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Trang 2Pearson 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.
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About Pearson
Trang 4A.K Singhal U.K Singhal
A Complete Resource Book in
chemistry
Trang 5my grandparents, parents and teachers
Published by Pearson India Education Services Pvt Ltd, CIN: U72200TN2005PTC057128
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prior written consent
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Trang 6Preface vii
Acknowledgements viii
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 Purifi cation and Characterization of Carbon Compounds 22.1–22.26
Contents
JEE Mains 2018 Paper xi
JEE Mains 2017 Paper xviii
Trang 7Chapter 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
Trang 8About 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 qualifi ed 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 suffi cient 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 eff orts, 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
singhal.atul50@yahoo.com or singhal.atul1974@gmail.com.
A.K Singhal
Trang 9The 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
honour-able 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 aff ection 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
Acknowledgements
Trang 1018 Chemistry of Heavier Elements (Metallurgy) – 1 – – – 2 – 1 1 2 – –
19 Transition Metals Including Lanthanides and Actinides – 1 2 – 2 – 2 – 1 1 – –
Trang 11Purification and Characterization of Carbon Compounds
26
Organic Compounds with Functional Groups Containing Halogens (X)
28 Organic Compounds Containing Oxygen-II – – 1 – 2 1 1 1 1 1 1 1
29
Organic Compounds with Functional Groups Containing Nitrogen
31 Biomolecules and Biological Processes – 1 1 1 1 2 1 1 1 1 1
Total No of Questions 33 38 30 28 30 30 29 22 21 34 35 30
Trang 121 For 1 molal aqueous solution of the following
com-pounds, which one will show the highest freezing
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 O and (H O OH )2 2 + −
(B) (H O + O2 2) and H2O
(C) (H O2 +O2) and (H O2 +OH−)
(D) H O and (H O O )2 2 + 2
3 Which of the following compounds will be suitable for
Kjeldahl’s method for nitrogen estimation?
4 Glucose on prolonged heating with HI gives:
(A) 6-iodohexanal (B) n-Hexane
(C) l-Hexene (D) Hexanoic acid
5 An alkali is titrated against an acid with methyl
orange as indicator, which of the following is a correct
combination?
Base Acid End point
(A) Strong Strong Pink to colourless
(B) Weak Strong Colourless to pink
(C) Strong Strong Pinkish red to yellow
(D) Weak Strong Yellow to pinkish red
6 The predominant form of histamine present in human
(B)
NH2
N
N H
8 Which of the following lines correctly show the
tem-perature dependence of equilibrium constant K, for anexothermic reaction?
1 T(K)
(A) A and D (B) A and B (C) B and C (D) C and D
Trang 139 How long (approximate) should water be
electro-lyzed by passing through 100 amperes current so that
the oxygen released can completely burn 27.66 g of
(III) Only one isomer is produced if the reactant
com-plex ion is a trans-isomer
(IV) Only one isomer is produced if the reactant
com-plex ion is a cis-isomer
The correct statements are:
(A) (II) and (IV) (B) (I) and (II)
(C) (I) and (III) (D) (III) and (IV)
11 Phenol reacts with methyl chloroformate in the
pres-ence of NaOH to form product A A reacts with Br2 to
form product B A and B are respectively:
(A)
OH
O OCH3
OH and
O Br
OCH3
(B)
OH
O OCH3
OH and
O Br
O and
(D)
O O
O Br
O and
12 An aqueous solution contains an unknown
concentra-tion 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+?
(A) 1.0 × 10-10 M (B) 5 × 10-9 M
(C) 2 × 10-9 M (D) 1.1 × 10-9 M
13 At 518°C the rate of decomposition of a sample of
gas-eous 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:
14 The combustion of benzene (1) gives CO2 (g) and
H2O (l) Given that heat of combustion of benzene atconstant volume is -3263.9 kJ mol-1 at 25°C; heat ofcombustion (in kJ mol-1) of benzene at constant pres-
sure will be: (R = 8.314 JK-1 mol-1)(A) -3267.6 (B) 4152.6
15 The ratio of mass percent of C and H of an organic
compound (CxHyOz) is 6 : 1 If one molecule of theabove compound (CxHyOz) contains half as much oxy-gen as required to burn one molecule of compound
CxHy completely to CO2 and H2O, then empirical mula of compound CxHyOz is:
for-(A) C2H4O3 (B) C3H6O3(C) C2H4O (D) C3H4O2
16 The trans-alkenes are formed by the reduction of
alkynes with:
(A) Sn-HCl (B) H2-Pd/C, BaSO4(C) NaBH4 (D) Na/liq NH3
17 Which of the following are Lewis acids?
(A) BCl3 and AlCl3 (B) PH3 and BCl3(C) AlCl3 and SiCl4 (D) PH3 and SiCl4
18 When metal ‘M’ is treated with NaOH, a white
gelat-inous precipitate ‘X’ is obtained, which is soluble inexcess of NaOH Compound ‘X’ when heated stronglygives an oxide which is used in chromatography as anabsorbent The metal ‘M’ is:
19 According to molecular orbital theory, which of the
following will not be a viable molecule?
