Concise inorganic chemistry for JEE (main advanced)

A number of well known books name the main groups and the transition elements as A and B subgroups, which dates back to the older Mendeleev periodic table of more than half a century ago

ISBN 978-81-265-9831-1

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 Chapter opener with an opening vignette related to

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 Reorganization of chapters as per JEE syllabus flow

–Chemical Bonding combined to cover ionic, covalent

and metallic bonding together Chapters on s-, p-, d-

and f- block elements combined to form single chapter

each, covering just the required topics

 Additional chapters on Hydrolysis, Metallurgy and

Qualitative Salt Analysis for complete coverage of JEE

syllabus

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Atomic Nucleus and Spectra

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About the Book

The book is an adaptation of the classic book Concise Inorganic Chemistry by J.D LEE (fifth edition), which is widely used by students preparing for JEE This adapted version provides a more concise and relevant treatment of Inorganic Chemistry as per JEE syllabus requirements The concepts are explained in a simple and straightforward manner Yet the book provides a through grounding

of the subject, helping students approach the examination with confidence

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J.D Lee Concise Inorganic Chemistry for JEE (Main & Advanced)

Sudarsan Guha

J.D Lee Concise Inorganic Chemistry for JEE (Main & Advanced)

Adapted by

J.D Lee Concise Inorganic Chemistry

for JEE (Main & Advanced)

Copyright © 2019 by Wiley India Pvt Ltd., 4436/7, Ansari Road, Daryaganj, New Delhi-110002

All rights reserved No part of this book may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or scanning without the written permission of the publisher This book is an adaptation of Concise Inorganic Chemistry 5/e by J.D Lee (ISBN: 978-81-265-1554-7) All rights remain with respective holders

Limits of Liability: While the publisher and the author have used their best efforts in preparing this book, Wiley and the

author make no representation or warranties with respect to the accuracy or completeness of the contents of this book, and specifically disclaim any implied warranties of merchantability or fitness for any particular purpose There are no warranties which extend beyond the descriptions contained in this paragraph No warranty may be created or extended by sales representatives or written sales materials The accuracy and completeness of the information provided herein and the opinions stated herein are not guaranteed or warranted to produce any particular results, and the advice and strategies contained herein may not be suitable for every individual Neither Wiley India nor the author shall be liable for any loss of profit or any other commercial damages, including but not limited to special, incidental, consequential, or other damages

Disclaimer: The contents of this book have been checked for accuracy Since deviations cannot be precluded entirely, Wiley

or its author cannot guarantee full agreement As the book is intended for educational purpose, Wiley or its author shall not

be responsible for any errors, omissions or damages arising out of the use of the information contained in the book This publication is designed to provide accurate and authoritative information with regard to the subject matter covered It is sold

on the understanding that the Publisher is not engaged in rendering professional services

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Fourth Edition: 2017

Reprint: 2019

ISBN: 978-81-265-9831-1

www.wileyindia.com

Concise Inorganic Chemistry by J.D Lee is a book widely used by students reparing for JEE as the most comprehensive and authentic text for understanding Inorganic Chemistry The purpose of adaptation of this book is to provide a complete textbook of Inorganic Chemistry that covers the entire syllabus of JEE (Main and Advanced)in proper sequence

of topics and provides in-depth explanation of topics The use of book should give confidence

to the students to apply their knowledge to problem-solving and attempting JEE

In this new (fourth) edition, major changes have been made in the Chapter 8: Hydrogen, where the concept of hydrogen bonding is now explained with specific examples relevant

to JEE Chapter 9: The s-Block Elements has been made more concise with more focus on

topics required from JEE perspective Major changes have been made in Chapter 10: The

p-Block Elements It is now divided into six separate parts as Group 13, Group 14, Group

15, Group 16, Group 17 and Group 18 Elements Each part is followed by a separate set

of exercises for that particular group Miscellaneous questions based on multiple concepts have been placed at the end of the chapter Apart from this new questions have been included in the exercises at the end of most of the chapters

