1

–

–

1

1

1

11

Surface Chemistry

–

1

1

–

1

1

1

–

2

2

1

–

12

Periodic Properties

–

–

1

1

1

1

1

1

1

1

1

–

13

Chemical Bonding

2

1

1

–

3

1

2

–

1

1

1

3

14

Chemistry of Representive
Elements

1

–

1

–

2

1

1

–

–

–

–

–

15

Chemistry of Non-Metals I

–

4

–

–

–

–

–

–

–

–

1

1

16

Chemistry of Non-Metals II

2

–

2

1

2

–

1

–

–

1

2

1

17

Chemistry of Lighter
Elements

1

–

–

–

–

1

–

–

–

1

1

1

18

Chemistry of Heavier
Elements (Metallurgy)

–

1

–

–

–

2

–

1

1

2

–

–

19

Transition Metals Including
Lanthanides and Actinides

–

1

2

–

2

–

2

–

1

1

–

–

20

Coordination Compounds

1

2

2

2

2

1

1

1

–

2

1

3

21

Nuclear Chemistry

2

–

–

–

–

–

–

1

1

–

–

–

(Continued )

A01_KUMAR_0283_01_SE_PREL.indd 9

5/18/2018 5:14:23 PM

S. No

Chapters

07

08

09

10

11

12

13

14

15

16

17

18

22

Purification and
Characterization of Carbon
Compounds

–

–

–

–

–

–

–

–

–

1

1

1

23

General Organic Chemistry I

3

2

2

1

1

1

–

–

–

1

–

–

24

General Organic Chemistry II

1

–

1

1

1

–

3

1

–

1

2

1

25

Hydrocarbons and Petroleum

3

4

1

1

1

2

1

1

1

1

1

1

26

Organic Compounds
with Functional Groups
Containing Halogens (X)

1

1

1

1

–

–

1

1

1

2

2

2

27

Alcohol Phenol Ether

–

2

1

1

2

2

1

–

1

1

2

2

28

Organic Compounds
Containing Oxygen-II

–

–

1

–

2

1

1

1

1

1

1

1

29

Organic Compounds
with Functional Groups
Containing Nitrogen

2

1

–

1

–

1

–

1

–

–

–

1

30

Polymers

–

–

1

1

–

1

–

1

–

1

1

–

31

Biomolecules and Biological
Processes

–

1

1

1

1

2

1

1

1

1

1

32

Chemistry in Everyday Life

–

–

–

–

–

1

–

1

–

1

–

–

33

Environment Chemistry

–

1

–

–

–

1

1

–

–

1

1

1

34

Practical Chemistry

1

1

–

1

–

–

–

–

1

1

1

–

Total No of Questions

33

38

30

28

30

30

29

22

21

34

35

30

A01_KUMAR_0283_01_SE_PREL.indd 10

5/18/2018 5:14:23 PM


JEE Mains 2018 Paper
1. For 1 molal aqueous solution of the following compounds, which one will show the highest freezing
point?

(A)  [Co(H 2 O)3Cl3 ].3 H 2 O

(B)  [Co(H 2 O)6 ]Cl3


(B) 

H
N

N


(C) 

(C)  [Co(H 2 O)5 Cl]Cl 2.H 2 O

H
N
⊕

2. Hydrogen peroxide oxidizes [Fe(CN)6 ]4− to [Fe(CN 6 )]3−
in acidic medium but reduces [Fe(CN)6 ]3− to
[Fe(CN)6 ]4− in alkaline medium. The other products
formed are, respectively:

(A)  H 2 O and (H 2 O + OH − )

N
H


(D) 


(C)  (H 2 O + O 2 ) and (H 2 O + OH − )
(D)  H 2 O and (H 2 O + O 2 )
3. Which of the following compounds will be suitable for
Kjeldahl’s method for nitrogen estimation?

(A) 

−

⊕

N
H

N


(C) 

4. Glucose on prolonged heating with HI gives:

(B) n-Hexane
(A)  6-iodohexanal

l-Hexene
(C) 
(D)  Hexanoic acid
5. An alkali is titrated against an acid with methyl
orange as indicator, which of the following is a correct
combination?
Acid
Strong
Strong
Strong
Strong


(III)

(IV) 

NH2

End point
Pink to colourless
Colourless to pink
Pinkish red to yellow
Yellow to pinkish red

(A)(IV) < (II) < (I) < (III)

(B) (I) < (II) < (III) < (IV)
(C) (II) < (I) < (III) < (IV)

(D) (II) < (I) < (IV) < (III)
8. Which of the following lines correctly show the temperature dependence of equilibrium constant K, for an
exothermic reaction?
ln K

A

B
1
T(K)

(0, 0)

6. The predominant form of histamine present in human
blood is (pKa, Histidine = 6.0)

(A)

H
N

C
D

⊕

NH3
N

A01_KUMAR_0283_01_SE_PREL.indd 11

NHCH3

NH

NO2

(D) 

Base
Strong
Weak
Strong
Weak

7. The increasing order of basicity of the following compounds is:

NH2
NH

(I)
(II) 

(B) 

NH2

(A)
(B)
(C)
(D)

H
N
NH2


(B)  (H 2 O + O 2 ) and H 2 O

+

⊕

NH3

(D)  [Co(H 2 O) 4 Cl 2 ]Cl .2H 2 O

N2Cl

NH2


(A)  A and D

(C)  B and C

(B)  A and B
(D)  C and D

5/18/2018 5:14:27 PM


xii    JEE Mains 2018 Paper
9. How long (approximate) should water be electrolyzed by passing through 100 amperes current so that
the oxygen released can completely burn 27.66 g of
diborane?
(Atomic weight of B = 10.8 u)

(A)  1.6 hours
(B)  6.4 hours

0.8
hours
(C) 
(D)  3.2 hours
10. Consider the following reaction and statements:
[Co(NH3 ) 4 Br2 ]+ + Br − 

→ [Co(NH3)3 Br3 ] + NH3
(I) Two isomers are produced if the reactant complex
ion is a cis-isomer.
(II) Two isomers are produced if the reactant complex
ion is a trans-isomer.
 (III) Only one isomer is produced if the reactant complex ion is a trans-isomer.
(IV) Only one isomer is produced if the reactant complex ion is a cis-isomer.
The correct statements are:

(A)  (II) and (IV)
(B)  (I) and (II)

(I)
and
(III)
(C) 
(D)  (III) and (IV)
11.