Trang 1421 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:
(A)
O O
(C)
O O
CO2H
CH3
(D)
CH3OH
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
24 The major product of the following reaction is:
Br
MeOH NaOMe
(A)
OMe
25 The compound that does not produce nitrogen gas by
the thermal decomposition is:
(A) (NH4)2SO4 (B) Ba(N3)2 (C) (NH4)2Cr2O7 (D) NH4NO2
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) 5 10× − 19 (B) 5 10× − 8 (C) 3 10× − 20 (D) 6 10× − 21
27 The oxidation states of Cr in [Cr(H O) Cl2 6] 3,[Cr(C H )6 6 2]
Cr(H O) Cl2 6 3 Cr(C H )6 6 2
[ ] ,[ ] and K Cr(CN) (O) (O )(NH )2[ 2 2 2 3 ] re
-spectively are:
(A) +3, 0 and +4 (B) +3, +4 and +6 (C) +3, +2 and +4 (D) +3, 0 and +6
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 converting3Ca (PO ) Ca(OH)3 4 2 2
(A) 3 Ca(OH) CaF{ 2} 2
(B) [CaF2]
(C) [3(CaF2).Ca(OH)2]
(D) [3Ca (PO ) CaF3 4 2 2]
29 Which of the following salts is the most basic in
Trang 151 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 O 2 2 acts as an oxidant as follows
Oxidation number decreases
Oxidation number increases
In alkaline medium, H O 2 2 acts as reducing agent as follows
Oxidation number increases
Oxidation number decreases
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
C H NH6 5− 2 is suitable for the test.
Hence, the correct option is (C).
4 Glucose on heating with HI gives n-hexane as followed
Hence, the correct option is (B).
5 As methyl orange is weak organic base So it is used in the
titration of weak base (NH4OH) vs strong acid (HCl)
Unionized form (Yellow) Ionized form(Red)
unproton-Hence, the correct option is (A).
Answer keys
1 (A) 2 (D) 3 (C) 4 (B) 5 (D) 6 (A) 7 (D) 8 (B) 9 (D) 10 (C)
11 (D) 12 (D) 13 (B) 14 (A) 15 (A) 16 (D) 17 (A) or (C) 18 (D) 19 (A) 20 (A)
21 (B) 22 (D) 23 (D) 24 (C) 25 (A) 26 (C) 27 (D) 28 (D) 29 (C) 30 (D)
Hints and solutions
7 Order of basicity in increasing order is as follows
Trang 16Here (III) is most basic because its conjugate acid is
stabi-lized by equivalent resonance.
Out of (I) and (IV), (IV) is more basic due to + I effect of
-CH 3 group (II) is less basic than (I) and (IV) because N
atom is sp 2 (more s%) hybridized.
Hence, the correct option is (D).
As according to the balanced equation:
Here 27 66 g B H 2 6 , i.e., 1 mole B H 2 6 requires 3 mole of
O2 Here this oxygen is produced by electrolysis of water as
follows.
2 H O 2 →4F 2 H 2 + O 2
As 1 mole O2 is produced by 4 F charge
So 3 mole O2 will be produced by 12 F charge
trans-isomer mer-isomer (only)
Br Br + Br
NH3
NH3
H3N Co
Br Br
NH3
NH3
Br
H3N Co
Br −
Br −
Hence, the correct option is (C).
11 The sequence of the reaction is as follows
OPh
O O
O CH3
OMe O
Br (Major product) (B)
o, p-directing group
(A) C
For BaSO4 Ksp is given as
K (BaSO ) = [Ba ][SO ] sp 4 +2 4 −
10 − 10 = [Ba ] + 2 × 0 1
[Ba ]+2 = 10 M (in 500 mL solution)−9
[SO ] 4 − in 500 mL solution will be
Trang 17.
Hence, the correct option is (A).
15 As ratio of mass percent of C and H in CxHyOz is 6 : 1.
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).
Now oxygen needed to burn CxHy
Hence, the correct option is (A) (C 2 H4O3).
16 Na/liq NH3 reduces alkynes into trans alkene (trans or anti
addition).
R C C R
C = C R
R Na/liq NH3
trans alkene
H
H 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
Hence, the correct option is (D).
19 Species Bond order
2 2 1 0 5. (exists)
As H2− has bond order as zero, so it cannot exist.
Hence, the correct option is (A).
20 It follows SN1 reaction as follows.
O
O
Δ HI
CH3
O
CH3
CH3H H
CH3
⊕
OH + +
Trang 1821 Here Asprin is formed as follows
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
H H
H H
Hence, the correct option is (D).
23 As in Frenkel defect, smaller ion (cations) displaces from its
actual lattice site into the interstitial sites.
Hence, the correct option is (D).
24 It follows E2 mechanism as follows
Br H
+ NaBr + MeOH
MeOH NaOMe
Hence, the correct option is (C).
25 Here (NH4)2SO4 an heating gives Ammonia while rest give N2.
Hence, the correct option is (C).
27 The oxidation states of Cr are 3, 0, 6, respectively.
Compound Oxidation states of Cr
28 3Ca (PO ) Ca(OH) F
3Ca (PO ) CaF 2OH
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.
Hence, the correct option is (C).
30 I3− has 3 lone pair e- as follows
I I− I Hence, the correct option is (D).
Trang 191 Which of the following compounds will give
signif-icant amount of meta product during mono-nitration
2 ∆U is equal to:
(A) Isochoric work (B) Isobaric work
(C) Adiabatic 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) (B) (II) < (I) < (III)
(C) (I) < (III) < (II) (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)
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:
6 The formation of which of the following polymers
involves hydrolysis reaction?