I would like to acknowledge my students for their intellectual doubts and my colleagues for their valuable arguments in various aspects of the subject This enhanced

my understanding of the subject and helped me to teach better I am especially indebted to

my college Belur Ram Krishna Mission, Calcutta University for teaching me ‘How to read and learn chemistry?’ and Bansal classes where I have got the opportunity to apply my knowledge and teach chemistry I am thankful to my promise to make this book as ‘only one book for Inorganic Chemistry’ engineering aspirants

For the future also, any suggestions for the improvement of this book are welcome by the author

Sudarsan Guha

M Tech (IIT-Kanpur)

Note to the Student

The Joint Entrance Examination (JEE) comprises the Main and Advanced examinations,

which are essential stepping stones for all engineering aspirants The JEE Main is focused

primarily on evaluating the conceptual strength of the students The JEE Advanced would

further judge the ability of top performers in JEE Main to extend the conceptual strength

to application-based problem solving For complete preparation of these prestigious

examinations, a book that is rich in conceptual strength and enriched with problem-solving

tools and assessment would serve as a one-stop solution!

Concise Inorganic Chemistry by J.D Lee has been the definitive text for learning

Inorganic Chemistry since its first edition appeared about 45 years ago The book captures

the fundamentals of the subject in a simple and logical framework of factual knowledge

The description is long enough to cover the essentials, yet short enough to be interesting Its

unparalleled approach to teaching Inorganic Chemistry is the reason why it is probably the

most favoured resource for an IIT aspirant like you today

In collaboration with experts in JEE (Main & Advanced) coaching, the fifth edition of

the original book has now been adapted to give you the best book available in Inorganic

Chemistry for preparing for the toughest engineering entrance exam in India This adaptation

offers the dual advantage of unmatched explanation of concepts as developed by “Master

teacher” and appropriate applications of the concepts to problem solving as developed by

an expert in this area

Let’s walk through some of the special book features that will help you in your efforts

to take the JEE (Main & Advanced) with confidence

The original book has been reorganized in a manner to provide more structured approach as per the JEE (Main & Advanced) syllabus requirement The progression is from basic concepts such as Structure of

an Atom, Periodic Table and Periodic Properties and Chemical Bonding

to practical aspects of Metallurgy and Qualitative Salt Analysis This is followed by description on Hydrogen

and its compounds and some

compounds and properties of s-, p- , d-

and f-block elements

A STRUCTURE OF THE BOOK

7 Qualitative Salt Analysis

8 Hydrogen and its Hydrides

9 The s-Block Elements and their compounds

10 The p-Block Elements and their Compounds

11 The d-Block Elements and their Compounds

12 The f-Block Elements and their Compounds

Each chapter starts with an opening vignette related to the topic, and listing of contents of that chapter This gives you an overview of the chapter and helps to identify the extent of

coverage

CHAPTER OPENER

Concepts are explained in a

man-ner easy to read and understand

They are descriptive to the extent

required and provide reasons for

the structure, properties and

reac-tions of compounds Many

fasci-nating applications of inorganic

compounds are also explained

CONCEPT EXPLANATION

B PEDAGOGY

The text is sprinkled with multiple figures which pre-sent two-dimensional rep-resentation of compounds and their structures This visual representation en-hances understanding and helps the student visualize what a molecule may look

like

A large number of tables

capture data on structure,

properties and other such

parameters The tabular

repre-sentation supports

compara-tive study of properties and

draws out changing trends in

them The trends of various

properties of elements along

the periodic table are also

amply illustrated

TABLES

Application of concepts to problem solving is the core of JEE (Main & Advanced),

so it is important to test our understanding of concepts For the test to be effective,

the assessment technique should be comprehensive and in the context of this

book, also in resonance with the JEE Main and JEE Advanced paper pattern

Each part of the assessment should be modeled on the actual paper pattern

because unless the student practices the JEE way, he/she will not be sufficiently

equipped to take the examination Keeping this in mind, the assessment has been

divided into:

C ASSESSMENT – AS PER JEE (MAIN & ADVANCED) PATTERN

These are the regular

mul-tiple choice questions with

four choices provided Only

one among the four choices

will be the correct answer

SINGLE CORRECT CHOICE TYPE QUESTIONS

These are multiple choice questions with four choices provided One or more of the four choices provided

choice questions based

on it The questions are

of single correct answer

type (with some

excep-tions)