Phenol reacts with methyl chloroformate in the presence of NaOH to form product A. A reacts with Br2 to
form product B. A and B are respectively:
OH


(A) 

OH
OCH3

and

(B) 

OCH3

and

OCH3
O

O

O


(C) 

O

O
and

O

O
Br

O

O


(D) 

O

O

O
and

O
Br

12. An aqueous solution contains an unknown concentration of Ba2+. When 50 mL of a 1 M solution of Na2SO4
is added, BaSO4 just begins to precipitate. The final
volume is 500 mL. The solubility product of BaSO4 is
1 × 10-10. What is the original concentration of Ba2+?
-10

(A)  1.0 × 10 M
-9

(C)  2 × 10 M

A01_KUMAR_0283_01_SE_PREL.indd 12

14. The combustion of benzene (1) gives CO2 (g) and
H2O (l). Given that heat of combustion of benzene at

constant volume is -3263.9 kJ mol-1 at 25°C; heat of
combustion (in kJ mol-1) of benzene at constant pressure will be: (R = 8.314 JK-1 mol-1)

(A)  -3267.6

(C)  -452.46
15.

(B)  4152.6
(D)  3260

The ratio of mass percent of C and H of an organic
compound (CxHyOz) is 6 : 1. If one molecule of the
above compound (CxHyOz) contains half as much oxygen as required to burn one molecule of compound
CxHy completely to CO2 and H2O, then empirical formula of compound CxHyOz is:


(A)  C2H4O3
(C)  C2H4O


(B)  C3H6O3
(D)  C3H4O2

16. The trans-alkenes are formed by the reduction of
alkynes with:
(B)  H2-Pd/C, BaSO4
(D)  Na/liq. NH3

(A)  BCl3 and AlCl3
(C)  AlCl3 and SiCl4


OH

O

(B)  2
(4) 1

17. Which of the following are Lewis acids?

O

Br

OH


(A)  0

(C)  3


(A)  Sn-HCl
(C)  NaBH4


OCH3

Br

O

13. At 518°C the rate of decomposition of a sample of gaseous acetaldehyde initially at a pressure of 363 Torr,
was 1.00 Torr s-1 when 5% had reacted and 0.5 Torr
s-1 when 33% had reacted. The order of the ­reaction is:

(B)  PH3 and BCl3
(D)  PH3 and SiCl4

18. When metal ‘M’ is treated with NaOH, a white gelatinous precipitate ‘X’ is obtained, which is soluble in
excess of NaOH. Compound ‘X’ when heated strongly
gives an oxide which is used in chromatography as an
absorbent. The metal ‘M’ is:

(A)  Fe
(B)  Zn

(C)  Ca
(D)  Al
19. According to molecular orbital theory, which of the
following will not be a viable molecule?

(A)  H 2−
2

(B) 
He 2+
2

(C) He +2

(D) 
H −2

20. The major product formed in the following reaction is:
O

-9

(B)  5 × 10 M
-9
(D)  1.1 × 10 M

HI
Heat

O

5/18/2018 5:14:29 PM


JEE Mains 2018 Paper    xiii

I


(A) 

OH

(B) 

OH



OH

(D) 

I

I

21. Phenol on treatment with CO2 in the presence of NaOH
followed by acidification produces compound X as the
major product. X on treatment with (CH3CO)2O in the
presence of catalytic amount of H2SO4 produces:
O

(B) 
(A)  CO2H
O
CO2H
O

O

CH3

CO2H

CH3
O
O


(C) 

(D) 

O
C

O

CH3

CH3
O
OH

24. The major product of the following reaction is:
NaOMe
MeOH

(A) 5 × 10 −19

(B)  5 × 10 −8

(C) 3 × 10 −20

(D)  6 × 10 −21

28. The recommended concentration of fluoride ion
in drinking water is up to 1 ppm as fluoride ion is
required to make teeth enamel harder by converting
[3Ca3 (PO4 )2 .Ca(OH)2 ] to:

(A)  3{Ca(OH) 2 } . CaF2 
(B) [ CaF2 ]
(C) [3(CaF2 ). Ca(OH) 2 ]
(D) [3Ca 3 (PO 4 ) 2 . CaF2 ]
29. Which of the following salts is the most basic in aqueous solution?
(A) Pb(CH3COO) 2

(B)  Al(CN)3

(C) CH3COOK

(D)  FeCl3

30. Total number of lone pair of electron in I3− ion is:
OMe

A01_KUMAR_0283_01_SE_PREL.indd 13

26. An aqueous solution contains 0.10 M H2S and 0.20 M
HCl. If the equilibrium constant for the formation of
HS- from H2S is1.0 × 10 −7 and that of S2− from HSions is1.2 × 10 −13 then the concentration of S2− ions in
aqueous solution is:


(A)  +3, 0 and +4

(B)  +3, +4 and +6

(C)  +3, +2 and +4

(D)  +3, 0 and +6

23. Which type of ‘defect’ has the presence of cations in
the interstitial sites?

(A)  Metal deficiency defect (B)  Schottky defect

(C)  Vacancy defect
(D)  Frenkel defect




(A)  (NH4)2SO4

(B)  Ba(N3)2
(C)  (NH4)2Cr2O7

(D)  NH4NO2

27. The oxidation states of Cr in [ Cr(H 2 O)6 ] Cl3 , [ Cr(C6 H6 ) 2 ]
and K 2 [ Cr(CN) 2 (O) 2 (O 2 )(NH3 ) ] re­­
spectively are:

22. Which of the following compounds contain(s) no
covalent bond(s)?
KCl, PH3, O2, B3H6, H2SO4
(A)  KCl, B3H6 (B)  KCl, B2H6, PH3

(C)  KCl, H2SO4 (D)  KCl


Br

25. The compound that does not produce nitrogen gas by
the thermal decomposition is:

[Cr(H 2 O)6 ] Cl3 , [Cr(C6 H6 )2 ]

CO2H


(A) 

(D) 

OH
I


(C) 


(C) 



(B) 

OMe


(A)  12 (B)  3

(C)  6 (D)  9

5/18/2018 5:14:33 PM


xiv    JEE Mains 2018 Paper

Answer keys
1. (A)
11. (D)
21. (B)

2. (D)
12. (D)
22. (D)

3. (C)
13. (B)
23. (D)

4. (B) 5.  (D)
14. (A) 15.  (A)
24. (C) 25.  (A)

6. (A)
16. (D)
26. (C)

7. (D)
8. (B)
17. (A) or (C)18. (D)
27. (D)
28. (D)

9. (D)
19. 
(A)
29. (C)

10. 
(C)
20. (A)

30. (D)

Hints and Solutions
1. As DTf ∝ mi. Here m is same so decide by using i.

The complex giving least number of ions will have lowest
depression in freezing point and therefore highest freezing
point. Hence, option (A) is correct. (Van’t Hoff factor = 1)

Hence, the correct option is (A).
2. In acidic medium, H 2O 2 acts as an oxidant as follows

5. As methyl orange is weak organic base. So it is used in the
titration of weak base (NH4OH) vs strong acid (HCl)
MeOH

Unionized form
(Yellow)

−4

−1
 +3

+ H2 O2 →  Fe(CN)6 



−3

+ OH −


In basic medium, equilibrium lies in backward direction and
therefore it shows yellow colour.

In acidic medium, equilibrium shifts in forward direction
and therefore, colour changes from yellow to red.

Oxidation number decreases

 +2

 Fe(CN)6 



Me +

Ionized form
(Red)


Hence, the correct option is (D).

−2

+ H2 O

N

6.

Oxidation number increases

+

NH3


In alkaline medium, H 2O 2 acts as reducing agent as follows
Oxidation number increases

+2
 +3

 Fe(CN)6 



−3
−4

−1
+3
 +2

+ H2 O2 →  Fe(CN)6 



−−4
3

H

N


In it, the N-atoms present in the ring will have same pKa values (6.0), while N atom outside the ring will have different
pKa value (pKa > 7.4).

0 −2
+O
H22 O

Oxidation number decreases


Hence, two N-atoms inside the ring will remain in unprotonated from in human blood as their pKa(6.0) < pH of blood
(7.4), while the N-atom outside the ring will remain in protonated from because its pKa > pH of blood (7.4).


Hence, the correct option is (D).
3. Kjeldahl’s method cannot be not used in the case of nitro,
azo compounds and also to the compounds containing
nitrogen in the ring, e.g., Pyridine. Hence, here only
C6 H5 −NH 2 is suitable for the test.

Hence, the correct option is (A).


Hence, the correct option is (C).
4. Glucose on heating with HI gives n-hexane as followed
CHO
(CHOH)4
CH2OH

CH3
(CH2)4

HI
Δ

CH3

n-hexane
Glucose

Hence, the correct option is (B).

7. Order of basicity in increasing order is as follows
NH2
NH

(II)

A01_KUMAR_0283_01_SE_PREL.indd 14

<

NH2

(I)

<

NHCH3

(IV)

<

(III)

NH

5/18/2018 5:14:34 PM


JEE Mains 2018 Paper    xv

As Q = It

So, 12 × 96500 C = 100 × t(s)

On solving, we get
12 × 96500

hours
t=
100 × 3600

t = 3.2 hours

Hence, the correct option is (D).


Here (III)  is most basic because its conjugate acid is stabilized by equivalent resonance.

Out of (I) and (IV), (IV) is more basic due to + I effect of
-CH3 group (II) is less basic than (I) and (IV) because N
atom is sp2(more s%) hybridized.

Hence, the correct option is (D).
8.ΔG° = -RT ln K

ΔH° -TΔS° = -RT ln K
∆H° ∆S°
ln K

−
+
RT
R

10.
Br

Br

1
graph will be a straight line with slope equal

Here ln K vs
T
∆H°
. As reaction is exothermic, so ∆H° itself will be
to −
R
negative resulting in positive slope.

Br

H3N

Br
Br −

Co

Br
Br

Co

Br

H3N

Co

+

⋅

H3N


Hence, the correct option is (B).

NH3

H3N

NH3
cis-isomer

NH3
NH3
fac-isomer

Br

9. B2 H6 + 3O 2 
→ B2O3 + 3H 2O

Here 27.66 g B2 H6 , i.e., 1 mole B2 H6 requires 3 mole of
O2. Here this oxygen is produced by electrolysis of water as
follows.

F

2H 2O 4
→ 2H 2 + O 2


As 1 mole O2 is produced by 4 F charge

So 3 mole O2 will be produced by 12 F charge

H3N
Br −

Co
H3N

Br

NH3

mer-isomer

Br
NH3

H3N


As according to the balanced equation:

H3N

Br
Co

NH3
Br
trans-isomer

NH3
Br
mer-isomer (only)

H3N


Hence, the correct option is (C).