(C) Nylon 6, 6 (D) Terylene
7 The most abundant elements by mass in the body of a
healthy human adult are:
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:
(C) 7.5 kg (D) 10 kg
8 Which of the following, upon treatment with
tert-BuONa followed by addition of bromine water, fails todecolourize the colour of bromine?
(A)
O 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 onheating
11 3-Methyl-pent-2-ene on reaction with HBr in presence
of peroxide forms an addition product The number ofpossible stereoisomers for the product is:
12 A metal crystallises in a face centred cubic structure.
If the edge length of its unit cell is ‘a’, the closestapproach between two atoms in metallic crystal will be:
Trang 20R1 and R2 respectively at 300 K, then ln(k2/k1) is equal
to (R = 8.314 J mol-1K-1):
14 The correct sequence of reagents for the following
conversion will be:
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?
(A) CH2OH
OCOCH3HO
OH
(B) CH2OH
HO OH
(C) CH2OH
OCH3HO OH
(D)
CH2OH
OH OH OH
C(graphite)+2H g2( )→CH g4( ) will be:
(A) +74.8 kJ mol-1 (B) +144.0 kJ mol-1 (C) -74.8 kJ mol-1 (D) -144.0 kJ mol-1
18 Which of the following reactions is an example of a
redox reaction?
(A) XeF4+O F2 2→XeF6+O2 (B) XeF2+PF5→[XeF PF]+ 6− (C) XeF6+H O2 →XeOF4+ 2HF (D) XeF6+2H O2 →XeO F2 2+4HF
19 The products obtained when chlorine gas reacts with
cold and dilute aqueous NaOH are:
(A) ClO and ClO− 3− (B) ClO and ClO2− 3− (C) Cl and ClO− − (D) Cl and ClO− 2−
20 The major product obtained in the following reaction
is:
Δ BuOK
Br H
C6H5
C6H5
(A) ( )± C H CH O Bu CH CH H6 5 ( t )
2 6 5 (B) C H CH=CHC H6 5 6 5
Trang 2121 Sodium salt of an organic acid ‘X’ produces
efferves-cence 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
(C) CH3COONa (D) Na C O2 2 4
22 Which of the following species is not paramagnetic?
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
25 On treatment of 100 ml of 0.1 M solution of COCl3
6H2O with excess AgNO3; 1.2 × 1022 ions are
precipi-tated The complex is:
(D) Only SO4−
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:
(D) O , F , Na , Mg− − + 2+
Trang 221 Nitration is carried out in presence of concentrated HNO3
and concentrated H2SO4 Here, aniline acts as base, in
pres-ence of H2SO4 its protonation takes place and anilinium ion
Anilinium ion is strongly deactivating group and meta
directing in nature so it gives meta nitration product in
sig-nificant amount (≈ 97%).
NH2
NO2
+conc.HNO3conc.H2SO4
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
dissocia-tion of alkyl halide
−
= 7+ (3.2)1 (3.4)
2
1 2
−
= 6 9
6 Formation of Nylon6 involves hydrolysis of its monomer
(caprolactum) in initial state as follows:
Hydrogen = 10.0% and Nitrogen = 2.6%
Total weight of person = 75 kg
Mass due to 1H is = 75 × 10 =
100 7 5 kg
1 H atoms are replaced by 2 H atoms.
Hence, mass gain by person = 7.5 kg
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
Trang 23JEE Mains 2018 Papers xiii
8
Br
(fails to decolorize the colour of bromine) (no unsaturation)
tert-BuONa
O
O-tBu O
C6H5
(it decolorizes bromine solution)
to unsaturation)
tert-BuONa
Br O
(it decolorizes bromine solution due
(a) ZnO + Na2O → Na 2 ZnO2
acid base salt
(b) ZnO + CO2 → ZnCO 3
base acid salt
10 Mg can form basic carbonate like,
2
3
(4 stereo isomers possible due to 2 chiral centres as molecule is asymmetric )
H
(II)
CH3
Et H
H Br
H3C
CH3
CH3
H Br
H
CH3
H
Br H
H3C
(I) Et
CH3
Br H
H
(II) Et H
H Br
H
(IV)
CH3
Et H
Br H
(E E RT
(E E RT
2 1
CH3MgBr
[Ag(NH3)2]OH Tollens reagent
O
C O
CH3
CH3
H3C OH
HO
C
15 It is factual.
16 (i) Ester in presence of aqueous KOH solution give SNAE
reaction so following reaction takes place.
Trang 24O—C—Me O
O CH2OHHOCH2
O
OH O
O CH2OHHOCH2
− + Me—C—O−
SN AE
Aq KOH
Reagent Tollen’s
Ring opening Hemiketal
O
OH
CH2OH HOCH2 O−
⊕ve silver mirror test
(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.
Here, xenon undergoes oxidation while oxygen undergoes
reduction (Redox Process)
19 Cl2 + 2OH − Cl + ClO − + H2O
[cold and dilute]
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.
C6H5
C6H5+ t BuOH + Br ⊕
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:
(C)
N pyridine is aromatic (6πe - )
25 Moles of complex =Molarity volume ml× ( )
1000
=100 0 1× =
1000 0 01. . mole
Moles of ions precipitated with excess of AgNO3
.