COMPREHENSION TYPE QUESTIONS

These questions check the analytical and reasoning skills of the students Two statements are provided – Statement I and Statement

II The student is expected to verify if (A) both statements are true and if both are true, verify if statement I follows from statement II; (B) both statements are true and if both are true, verify if state-ment II is not the correct reasoning for statement I; (C), (D) which of the state-

ments is untrue

The questions in this tion are numerical prob-lems for which no choices are provided The students are required to find the exact answers to numeri-cal problems which can

sec-be one-digit or two-digit numerals

INTEGER ANSWER TYPE QUESTIONS

These questions are the regular “Match the Follow-ing” variety Two columns each containing 4 subdivi-sions or first column with four subdivisions and second column with more subdivisions are given and the student should match elements of column I to that of column II There can

be one or more matches

MATRIX–MATCH TYPE QUESTIONS

SI units for energy are used throughout this edition, thus making a comparison of

thermo-dynamic properties easier Ionization energies are quoted in kJ mol–1, rather than ionization

potentials in eV Older data from other sources use eV and may be converted into SI units

(1 kcal = 4.184 kJ, and 1 eV = 23.06 × 4.184 kJ mol–1)

Meters are strictly the SI units for distance, and bond lengths are sometimes quoted in

nanometers (1 mm = 10–9 m) However Ångström units Å (10–10 m) are a permitted unit of

length, and are widely used by crystallographers because they give a convenient range of

numbers for bond lengths Most bonds are between 1 and 2 Å (0.1 to 0.2 nm) Ångström

units are used throughout for bond lengths

The positions of absorption peaks in spectra are quoted in wave numbers cm–1, because

instruments are calibrated in these units It must be remembered that these are not SI units,

and should be multiplied by 100 to give SI units of m–1, or multiplied by 11.96 to give J mol–1

The SI units of density are kg m–3, making the density of water 1000 kg m–3 This

conven-tion is not widely accepted, so the older units of g cm–3 are retained so water has a density

of 1 g cm–3

In the section on magnetism both SI units and Debye units are given, and the relation

between the two is explained For inorganic chemists who simply want to find the number

of unpaired electron spins in a transition metal ion, Debye units are much more convenient

For a long time chemists have arranged the elements in groups within the periodic table in

order to relate the electronic structures of the elements to their properties, and to simplify

learning There have been several methods of naming the groups

A number of well known books name the main groups and the transition elements as A

and B subgroups, which dates back to the older Mendeleev periodic table of more than half

a century ago Its disadvantages are that it may over emphasize slight similarities between

the A and B subgroups, and there are a large number of elements in Group VIII

In earlier versions of this book the s-block and the p-block were numbered as Groups

I to VII and 0, depending on the number of electrons in the outer shell of the atoms, and

the transition elements were dealt with as triads of elements and named as the top element

in each group of three

The IUPAC has recommended that the main groups and the transition metals should

be numbered from 1 to 18 This system has gained acceptance, and has now been adopted

throughout this book

Appendix G Appendix H Appendix I Appendix J Appendix N(K) Appendix O(L)

D USE OF SI UNITS

E NOMENCLATURE FOLLOWED IN THE PERIODIC TABLE

Appendix A Abundance of the elements in the Earth’s crust

Appendix B Melting points of the elements

Appendix C Boiling points of the elements

Appendix D Densities of solid and liquid elements

Appendix E Electronic structures of the elements

Appendix F Some average single bond energies and some double

and triple bond energies

Appendix G Solubilities of main group compounds in water

Appendix H Atomic weights based on 12 C= 12.000

Appendix I Values of some fundamental physical constants

Appendix J Electrical resistivity of the elements at the stated temperature

Appendix K Hardness of minerals — Mohs’ scale

Preface v

Prediction of period and group number of an element from its electronic confguration 34