11. The sequence of the reaction is as follows
−

OH

O
NaOH
−H2O

O
Cl

C

O
O

CH3

Nucleophilic acyl substitution

Cl

OMe

OPh

O
O

C

−Cl−

OMe

C

O
Br2
EAS

Ph

O

C

OMe

o, p-directing group

Br
(Major product)
(B)

(A)


Hence, the correct option is (D).
12. Ba +2 + Na 2SO 4 
→ BaSO4 + 2 Na +
450 mL

50 mL,1M


For BaSO4 Ksp is given as

K sp (BaSO4 ) = [Ba +2 ][SO −42 ]

[SO −42 ] in 500 mL solution will be

50 × 1 = M × 500

M = 0.1


10 −10 = [Ba +2 ] × 0.1


Now, calculate [Ba+2] in original solution (450 mL) as
follows


[Ba +2 ] = 10 −9 M (in 500 mL solution)


10-9 × 500 = 450 × M

A01_KUMAR_0283_01_SE_PREL.indd 15

5/18/2018 5:14:37 PM


xvi    JEE Mains 2018 Paper

Option (B), x = 3, y = 6

10 −9 × 500 10
= × 10 −9 = 1.11 × 10 −9 M

450
9

Hence, the correct option is (D).


M=

6

z =  3 +  = 4.5
4


Hence, the correct option is (A)  (C2H4O3).
16. Na/liq. NH3 reduces alkynes into trans alkene (trans or anti
addition).

13. CH3CHO 
→ CO + CH 4
Pi = 363 Torr


As we know that,
r ∝ PRn

(1)


Here PR = reactant pressure

n = order of reaction

Now rate of reaction is 1.00 torr s-1, when reactant pressure
5 

torr = 344.85 torr.
is  363 − 363 ×
100 


Similarly rate of reaction is 0.5 torr s-1, when reactant pres33 

sure is  363 − 363 ×
 torr = 243.21 torr.
100



So, applying equation (1)
1  344.85 
=
0.5  243.21 

n


2 = (1.418)n
1

⇒ 2n

= 1.418

∴n≈2

Hence, the correct option is (B).

15
O2 (g) 
→ 6CO2 (g) + 3H2O (l)
2
15
3

Δng = 6 −
= −
2
2

ΔH = ΔU + ΔngRT

14. C6H6 (l) +

3



ΔH =  −3263900 − × 8.314 × 298  J
2



= -3267616 J
= -3267.616 kJ

Hence, the correct option is (A).

R

C

H

C=C

R

H
R
trans alkene


Hence, the correct option is (D).
17. Here BCl3 and AlCl3 are Lewis acids as both ‘B’ and ‘Al’ has
vacant p-orbitals and are e- deficient. SiCl4 is also a Lewis
acid as silicon atom has vacant 3d-orbital, so it can accept e-.

Hence, the correct option is (A) or (C).
18. Here metal is Al and the reactions are as follows

2Al + 6 H 2O 
→ 2Al ( OH )3 ↓ + 3H 2
(x)


Al(OH)3 + NaOH 
→ Na [( Al(OH) 4 )]
(Soluble)


Hence, the correct option is (D).
19. Species

Bond order
1

(A) 
B.O. = [ 2 − 2] = 0 (does not exists)
2
1
2+

(B)  He 2
B.O. = [ 2 − 0 ] = 1 (exists)
2
1
+

(C)  He 2
B.O. = [ 2 − 1] = 0.5 (exists)

2
1
−

(D)  H 2
B.O. = [ 2 − 1] = 0.5 (exists)
2

As H −2 has bond order as zero, so it cannot exist.
H 2−
2


Hence, the correct option is (A).
20. It follows SN1 reaction as follows.
CH3

15. As ratio of mass percent of C and H in CxHyOz is 6 : 1.

CH3
CH3

O


So, ratio of mole percent of C and H in CxHyOz will be 1 : 2.

Hence, x : y = 1 : 2, which is possible in options (A), (B) and (C).

C

R
Na/liq. NH3

O

CH3

⊕

O

HI
Δ


Now oxygen needed to burn CxHy

⊕

CH3

H
CH3

O

I−

H

y
y

+  x +  O2 
→ xCO2 + H2O
4
2



Now z is half of oxygen atoms needed to burn CxHy here.
y
2x +
y

2

∴ z=
=x+ 
2
4


CH3


Putting on the values of x and y from the given options:

OH

CxHy


CH3
I


Option (A), x = 2, y = 4
4

z = 2 +  = 3
4


A01_KUMAR_0283_01_SE_PREL.indd 16


Hence, the correct option is (A).

⊕

I−

OH
+
H3C
OH
+
C2H5l

5/18/2018 5:14:43 PM


JEE Mains 2018 Paper    xvii
21. Here Asprin is formed as follows
O
OH

O
C

(i) NaOH

⎛
⎜
OH ⎜
⎝H C
3

(ii) CO2, 4−7 atm, 125°C

O

O

⎛
⎜
⎜
⎝

OH

O/H+ (catalyst)

CH3
C

C 2

OH

O

(acetylation)

(iii) H+ (Kolbe’s reaction)

C

Acetyl salicylic acid (Asprin)
(Analgesic)

(X)

Hence, the correct option is (B).
22. KCl contains only ionic bond between K + and Cl − ions
( K + Cl − ) while rest compounds have covalent bonds as
follows:
H

H
B

O

H

H

H

H

HO

O

OH

H

H

O

O


Hence, the correct option is (D).
23. As in Frenkel defect, smaller ion (cations) displaces from its

actual lattice site into the interstitial sites.


[Cr(H 2O)6 ] Cl3

+3
0


K 2 [Cr(CN) 2 (O) 2 (O 2 )( NH3 )]

+6

so, X = +6

Hence, the correct option is (D).
28. [3Ca 3 (PO 4 ) 2 . Ca(OH)2 ] + 2F−

→ [3Ca 3 (PO 4 ) 2 . CaF2 ] + 2OH −


Hence, the correct option is (D).