= 0 02 moles
Trang 25Number of Cl−present in ionization sphere =
Moleof ion precipitated with exess AgNO
Mole of complex
3 =0 02
0 0
11 =2
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
corre-sponding aldehyde (partial reduction).
27 NO3− : The maximum limit of nitrate in drinking water can
be 50 ppm Excess nitrate in drinking water can cause
dis-eases like methemoglobinemia, etc.
SO4− : above 500 ppm of SO4− ion in drinking water causes
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 4 − and
NO 3 − in water is suitable for drinking but the concentration
of F− (i.e., 10 ppm) makes water unsuitable for drinking
Trang 27Matter and its nature, Dalton’s atomic theory, Concept of atom, Molecule, Element, Compound, Precision,
Significant figures, SI units, Derived units, Laws of chemical combinations, Mole, Mass, Molecular mass,
Equivalent mass, Chemical equation, Stoichiometry of chemical equation and various levels of multiple-choice
questions
MATTER
Any species having mass and occupying space is known
as matter It can exist in the three physical states, namely,
solid, liquid and gas
Figure 1.1 Classification of Matter
Pencil, air, water, justify the physical states and are all
composed of matter
• At the bulk level or macroscopic level, we can
fur-ther classify matter as mixtures or pure substances
Mixture
A mixture is composed of two or more substances which
are known as its components or constituents (in any ratio)
The components of the mixture can be separated with the help of physical separation methods like filtration, crystal-lization, distillation
• A mixture is further classified into two categories—
homogeneous and heterogeneous
• In a homogeneous mixture all the components under-
go complete mixing forming a uniform composition
as, air or sugar solution
• In a heterogeneous mixture the composition formed due to the mixing of components is not entirely uniform like in the case of grains mixed with dust etc
Pure Substance
Pure substances have fixed compositions and their uents cannot be separated by using simple physical meth-ods of separation
constit-• A pure substance can be further classified into an ment or a compound
ele-• An element is composed of one type of particle
which could either be atoms or molecules Na, Cu,
Ag have only one type of atoms
• A compound is formed by the combination of two or
more atoms or different elements For example, H2O,
Trang 28Dalton’s Atomic Theory
An atom is the smallest particle of an element which is
neutral in nature, retains all the properties of the element
and takes part in a chemical reaction The word atom was
introduced by Dalton (alamos means undivided)
The Dalton’s atomic theory was proposed by Dalton on
the basis of laws of chemical combination
Main assumptions
• Matter (of any type) is composed of atoms
• An atom is the smallest, fundamental, undivided
particle (Building block material)
• An atom can neither be created nor destroyed
• Atoms of an element have similar size, energy and
properties while atoms of different element differ in
these aspects
• Atoms combine in whole number ratios to form a
molecule, therefore, a molecule is the smallest
iden-tity that exists individually
Modern view about atom
According to the modem view:
• An atom is divisible into other smaller particles
which are known as subatomic particles It can also
combine in non-whole number ratio as in the case
of non- stoichiometric compounds (Berthollide
com-pounds) like Fe0.93O
• Atoms of same element also differ in mass and mass
related properties as in the case of isotopes
• Chemical reactions involve rearrangement of atoms
Molecule
The term molecule was introduced by Avogadro It is the
smallest particle (identity) of matter that can exist
inde-pendently and retains all the properties of the substance
Normally the diameter of the molecules is in the range of
4–20 Å and the molecular mass is between 2–1000
• In case of macromolecules, the diameter is in the
range of 50–250 Å and the molecular weight may be
in lakhs
Berzelius Hypothesis
According to the Berzelius hypothesis, “Equal volumes
of all the gases contain same number of atoms under the
similar conditions of temperature and pressure.”
This hypothesis on application to law of combining
volume confirms that atoms are divisible which is in
con-trary to Dalton’s theory
PHYSICAL QUANTITIES AND THEIR MEASUREMENTS
In order to describe and interpret the behaviour of ical species, we require not only chemical properties but also few physical properties Physical properties are mass, length, temperature time, electric current etc
Further, to express the measurement of any physical quantity we require its numerical value as well as its unit
Hence, the magnitude of a physical quantity can be given as Magnitude of physical quantity 5 Its numerical value 3 Unit
Precision and Accuracy
• The measurements are considered accurate when the age value of different measurements is closer to the actual value An individual measurement is considered more accurate when it differs slightly from the actual value
aver-• When the values of different measurements are close
to each other as well as to the average value, such measurements are called precise
• In fact, precision is simply the measurement of reproductability of an experiment
Significant Figures
These are some uncertainties in values during ment of matter In order to make accurate measurements
measure-we use these figures