Contents

3.12 Examples of Molecular Orbital Treatment for Homonuclear Diatomic Molecules 92

Some special cases 102

3.15 The Ionic Bond 104

Answers 154

xviii

5.11 Tetragonal Distortion of Octahedral Complexes (Jahn-Teller Distortion) 189

5.15 Extension of the Crystal Field Theory to Allow for Some Covalency 196

6 Metallurgy 217

6.2 Principal Steps in the Recovery of a Metal from its Ore 219

xx

Detection of carbonate and bicarbonate when both are present together 267

Some other tests for SO 2

7.9 Tests for Sulphate (SO2

7.13 Tests for Permanganate (MnO

-4) and Manganate (MnO2

Answers 319

8 Hydrogen and the Hydrides 321

Answers 343

9 The s-Block Elements and their Compounds 345

xxii

9.8 Oxosalts – Carbonates, Bicarbonates, Nitrates, Nitrites and Sulphates 354

9.16 Differences between Lithium and the Other Group 1 Elements 361

9.36 Differences between Beryllium and the Other Group 2 Elements 379

Matrix–Match Type Questions 384Answers 384

10 The p-Block Elements and their Compounds 387

Size of atoms and ions 390

10.17 Differences Between Carbon, Silicon and the Remaining Elements 415

Arsine AsH 3 , stibine SbH 3 and bismuthine BiH 3 453

Dichlorine heptoxide Cl 2 O 7 531

Answers 553

11 The d-Block Elements and some of their Compounds 561

Appendices 593–612 Appendix A Abundance of the Elements in the Earth’s Crust 593

Appendix D Densities of the Solid and Liquid Elements 597

Appendix E Electronic Structures of the Elements 598

Appendix F Some Average Single Bond Energies and Some Double and

Appendix G Solubilities of Main Group Compounds in Water 603

Appendix H Atomic Weights Based on 12 C= 12.000 605

Appendix I Values of Some Fundamental Physical Constants 607

Appendix J Electrical Resistivity of the Elements at the Stated Temperature 608

P1 P1 JEE (Main) Papers

JEE (Advanced) Paper

Sequence of filling of energy levels.

1.1 | ATOMS

An atom is the smallest entity of an element which retains all of its properties It consists of several stable and unstable fundamental particles The examples of stable particles are neutron, proton and electron and those of unstable particles are meson, positron, neutrino, antineutrino and antiproton

The fundamental stable particles are of interest to us here

The characteristics of the stable fundamental particles that make up the atom are listed in Table 1.1

All atoms consist of a central nucleus surrounded by one

or more electrons in orbitals The nucleus always contains tons and all nuclei heavier than hydrogen contain neutrons too (Figure 1.1)

pro-The protons and neutrons together make up most of the mass of an atom Both protons and neutrons are particles of unit mass, but a proton has one positive charge and a neutron

is electrically neutral (i.e carries no charge)

An atom is represented as ZXA , where A is the mass number (i.e n + p) and Z is the atomic number (i.e p or e).

1

Extra nuclear part (place of electrons) Nucleus

(place for neutron and proton)

Figure 1.1 Structure of an atom

6f 6g 5g 6p

7p 8p 7s 8s 6s

4p 5p

4f 5d 6d

4d 3d 2p 3p

1.2 | SOME IMPORTANT DEFINITIONS

Some important defnitions related to atomic structure of atoms are described as follows:

1 Isotopes: Elements having the same atomic number but different mass number are known as isotopes

For example,

a 1 1

1 2 1 3

Ar and Ca

b 6 14

7 14

C and N

3 Isotones: Elements having the same number of neutrons are known as isotones For example,

a 12 24

11 23

C and O

d 15 31

16 32

P and S

4 Isodiaphers: Elements having the same value of isotopic excess are known as isodiaphers, where

isoto-pic excess = (A – 2Z) For example,

a 15 31

b C , O , T , Cr14 18 3 50, all have isotopic excess of (A − 2Z) = 2

Table 1.1 Characteristics of fundamental particles of an atomName of

particle Discovery Mass Nature of charge Amount of charge Radius Presence in the atom

Electron (e)

(−1e0 )         

J.J Thomson,

1897 0.000548 amuor

9.12 × 10 –28 g or

9.12 × 10 –31 kg (1/1837 th of

H atom)

Negatively charged − 1.602 × 10 –19 C

or

− 4.8 × 10 –10 esu  

— Outside the

nucleus of an atom

Proton (p)

(1H 1 ) E Rutherford, 1911 1.0076 amuor Positively charged + 1.602 × 10 –19 C 1.2 × 10 –12 cm Inside the nucleus

of an atom 1.6725 × 10 –24 g

Cr and Fe , both have isotopic excess of (A − 2Z) = 4.