Hence, the correct option is (D).
29. CH3COOK is most basic among the given salts as it gives
strong base KOH and weak acid CH3COOH.

24. It follows E2 mechanism as follows
Br

Oxidation states of Cr

2 + [ X + ( −2) + ( −2) + ( − 4)] = 0

P
H

Compound


[Cr(C6 H6 )2 ]

S

B

27. The oxidation states of Cr are 3, 0, 6, respectively.

NaOMe
MeOH

+ NaBr + MeOH

H


Hence, the correct option is (C).
25. Here (NH4)2SO4 an heating gives Ammonia while rest give N2.
(NH 4 ) 2SO 4 ∆

→ 2NH3 (g) + H 2SO 4


Hence, the correct option is (C).
30. I3− has 3 lone pair e- as follows
−

I

I

I


Hence, the correct option is (D).

Ba(N 3 ) 2 (s) ∆
→ Ba + 3N 2 (g)
(NH 4 ) 2Cr2O7 (s) 
→ N 2 (g) + Cr2O3 (s) + 4H 2O
NH 4 NO 2 ∆
→ N 2 (g) + 2H 2O

Hence, the correct option is (A).
2−
2H + + S
( 2 x +0.20) x

26. H 2S (aq.)
( 0.1− x )

= 0.2

= 0.1

K a = K a1 × K a2 = 1.2 × 10 −20
1.2 × 10 −20 =

(0.2) 2 × S2 − 
0.1

On solving
S2 −  = 3 × 10 −20

Hence, the correct option is (C).

A01_KUMAR_0283_01_SE_PREL.indd 17

5/18/2018 5:14:46 PM


JEE Mains 2017 Papers
1. Which of the following compounds will give significant amount of meta product during mono-nitration
reaction?
OCOCH3

OH

(A) 

(B) 
NH2

(C) 

NHCOCH3


Oxygen (61.4%); carbon (22.9%); hydrogen (10.0%);
and nitrogen (2.6%). The weight which a 75 kg person
would gain if all 1H atoms are replaced by 2H atoms is:
(A)  15 kg
(B)  37.5kg
(C)  7.5 kg
(D)  10 kg
8. Which of the following, upon treatment with tertBuONa followed by addition of bromine water, fails to
decolourize the colour of bromine?
C6H5

O

(D) 


(A) 

(B) 
Br

Br

2. ∆U is equal to:
(A)  Isochoric work
(C)  Adiabatic work

(B)  Isobaric work
(D)  Isothermal work

3. The increasing order of the reactivity of the following
halides, for the SN1 reaction is:
(I)  CH3CHCH2CH3
Cl

(II) 

CH3CH2CH2Cl

(III)   p—H3CO—C6H4—CH2Cl
(A)  (III) < (II) < (I)
(C)  (I) < (III) < (II)

(B)  (II) < (I) < (III)
(D)  (II) < (III) < (I)

4. The radius of the second Bohr orbit for hydrogen atom
is:

(Plank’s constant, h = 6.6262 × 10-34 Js; mass of
electron = 9.1091 × 10-31 kg; charge of electron,
e = 1.60210 × 10-19 C; permittivity of vaccum, ∈0 =

8.854185 × 10-12 kg-1 m-3 A2)
(A) 1.65Å
(C) 0.529Å

(B) 4.76Å
(D) 212Å

5. pKa of a weak acid (HA) and pKb of a weak base
(BOH) are 3.2 and 3.4, respectively. The pH of their
salt (AB) solution is:
(A) 7.2
(B) 6.9
(C) 7.0
(D) 1.0
6. The formation of which of the following polymers
involves hydrolysis reaction?
(A) Nylon 6
(B) Bakelite
(C)  Nylon 6, 6
(D)  Terylene
7. The most abundant elements by mass in the body of a
healthy human adult are:

A01_KUMAR_0283_01_SE_PREL.indd 9

O

O

(C) 

(D) 
Br

Br

9. In the following reactions, ZnO is respectively acting
as a/an:
(a) ZnO + Na2O → Na2ZnO2
(b) ZnO + CO2 → ZnCO3
(A)  Base and acid
(B)  Base and base
(C)  Acid and acid
(D)  Acid and base
10. Both lithium and magnesium display several similar
properties due to the diagonal relationship; however,
the one which is incorrect is:
(A)  Both form basic carbonates
(B)  Both form soluble bicarbonates
(C)  Both form nitrides
(D) Nitrates of both Li and Mg yield NO2 and O2 on
heating
11. 3-Methyl-pent-2-ene on reaction with HBr in presence
of peroxide forms an addition product. The number of
possible stereoisomers for the product is:
(A) Six
(B) Zero

(C) 
Two

(D) 
Four
12. A metal crystallises in a face centred cubic structure.
If the edge length of its unit cell is ‘a’, the closest
approach between two atoms in metallic crystal will be:

(A) 2a
(C)  2a

(B) 
2 2a
(D)

a

2
13. Two reactions R1 and R2 have identical pre­-exponential
factors. Activation energy of R1 exceeds that of R2 by
10 kJ mol-1. If k1 and k2 are rate constants for r­ eactions

5/10/2017 11:19:39 AM


x    JEE Mains 2018 Papers
R1 and R2 respectively at 300 K, then ln(k2/k1) is equal
to (R = 8.314 J mol-1K-1):

(A) 8

HOH2C

O CH2OH

(B) 12

(C) 6

(D) 4
14. The correct sequence of reagents for the following
conversion will be:
O


(D) 