The total number of digits in a number including the last digit with uncertain value is known as the number of significant figures, for example, 14.3256 6 0.0001 has six significant figures
Rules to determine significant numbers
• All non-zero digits as well as the zeros present between the non-zero digits are significant, for exam-ple, 6003 has four significant figures
• Zeros to the LHS of the first non-zero digit in a given number are not significant figures, for example, 0.00336 has only three significant figures
• In a number ending with zeros, if the zeros are ent at right of the decimal point then these zeros are also significant figures, for example, 33.600 has five significant figures
pres-• Zeros at the end of a number without a decimal are not counted as significant figures, for example,
12600 has just three significant figures
• The result of division or multiplication must be reported to the same number of significant figures
as possessed by the least precise term, for example, 3.331 3 0.011 5 0.036641 ≈ 0.037
Trang 29• The result of subtraction or addition must be reported
to the same number of significant figures as
pos-sessed by the least precise term, for example, 5.1 1
7.21 1 8.008 5 20.318 ≈ 20.3
Rounding-off non-significant figures
Rounding-off non-significant figures means dropping of
the uncertain or non-significant digits in a number It is
possible as follows:
• If the rightmost digit to be rounded-off is 5, then
the preceding number is increased by one, for
exam-ple, 3.17 is rounded off to 3.2
• If the rightmost digit to be rounded-off is, 5, then the
preceding number is kept unchanged, for example,
5.12 is rounded off to 5.1
• If the rightmost digit to be rounded-off is equal to
5, the preceding number is kept as such in case of
an even value However, in case of an odd value it is
increased by one, for example, 4.45 is rounded-off to
4.4; 5.35 is rounded off to 5.4
Exponential notation or scientific notation
In case a number ends in zeros that are not to the right of
decimal point it is not essential that zeros are significant
For example, 290 has 2 or 3 significant figures and 19500
has 3, 4 or 5 significant figures
This confusion can be removed when the values are
expressed in terms of scientific notations, for example, 19500
can be written as 1.95 3 104 (3 significant figures), 1.950 3
104 (4 significant figures), 1.9500 3 104 (5 significant
fig-ures) In this kind of notation, every number can be written as
N 5 Number with non-zero digit
to the left of the decimal point
For example, 0.00069 can be expressed as 6.9 3 1024
2 2
5 kg m 2 1 sec 2 2 5 Pascal (Pa)
5 kg m 2 sec 2 2 5 Joule
Plane angle (Radian, that is, ‘rad’)
Solid angle (Steradian, that is, ‘str’)
Trang 30LAWS OF CHEMICAL COMBINATIONS
Law of Conservation of Mass
• Law of conservation of mass was proposed by Lavoisier
in 1774
• It was verified by Landolt
• According to this law, “In a chemical change the
total mass of the products is equal to the total mass
of the reactants, that is, mass is neither created nor
destroyed.” For example, when a solution with
calcu-lated weight of AgNO3 and NaCl is mixed, white
pre-cipitates of AgCl are formed while NaNO3 remains
in solution The weight of the solution remains the
same before and after this experiment
• It is not applicable to nuclear reactions
Law of Constant Composition or Law of
Definite Proportion
• Law of constant composition was proposed by Proust
in 1779
• It was verified by Star and Richards
• According to this law, “A chemical compound always
contains same elements combined together in same
proportion by mass.” For example, NaCl extracted
from sea water or achieved from deposits will have
23 g Na and 35.5 g of chlorine in its one mole
• It is not applicable to non-stoichiometric compounds
like Fe0.93 O
Law of Multiple Proportion
• Law of multiple proportion was proposed by Dalton
in 1804
• It was verified by Berzilius
• According to this law, “Different weights of an ment that combine with a fixed weight of another element bear a simple whole number ratio.” For example, in case of CO, and CO2 weight of oxygen which combines with 12 g of carbon is in 1 : 2 ratio
ele-• It is applicable when same compound is prepared from different isotopes of an element For example,
H2O, D2O
Law of Reciprocal Proportion
• Law of reciprocal proportion was proposed by Richter in 1792
• It was verified by Star
• According to this law, “When two different elements undergo combination with same weight of a third element, the ratio in which they combine will either
be same or some simple multiple of the ratio in which they combine with each other.”
• It is also known as Law of equivalent proportion
which states “Elements always combine in terms of their equivalent weight.”
Law of Combining Volume
• Law of combining volume was proposed by Gay-Lussac
• It applies to gases
• According to this law, “When gases react with each other they bear a simple whole number ratio with one another as well as the product under conditions of same temperature and pressure.”
AVOGADRO’S LAW
• Avogadro’s law explains law of combining volumes
• According to this law “Under similar conditions
of temperature and pressure equal volume of gases contain equal number of molecules.”
• It is used in:
1 Deriving molecular formula of a gas
2 Determining atomicity of a gas
3 Deriving a relation Molecular mass 5 2 3 Vapour Density (M 5 2 3 V.D.)
4 Deriving the gram molecular volume
Trang 31• Avogadro number (N0 or NA) 5 6.023 3 1023.