5 Isoelectronic species: The species having the same number of electrons are known as isoelectronic

spe-cies (It may be an atom, ion or a molecule.) For example,

Now-a-days the defnition of isoelectronic species is also observed to extend to include the species having the same number of valence shell electrons (described later in the section on Classifcation of

elements as s, p, d and f-block elements) For example, the following species can also be considered

isoelectronic because they have the same number of valence shell electrons:

4 2 4 2

6 Isosters: Species that are isoelectronic as well as consist of the same number of atoms are known as

isosters For example,

1.3 | ELECTRONIC CONFIGURATION OF AN ATOM

To defne the position of an electron in an atom, the following terms need to be defned:

1 Orbital: It is defned as the space occupied by the electrons around the nucleus of an atom where the

probability of fnding an electron is the maximum

2 Quantum numbers: These are the parameters required to characterize an orbital or an electron There

are four different quantum numbers which are named as follows:

a Principal quantum number (denoted by n)

b Azimuthal quantum number (denoted by l)

c Magnetic quantum number (denoted by m or m l)

d Spin quantum number (denoted by s or m s)

An orbital can be described by the frst three quantum numbers, that is, n, l and m, while the description of

an electron requires all four quantum numbers, that is, n, l, m and s.

Quantum numbers

The characteristic features of the four quantum numbers are described as follows:

1 Principal quantum number (n): This quantum number indicates the distance of an electron from the

nucleus It can have values of 1, 2, 3, 4 … up to ∞ As the value of n increases, the distance of the electron/

orbital from the nucleus increases as well as the energy of the electron increases

Principal quantum numbers having different values of n are also considered as different energy

shells which are represented as follows:

Energy shells K L M N O P Q

2 Azimuthal quantum number (l): This quantum number indicates the shape of an orbital (not of

elec-tron) and can have values from 0 to (n–1) for a particular value of n For example, for n = 5, the value

of l are 0, 1, 2, 3, 4.

Each value of l indicates the sub-energy level or subshell within the particular shell or energy level,

which are denoted as follows:

Subshell or sub-energy level s p d f g

Note: The notations for the sub-energy levels come from the spectroscopic terms that were used to

describe the atomic spectra and have the following full form:

s →sharp f → fundamental

p →principal g → generalized

d → diffusedThese subshells have different shapes which are depicted in Table 1.2

Table 1.2 The shapes of subshells

or

(Continued)

1.3 Electronic Configuration of an Atom

Note:

(i) f and g subshells are of complicated shape and beyond the scope of syllabus.

(ii) These shapes of subshells are not experimentally observed as these are the 3D – plots of solution

of Schrödinger wave equation which is not part of the syllabus for JEE

3 Magnetic quantum number (m or m l): This quantum number indicates the possible orientations of

an orbital in space The value of m for a particular value of l varies from +l to –l including zero For

The different values of m for a particular value of l gives the possible orientations of the corresponding

orbital in space Each possible orientation is considered as a particular orbital

a s-subshell consists of one orbital that is known as s-orbital.

b p-subshell consists of three orbitals that are known as p x , p y and p z orbitals which are lying along the respective axis (Figure 1.2)

z

p x y

x

z

p y y

x

p z

y

x z

Figure 1.2 Orientation of three p-orbitals.

Table 1.2 (Continued)

c d-subshell consists of fve orbitals that are known as d xy d yz, d xz, d x2 −y2 and d z2 which are shown in Figure 1.3.

Figure 1.3 Orientation of fve d-orbitals.