HO

CH3

OH
OH

OH

17. Given
C( grahite ) + O 2 ( g ) → CO 2 ( g ) ;

∆ r H° = − 393.5 kJ mol −1


HO

CHO

(A)   Ag ( NH3 )2 

+

CH3
CHO

OH − , H + /CH3OH, CH3 MgBr
+

(B)  CH3 MgBr, H + /CH3OH,  Ag ( NH3 )2  OH −
(C)  CH3 MgBr,  Ag ( NH3 )2 

+

OH − , H + /CH3OH

+

(D)   Ag ( NH3 )2  OH − , CH3 MgBr, H + /CH3OH
15. The Tyndall effect is observed only when following
conditions are satisfied:
(a)The diameter of the dispersed particles is much
smaller than the wavelength of the light used.
(b)The diameter of the dispersed particle is not much
smaller than the wavelength of the light used.
(c)
The refractive indices of the dispersed phase

and dispersion medium are almost similar in
magnitude.
(d)The refractive indices of the dispersed phase and
dispersion medium differ greatly in magnitude.
(A)  (a) and (d)
(B)  (b) and (d)
(C)  (a) and (c)
(D)  (b) and (c)
16. Which of the following compounds will behave as a
reducing sugar in an aqueous KOH solution?
CH2OH

(A)  HOH2C
O
HO


(B)  HOH2C

OCOCH3

1
H 2 ( g ) + O 2 ( g ) → H 2 O (1) ;

2
∆ r H° = − 285.8 kJ mol −1

C O 2 ( g ) + 2H 2 O ( l ) → CH 4 ( g ) + 2O 2 ( g ) ;

∆ r H° = + 890.3 kJ mol −1

Based on the above thermochemical ­equation,
the value of DrH° at 298 K for the reaction
C( graphite) + 2H 2 (g) → CH 4 (g) will be:
(A)  +74.8 kJ mol-1
(B)  +144.0 kJ mol-1
-1
(C) -74.8 kJ mol
(D) 
-144.0 kJ mol-1
18. Which of the following reactions is an example of a
redox reaction?
(A)  XeF4 + O 2 F2 → XeF6 + O 2
(B)  XeF2 + PF5 → [ XeF] PF6 −
+

(C)  XeF6 + H 2 O → XeOF4 + 2HF
(D)  XeF6 + 2H 2 O → XeO 2 F2 + 4HF
19. The products obtained when chlorine gas reacts with
cold and dilute aqueous NaOH are:
(A)  ClO − and ClO3−
(B)  ClO −2 and ClO3−
(C)  Cl − and ClO −
(D)  Cl − and ClO 2−
20. The major product obtained in the following reaction
is:
Br

OH

CH2OH

O

H
C6H5

HO

BuOK

C6H5


(C)  HOH2C

OH
CH2OH

O
HO
OH

A01_KUMAR_0283_01_SE_PREL.indd 10

Δ

(A)  ( ±)C6 H5 CH(O t Bu )CH 2 CH6 H5
(B)  C6 H5 CH=CHC6 H5

OCH3

(C)  ( + ) C6 H5 CH(O t Bu )CH 2 H5

(D)  ( −)C6 H5 CH(O t Bu )CH 2 C6 H5

5/10/2017 11:19:42 AM


JEE Mains 2018 Papers    xi
21. Sodium salt of an organic acid ‘X’ produces effervescence with conc. H2SO4.‘X’ reacts with the acidified
aqueous CaCl2 solution to give a white precipitate
which decolouriszes acidic solution of KMnO4.‘X’ is:
(A) C6H5COONa
(B) HCOONa
Na 2 C2 O 4
(C) CH3COONa
(D) 

(B) 

22. Which of the following species is not paramagnetic?
(A) NO
(B) CO
(C) O2(D) 
B2

(C) 

23. The freezing point of benzene decreases by 0.45°C

when 0.2 g of acetic acid is added to 20 g of benzene.
If acetic acid associates to form a dimer in benzene,
percentage association of acetic acid in benzene will
be:

(Kf for benzene = 5.12 K kg mol-1)
(A) 64.6%
(B) 80.4%
(C) 74.6%
(D) 94.6%
24. Which of the following molecules is least resonance
stabilized?
(A) 



(B) 
O

(C) 



CHO
CHO
CHO
COOH
CHO

(D) 

CHO

27. A water sample has ppm level concentration of following anions:
F− = 10; SO 24 − = 100; NO3− = 50

the anion/anions that make/makes the water sample
unsuitable for drinking is/are:
(A) Only NO3−
−
(B) Both SO 2−
4 and NO3

(C) Only F−
(D) Only SO 2−
4

(D) 

N

OH

O

25. On treatment of 100 ml of 0.1 M solution of COCl3.
6H2O with excess AgNO3; 1.2 × 1022 ions are precipitated. The complex is:
(A) [CO(H2O)4 Cl2]Cl . 2H2O
(B) [CO(H2O)3Cl3] . 3H2O
(C) [CO(H2O)6]Cl3
(D) [CO(H2O)5Cl]Cl2 . H2O

26. The major product obtained in the following reaction
is:
O
O
DIBAL – H

28. 1 gram of a carbonate (M2CO3) on treatment with
excess HCl produces 0.01186 mole of CO2. The molar
mass of M2CO3 in g mol-1 is:
(A) 1186
(B) 84.3
(C) 118.6
(D) 11.86
29. Given

E°Cl /Cl = 1.36V, E°Cr
−

2


E°Cr O
2

2−
7

/Cr 3+

3+

/Cr

= −0.74V

= 1.33V, E°MnO−4 /Mn 2+ = 1.51V.