• Avogadro number of gas molecules occupies
22.4 litre or 22400 mL or cm3 volume at STP
• The number of molecules in 1 cm3 of a gas at STP is
equal to Loschmidt number that is, 2.68 3 1019
• Reciprocal of Avogadro number is known as
avogram
MOLE
• Mole is a unit which represents 6.023 3 1023
par-ticles, atoms, molecules or ions etc., irrespective of
their nature
• Mole is related to the mass of substance, the volume
of gaseous substance and the number of particles
• Volume of one mole of any gas is equal to 22.4 litres
or 22.4 dm3 at STP It is known as molar volume
• Mole 5W
M
5 Molar mass of substance (g.m.m.)Wt of substance in g _
Here, g.m.m 5 Gram molecular mass
Mole 5 Vol of substance in litre 22.4 L
Mole Concept: An Example
A mole of any substance (like N2) stands for:
• 6.023 3 1023 molecules of N2
• 2 3 6.023 3 1023 atoms of nitrogen
• 28 g of nitrogen
• 22.4 litre of N2 at STP
To find total number of identities
⇒ Total Number of Molecules = mole (n) × NA
⇒ Total Number of Atoms in = mole (n) × NA ×
No of atoms present in one molecule
⇒ Total Number of Electrons = mole (n) × NA ×
No of electrons in one molecule
⇒ Total Charge on Any Ion = mole (n) × NA × charge on
• The atomic mass of any element expressed in grams
is called g.a.m (gram atomic mass) or gram atom
• A gram atom has number of atoms of the element
Atomic mass 5 E 3 V Here, E 5 Equivalent weight
Average atomic mass
Molecular Mass
Molecular mass represents the total mass of a molecule, that is, number of times a molecule is heavier than 1
12weight of C–12 atom or 1
16 weight of an oxygen atom
• It is non-variable
Determination of molecular mass
Vapour density method
Mol mass 5 2 3 V.D
V.D 5 Volume at STP (in mL) W 3 22400 _
Here, W 5 Weight of substance in g V.D = Vapour Density
Trang 32Graham’s diffusion method
r
r =
MM
1 2
2 1
Here r1, r2 are rates of diffusion/effusion for two species
while M1, M2 are their molecular masses respectively
Colligative properties method
pV 5 W _ m RT Here, p 5 Osmotic pressure in atm
• Equivalent weight is the weight of an element or a
compound which will combine with or displace
1.008 part by weight of H2 or 8 part by weight of O2
or 35.5 part by weight of Cl2
• Equivalent weight is a number and when it is denoted
in grams, it is called gram equivalent.
• It depends upon the nature of chemical reaction in
which substances take part
Methods to Find Equivalent Weight
For acids E = protocity or basicity of acid Molecular weight _
For example, for H3PO4, E = M 3
For H2SO4, E = M 2 (Also for H2C2O4 · 2H2O)
For bases E = Acidity or number of OHMolecular weight 2 ions
For example, for Ca(OH)2, E = M 2
For Al(OH)3, E = M3
or
Fe(OH)3
For ions E = Molecular weightCharge on ion _
For example, for SO 42 2, E = M 2
For P O 43 2
, E = M3
For compounds
E = Valency of cation or anion Molecular weight
For example, for CaCO3, E = M 2 For AlCl3, E = M 3
Na3PO4, E = M 3
For redox reactions
=
E Molecualr weightTotalchange in oxidation number Let’s take KMnO4 as an example
2KMnO4 1 2KOH 2K2MnO4 1 H2O 1 [O]
one unit change in oxidation number
3 In neutral medium, E 5 M3
2KMnO4 1 H2O 2KOH 1 2MnO2 1 3[O]
3 units change in oxidation number
For acidic salts
E 5 Number of replaceable H-atoms Molecular weight
For H3PO4, for example, Ca(OH)2 1 H3PO4 CaHPO4 1 2H2O
E 5 Wt of metal Wt of oxygen 3 8 Weight of oxygen 5 Weight of metal oxide
2 Weight of metal
Trang 33(c) Chloride formation method
E 5 Wt of metal Wt of chloride 3 35.5 Weight of chloride 5 Weight of metal chloride
2 Weight of metal (d) Double decomposition method
Eq wt of salt taken
MOLE FRACTION
• Mole fraction is t he ratio of moles of one component
to the total number of moles present in the solution
It is expressed by X, for example, for a binary
solu-tion of two components A and B
and solute respectively
• Mole fraction does not depend upon temperature as
both the solute and the solvent are expressed by weight
CHEMICAL EQUATION AND
STOICHIOMETRY OF CHEMICAL
REACTIONS
1 A balanced chemical reaction represents a
stoichio-metric equation
2 In a stoichiometric equation, the coefficient of reactants
and products represents their stoichiometric amounts
3 The reactant which is completely used up during an
irre-versible reaction is called the limiting reagent while the
reactant left is called the excess reagent, for example, 20
g of calcium is burnt in 32 g of O2, then Ca is the limiting
reagent while O2 is the excess reagent
4 Stoichiometric calculations help in finding whether
the production of a particular substance is
economi-cally feasible or not
5 These stoichiometric calculations are of following
four types:
(a) Calculations based on weight–weight relationship
(b) Calculations based on weight–volume relationships
(c) Calculations based on volume–volume relationships
(d) Calculations based on weight–volume–energy relationships
6 If the amount of the reactant in a particular reaction is
known, then the amount of the other substance needed
in the reaction or the amount of the product formed in the reaction can be calculated
7 For stoichiometric calculations the following steps
must be considered:
(a) A balanced chemical equation using cal formulas of reactants and products must be written
(b) Here, the coefficients of balanced chemical tion provide the mole ratio of the reactants and products
(c) This mole ratio is convertible into weight–
weight (w/w) ratio, weight–volume (w/v) ratio
or volume–volume (v/v) ratio These are called percentage by weight, percentage by volume and percentage by strength respectively
SOLVED EXAMPLES Mole Concept
1 If 1 Faraday was to be 60230 coulombs instead of 96500
coulombs, what will be the charge on an electron?
Trang 34The volume of H2 at NTP given by Zn
5 (1.67 2 A) 22.465.4 L (ii)From (i) and (ii)
8 How many years would it take to spend Avogadro
num-ber of rupees at the rate of 10 lac rupees per second?