Note:

(i) d xy , d yz , d xz orbitals are known as non-axial d-orbitals because the lobes of the orbitals are not

available along the axis

(ii) dx2 −y2 and d z2 are known as axial d-orbitals because the lobes of oribtals are along the axis.

4 Spin Quantum Number (s or m s): It is the quantum number which is required to describe an electron only (not the orbital) and it characterizes the spin of an electron An electron is not only moving around the nucleus but also spinning about its own axis It may spin either clockwise or anticlockwise

a The possible values of spin quantum number are +1 2/ and −1 2/ , but it is not fxed, that is, if the value

of s is +1 2/ for clockwise spinning, then the value of s is −1 2/ for anticlockwise and vice-versa Also, the electrons present in parallel spin must have the same spin value, for example,

or

or

s s

=

=

−+

−+

−+

1.3 Electronic Configuration of an Atom 7

5g 6p

7p 8p

7s 8s 6s

4p 5p

4f 5d 6d

4d 3d

2p 3p

Figure 1.4 Sequence of flling of energy levels

Alternatively, the above energy sequence or the energy comparison between any two subshells can be

established very easily on the basis of (n + l) rule which is stated as follows:

1 Smaller the value of (n + l) for a particular subshell smaller will be its energy.

2 If for two subshell, the (n + l) value is the same then the subshell having higher value of n will have

higher energy For example,

forand for same

Between the two, 4p has higher energy as compared to that of 3d.

Let us compare the energy of the following subshells according to (n + l) rule:

5p, 4s, 4d, 3d, 4f, 6s Based on the (n + l) rule, we have

Subshell (n + l ) 5p 5 + 1 = 6

Pauli exclusion principle

We have seen that three quantum numbers n, l and m are needed to defne an orbital Each orbital may

hold up to two electrons, provided they have opposite spins Thus, an extra quantum number is required to defne the spin of an electron in an orbital Thus four quantum numbers are needed to defne the energy of

an electron in an atom

The Pauli’s exclusion principle states that no two electrons in one atom can have the same values of all four quantum numbers or an orbital in a subshell can accommodate a maximum of two electrons of opposite spin.

Based on the above rule, the number of electrons which can be accommodated in each main energy level can be calculated by permuting the quantum numbers, as shown in Table 1.3

Table 1.3 Maximum number of electrons in a shellShell number

n (Principal

quantum number)

Possible number

of orbitals in a subshell

Possible number

of orbitals in a shell

Maximum number of electrons present

0 –1

+ 1 0 –1 –2

0 –1

+ 1 0 –1 –2

(Continued)

1.3 Electronic Configuration of an Atom 9

Shell number

n (Principal

quantum number)

Possible number

of orbitals in a subshell

Possible number

of orbitals in a shell

Maximum number of electrons present

in a shell

+ 2 + 1 0 –1 –2 –3

Note:

(i) The number of orbitals present in a subshell is (2l + 1)

(ii) The total number of electrons present in a subshell is 2(2l + 1)

(iii) Total number of orbitals present in a shell is n2

(iv) Total number of electron present in a shell is 2n2.Based on the above rules, let us fnd the number of subshell, orbitals and maximum number of electrons

that can be accommodated in R shell.

Shell K L M N O P Q R

= 1 2 3 4 5 6 7 8

n

Hence, for R shell, n = 8.

The number of subshell = 8 (i.e 0, 1, 2, 3, 4, 5, 6, 7)

The number of orbitals in this shell = 82 = 64

The maximum number of electrons that can be accommodated in this shell = 2n2 = 2 × 64 = 128

where S = total spin value of all electrons in degenerate orbitals.

For example, consider the nitrogen atom; the electronic distribution is shown as follows:

7N : 1s2 2s2 2p3 M = 2|S| + 1

(correct) S = 1/2 + 1/2 + 1/2 = 3/2 M = 4 (wrong) S = + 1/2 − 1/2 −1/2 =−1/2 M = 2

(correct) S = − 1/2 − 1/2 − 1/2 = − 3/2 M = 4

(wrong) S = + 1/2 − 1/2 + 1/2 = 1/2 M = 2

Table 1.3 (Continued)