Among the following, the strongest reducing agent is:
(A) Cr
(B) Mn2+
3+
(C) Cr (D) 
Cl30. The group having isoelectronic species is:
(A) O 2 − , F− , Na + , Mg 2+

COOH

(B) O − , F− , Na, Mg+
(C)  O 2 − , F− , Na, Mg 2+

OH

(A) 

CHO

(D)  O − , F− , Na + , Mg 2+

COOH

A01_KUMAR_0283_01_SE_PREL.indd 11

5/10/2017 11:19:43 AM


xii    JEE Mains 2018 Papers

Answer keys
1. (C)2. 
(C)3. 
(B)4. 
(D)5. 
(B)6. 
(A)7. 
(C)8. 
(A)9. 
(D)10. 
(A)
11.  (D)12. 
(D)13. 
(D)14. 
(A)15. 
(B)16. 
(A)17. (C)18. 
(A)19. 
(C)20. 
(B)
21.  (D)22. 
(B)23. 

(D)24. 
(D)25. 
(D)26. 
(B)27. 
(C)28. 
(B)29. 
(A)30. 
(A)

Hints and Solutions
1.Nitration is carried out in presence of concentrated HNO3
and concentrated H2SO4. Here, aniline acts as base, in presence of H2SO4 its protonation takes place and anilinium ion
is formed.
−

⊕

NH2

NH3HSO4

4.Radius of nth Bohr orbit in H-atom = 0.53

Radius of second Bohr orbit =

0.53 × ( 2) 2
1


= 2.12 Å

H⊕

5.pKa(HA) = 3.2

H2SO4


Anilinium ion is strongly deactivating group and meta
directing in nature so it gives meta nitration product in significant amount. (≈ 97%).
⊕

NH2

−

NH3HSO4
conc.H2SO4
+ conc.HNO3

NO2

2.Using 1st law:

∆U = q + w

For adiabatic process:

q=0

So, ∆U = w

Hence work involved in adiabatic process is at the expense
of change in internal energy of the system.
3.For SN1 reaction, reactivity is decided by ease of dissociation of alkyl halide


pKb (BOH) = 3.4

As given salt is of weak acid and weak base.
1
1

So, pH = 7+ pK a − pK b
2
2


1
1
  = 7+ (3.2) − (3.4)
2
2



  = 6.9

6.Formation of Nylon6 involves hydrolysis of its monomer
(caprolactum) in initial state as follows:

NH

O

O
Hydrolysis

Caprolactum

+

H3N—
—CH2—
—CH2—
—CH2—
—CH2—
—CH2—
—C—
— OΔ/Polymerization

O
—
—
[ HN—
—
( CH2—
—
)5 C—
]n

R⊕ + X −

R−X

n2
Å
Z

Nylon6

⊕


Higher the stability of R (carbocation) higher would be
reactivity of SN1 reaction.

As stability of cation follows order.
⊕
—CH2—
—CH2
CH3—
⊕
< CH3—
—CH—
—CH2 —
—CH3

⊕
< p—
— H3CO—

—C6H4—
—CH2


Hence, the correct order is
II < I < III

A01_KUMAR_0283_01_SE_PREL.indd 12

7.Mass in the body of a healthy human adult has:

Oxygen = 61.4%, carbon = 22.9%,

Hydrogen = 10.0% and Nitrogen = 2.6%

Total weight of person = 75 kg

Mass due to 1H is = 75 ×

10
= 7.5 kg
100


1

H atoms are replaced by 2H atoms.

Hence, mass gain by person = 7.5 kg

5/16/2017 3:51:04 PM


CH3

CH3

H

Br

H

CH3

Br

H

H 3C

H

Et

Et

JEE Mains
2018 Papers    xiii
(II)

(I)
O

8.

CH3

O
tert-BuONa

Br

O-tBu
(fails to decolorize the
colour of bromine)
(no unsaturation)
C6H5

Br

H

H

CH3


C6H5

tert-BuONa

Br


O
tert-BuONa

Br
H

Et

Et

(III)

(IV)

2a = 4 R

(it decolorizes
bromine solution due
to unsaturation)
O

O
tert-BuONa

− Ea

K = A ⋅ e RT


K1 = A ⋅ e − E a 1

RT

(1)


K 2 = A ⋅ e − Ea 2

RT

(2)


So, equation (2)/(l) ⇒

Br
(it decolorizes
bromine solution due
to unsaturation)


9.ZnO is an amphoteric oxide but in given reaction it acts as
follows:

(a) ZnO + Na2O → Na2ZnO2

 acid base
salt

(b) ZnO + CO2 → ZnCO3


base acid
salt
10. Mg can form basic carbonate like,

K2
=e
K1

→ 4 MgCO3 ⋅ Mg(OH) 2 ⋅ 5H 2O ↓


14.

O

O
[Ag(NH3)2]OH
Tollens reagent

CHO

CO2H

H+/CH3OH
(esterification)

+2HCO −3

O

Br

4

C

3

5

O

HBr
+H2O2


CH3

CH3

H

Br

H

CH3

Br

H

H 3C

H

Et

Et

(I)

(II)

CH3

OCH3
CH3MgBr

Anti markownikov product
(4 stereo isomers possible
due to 2 chiral centres as
molecule is asymmetric )

3-methyl pent-2-ene



RT

 K  (Ea1 − Ea 2 )
10, 000

Hence, ln  2  =
=
= 4.
× 300
K
RT
.
8
314
 1


While Li can form only carbonate (Li2CO3) not basic
carbonate.
11.

1

(E a1 − E a 2 )

(As Pre-exponential factors of both reactions in same)

5Mg +2 + 6C32 − + 7H 2O

2

2a
a
=
2
2


Hence, closest distance (2R) =
13. Using arrhenius equation,

Br



H
H 3C

12. In FCC unit cell atoms are in contact along face diagonal.

So,

(it decolorizes
bromine solution)

O

CH3

CH3

HO

H3C

C

CH3

OH

15. It is factual.
16. (i) Ester in presence of aqueous KOH solution give SNAE
reaction so following reaction takes place.