Solution
Avogadro number 5 6.023 3 1023
Total rupees 5 6.023 3 1023 RsRate of spending 5 10 lac rupees/s 5 106 Rs/sNumber of years to spend all the rupees
5 106 3 60 3 60 3 24 3 365 Rs/year6.023 3 1023 Rs
5 1.90988 3 1010 years
9 Oxygen is present in a one litre flask at a pressure of
7.6 3 10210 mm of Hg Calculate the number of gen molecules in the flask at 0 °C
oxy-Solution
Since, PV 5 nRT 7.6 3 10210 atm 3 1 L _ 760
5 n 3 0.0821 L atm K21 mol21 3 273 K
n 5 7.6 3 10210 L atm
760 3 0.0821 L atm K21 mol21 3 273 K
5 10 _ 22.41 212 mol Number of molecules 5 (6.02 3 1023 mol21) 3 10 _ 22.41 212 mol
5 2.68 3 1010
3 Calculate the number of atoms of oxygen present in
88 g of CO2 What would be the mass of CO having the
same number of oxygen atoms?
Solution
Number of moles of CO2 5 44 g mol88 g 21
5 2 moles
1 mole of CO2 contains 2 moles of oxygen atoms,
2 moles of CO2 will contain 4 moles of oxygen atoms
Number of oxygen atoms 5 4 3 6.023 3 1023
5 2.5092 3 1024
1 mole oxygen atom is present in 1 mole of CO,
4 moles oxygen atoms are present in 4 moles of CO
As one molecule of CH4 contains (6 1 4) 5 10
ele-ctrons, 6.02 3 1022 molecules of CH4 will have
10 3 6.02 3 1022 5 6.02 3 1023 electrons
5 How many atoms of carbon has a young man given
to his bride-to-be if the engagement ring contains 0.5
carat diamond? (1 carat 5 200 mg)
Solution
Mass of diamond (C) 5 0.5 3 200 mg
5 100 mg 5 100 3 1023 g 5 0.1 g Number of mole of C 5 12 g mol0.1 g21
5 1/120 mole Number of C atoms 5 1 120 3 6.023 3 1023
5 5.02 3 1021
6 A mixture of aluminium and zinc weighing 1.67 grams
was completely dissolved in acid and the evolved 1.69
litres of hydrogen gas was measured at 273 K and one
atmosphere pressure What was the mass of
alumin-ium in the original mixture?
Trang 3510 2.68 3 1023 moles of a solution containing an ion An1
required 1.61 3 1023 moles of Mn O 42 for the oxidation
of An1 to A O 32 in an acidic medium What is the value
of 5 N HNO3 are mixed and the volume of the mixture
is made 1000 mL by adding water Find the normality
of the resulting solution
12 How many millilitres of 0.5 M H2SO4 are needed to
dissolve 0.5 g of copper (II) carbonate?
13 50 litres of water containing Ca(HCO3)2 when
con-verted into soft water required 22.2 g Ca(OH)2
Calculate the amount of Ca(HCO3)2 present per litre
of hard water
Solution
Reaction Ca(HCO3)2 1 Ca(OH)2 2CaCO3 1 2H2O
14 The formula weight of an acid is 82 In a titration,
100 cm3 of a solution of this acid containing 39.0 g
of the acid per litre were completely neutralized
by 95.0 cm3 of aqueous NaOH containing 40.0 g of NaOH per litre What is the basicity of the acid?
Solution
Normality of NaOH 5 1 Normality of acid 5 1 3 95100 5 0.95 Suppose the equivalent mass of the acid is E
39 _ E 5 0.95
E 5 41 Therefore, basicity 5 82/41 5 2
15 One g of impure Na2CO3 is dissolved in water and the solution is made upto 250 mL To 50 mL of this made up solution, 50 mL of 0.1 N HCl is added and the mixture after shaking well required 10 mL of 0.16 N sodium hydroxide solution for complete neutralization
Calculate the per cent purity of the sample of Na2CO3
Solution
Strength of the Na2CO3 solution 5 4 g L21
Suppose the normality of Na2CO3 solution 5 Nx
As after mixing Na2CO3 and HCl solution, NaOH solution is added, so, according to the normality equation
50 3 Nx 1 0.16 3 10 5 50 3 0.1
Nx 5 0.068 N Strength (g L21) 5 Normality 3 Equivalent mass
5 0.068 3 53 5 3.6 g L21
So, purity of Na2CO3 5 3.6 3 100 _ 4
Trang 3616 Calculate the volume of water to be added to a 100 mL
of 5N solution to make it 0.01 N
Solution
According to normality equation,
N1 V1 5 N2 V2 0.01 3 V1 5 5 3 100
V1 5 5 3 100 _ 0.01 5 50000 mL
So, volume of water to be added 5 50000 2 100
17 A small amount of CaCO3 completely neutralizes
525 mL of 0.1 N HCl and no acid is left in the end
After converting all calcium chloride to CaSO4, how
much plaster of paris can be obtained?