CH3

Br

H

H

CH

A01_KUMAR_0283_01_SE_PREL.indd 133

H

Br

H 3C

H

5/16/2017 3:51:06 PM


xiv    JEE Mains 2018 Papers
HOCH2

CH2OH

O

HOCH2

O

CH2OH

O

Aq. KOH
SNAE

O—C—Me

O

CHO

−

O

+ Me—C—O

⋅

−

OH

⋅

Hemiketal
Ring opening

O

HOCH2
⊕ ve silver
mirror
test

−

CH2OH
O

Tollen’s

2CH3COOH


Reagent

OH


(ii) In above compound, in presence of aq. KOH (SNAE)
reaction takes place and a-Hydroxy carbonyl compound
is formed which gives ⊕ve Tollen’s test. So this compound
behaves as a reducing sugar in an aqueous KOH solution.
17. C O 2 ( g ) + 2H 2O ( l ) → CH 4 ( g ) + 2O 2 ( g ) ; ∆ r H°= 890.3
∆ f H°− 393.5 − 285.8

?

0

∆ r H° = ∑ ( ∆ r H°) products − ∑ ( ∆ r H°) reactant

890.3 = 1 × ( ∆ f H° ) CH 4 + 2 × 0  − 1 × ( −393.5 ) + 2 ( −285.8 ) 



( ∆ f H° )CH
+4

4

= 890.3 − 965.1 = −74.8 kJ/mol

+1

+6

X eF6 + O02

18. X eF4 + O 2 F2 →

Here, xenon undergoes oxidation while oxygen undergoes
reduction. (Redox Process)
19. Cl2 + 2OH−

[cold
and dilute]

H
C6H5

C6H5

H

i =1−


α
Here a is degree of association
2


∆Tf = iK f m
 0.2 
 60 
 α


0.45 = 1 −  ( 5.12 ) 
20
2

1000
1−


α
= 0.527
2

α = 0.945

Percentage degree of association = 94.5%
O

is nonaromatic (non-planar) and hence least

reasonance stabilized.

(A)

Benzene is aromatic (6pe-)


(B)

furan is aromatic (6pe-)
O

C6H5

C6H5

( CH3COOH )2

1 

i = 1 +  − 1 α
2 

24. (D)

Cl + ClO− + H2O
Hypochlorite

20. Elimination reaction is highly favoured if:

(a) Bulkier base is used

(b) Higher temperature is used

Hence in given reaction biomolecular ellimination reaction
provides major product.
Br

22. Using molecular orbital theory

NO(15e-) ⇒ One unpaired electron is present in π *

molecular orbital. (Paramagnetic)

CO(14e-) ⇒ No unpaired electron is present (Diamagnetic)

O2 (16) ⇒ Two unpaired electrons are present in π *

Molecular orbitals. (Paramagnetic)

B2(10) ⇒ Two unpaired electros are present in π

bonding molecular orbitals. (Paramagnetic)
23. In benzene acetic acid dimerises as follows:

+ tBuOH + Br ⊕

pyridine is aromatic (6pe-)


(C)

H

N
−

OtBu

25. Moles of complex =

21. Na C O + H SO
2 2 4
2
4

Na2SO4 + CO↑ + CO2↑ + H2O

Na2C2O4 + CaCl2


CaC2O4↓ + 2NaCl

conc.

(white ppt.)

5CaC2O4↓ + 2KMnO4 + 8H2SO4

(purple)

(colourless)

1000

100 × 0.1
= 0.01 mole
1000


Moles of ions precipitated with excess of AgNO3

=

K2SO4 + 5CaSO4 − 2MnSO4 + 10CO2 + 8H2O

A01_KUMAR_0283_01_SE_PREL.indd 14


=

Molarity × volume ( ml )

1.2 × 10 22

6.02 × 10 23


= 0.02 moles

5/16/2017 3:51:08 PM


JEE Mains 2018 Papers    xv

Number of Cl − present in ionization sphere =
Mole of ion precipitated with exess AgNO3 0.02
=2
=

0.01
Mole of complex

It means 2Cl − ions present in ionization sphere.

Hence, complex is [CO(H2O)5Cl]Cl2 . H2O
26. DIBAL–H is electrophilic reducing agent which reduces
cynide, esters, lactone, amide, carboxylic acid into corresponding aldehyde (partial reduction).
27. NO3− : The maximum limit of nitrate in drinking water can
be 50 ppm. Excess nitrate in drinking water can cause diseases like methemoglobinemia, etc.
: above 500 ppm of SO 2−

SO 2−
4 ion in drinking water causes
4

laxative effect otherwise at moderate levels it is normally
harmless.

F− : Above 2 ppm concentration of F− in drinking water
causes brown mottling of teeth.

Hence, the concentration given in question of SO 2−
and
4
NO3− in water is suitable for drinking but the concentration

F−

(i.e., 10 ppm) makes water unsuitable for drinking
of
purpose.

A01_KUMAR_0283_01_SE_PREL.indd 15

28. Given chemical equation

M 2CO3 + 2HCl → 2MCl + H 2O + CO 2

1 gm
0.01186 mol

from
the
balanced
chemical

equation.
⇒
1 = 0.01186
M

⇒ M = 84.3 gm/mol
29. E°MnO4− /Mn +2 = 1.51V (1)
⋅

E°Cl 2 /Cl − = 1.36V (2)

⋅

E°Cr2 O7−2 /Cr +3 = 1.33V (3)

⋅

E°Cr +3 /Cr = −0.74 (4)

⋅


As Cr+3 is having least reducing potential, so Cr is the best
reducing agent here.
30.

ionsO-2F-
Na+
Mg+2

Atomic number =8
9
11
12
10101010

Number of e − =

O 2 − , F− , Na + , Mg+2 are isoelectronic species here.


5/10/2017 11:19:49 AM