Calculations Based on Reactions
18 Metallic tin in the presence of HCl is oxidized by
K2Cr2O7 solution to stannic chloride What volume of
decinorrnal dichromate solution would be reduced by
The reaction is as follows:
6CaO 1 P4O10 2Ca3(PO4)2
852 g P4O10 3 mol P4O10
1 mole of P4O10 neutralizes 6 moles of CaO
3 moles of P4O10 will neutralize 18 moles of CaO Mass of CaO 5 18 3 56 5 1008 g
20 Find the weight of iron which will be converted into its
oxide by the action of 18 g of steam
Solution
The reaction is 3Fe 1 4H2O Fe3O4 1 4H2
4 moles steam reacts with 3 moles Fe
1 mole (18 g) steam reacts with 3/4 moles Fe
22 What should be the weight of NaNO3 to make 50 mL
of an aqueous solution so that it contains 70 mg Na
= 13935 mg
= 13.935 g
Trang 37CONCEPTS AT A GLANCE
Giorgi introduced MKS system
π has infinite number of significant numbers
20 carat gold is a mixture having 20 parts by weight of
gold and 4 parts by weight of copper
Some substances like CuSO4.5H2O, Na2CO3.10H2O have a
tendency to lose water in air These are called efflorescent
substances and this tendency is called efflorescence.
Some solid substances like NaOH, KOH, which have a
tendency to absorb moisture greatly from air and to get
wet are called deliquescent and this tendency is called
deliquescence
Hygroscopic substances like quicklime (CaO) anhydrous
P2O5 etc., absorb moisture from air
Compounds having similar chemical composition in the
same crystalline form are called isomorphs
For example, all alums [M2SO4 M2 (SO4)3 24H2O]
Here, M = Monovalent (K)
M = Trivalent (Al) FeSO4.7H2O (Green vitriol) and ZnSO4.7H2O
Different crystalline forms of a substance are called
polymorphs and this phenomenon is called polymorphism.
For example, ZnS → Zinc blende
1
2
2 1
Here rl, r2 are rates of diffusion for two species while
M1, M2 are their molecular masses respectively
1 2 1 2
Specifi gravity = Mass of Liquid
Trang 38EXERCISES
Single Option Correct Type
1 The number of significant figures for the three
(d) All have same no.of O-atoms
4 A mole of any substance is related to
(a) number of particles
(b) volume of gaseous substances
(c) mass of a substance
(d) all of these
5 What is the weight of oxygen required for the
com-plete combustion of 2.8 kg of ethylene?
8 Boron has two stable isotopes, B10 (19%) and B11
(18%) Find the average atomic weight of boron
12 A bivalent metal has an equivalent mass of 32, the
molecular mass of metal nitrate is?
(a) 168 (b) 182 (c) 184 (d) 188
13 How many moles of potassium chlorate should be
decomposed completely to obtain 67.2 litres of gen at STP?
14 How many grams of phosphoric acid is required to
complete neutralize 120 g of sodium hydroxide?
(a) 0.98 (b) 98
15 The hydrated salt Na2CO3n H2O undergoes 63% loss
in mass on heating and becomes anhydrous The value
of n is
16 The vapour density of a mixture having NO2 and N2O4
is 27.6 The mole fraction NO2 in the mixture is (a) 1.6 (b) 0.8
(c) 2.4 (d) 0.6
17 Among the following pairs of compounds, the one that
illustrates the law of multiple proportions is (a) Cu and CuSO4 (b) CuO and Cu2O (c) H2S and SO2 (d) NH3 and NCl3
18 How many grams of KCl must be added to 75 g of
water to produce a solution with a molality of 2.25 (a) 1.257 g (b) 125.7 g
(c) 12.57 g (d) 25.14 g
Trang 3919 Normality of 0.04 M H2SO4 is
(a) 0.02 N (b) 0.01 N
(c) 0.04 N (d) 0.08 N
20 Which among the following is the heaviest?
(a) one mole of oxygen
(b) one molecule of sulphur trioxide
(c) 100 amu of uranium
(d) 44 g of carbon dioxide
21 The empirical formula of a commercial ion exchange
resin is C8H7SO3Na The resin can be used to soften
water according to the reaction Ca+2 + 2C8H7SO3Na →
(C8H7SO3)2 Ca + 2Na+ What would be the maximum
uptake of Ca+2 by the resin expressed in mole/g resin?
(a) 0.0024 (b) 0.0246
(c) 0.246 (d) 24.6
22 A boy drinks 500 mL of 9% glucose solution The
number of glucose molecules he has consumed are
[mol wt of glucose 5 180]
(a) 0.5 3 1023 (b) 1.0 3 1023
(c) 1.5 3 1023 (d) 2.0 3 1023
23 The pollution of SO2 in air is 10 ppm by volume The
volume of SO2 per litre of air is
25 The number of grams of a dibasic acid (molecular
weight 200) present is 100 mL of its aqueous solution
to give decinormal strength is
28 The molecular weight of O2 and SO2 are 32 and
64 respectively At 15 8C and 150 mm Hg
pres-sure, one litre of O2 contains ‘N’ molecules The
number of molecules in two litres of SO2 under
the same conditions of temperature and pressure
30 50 gram of calcium carbonate was completely burnt in
air What is the weight (in grams) of the residue?
33 How many moles of acidified FeSO4 can be completely oxidized by one mole of KMnO4?
34 A compound possess 8% sulphur by mass The least
molecular mass is (a) 200 (b) 400 (c) 155 (d) 355
35 The vapour density of ozone is
37 1000 g calcium carbonate solution contains 10 g
car-bonate The concentration of solution is (a) 10 ppm (b) 100 ppm (c) 1000 ppm (d) 10,000 ppm
38 One mole of CH4 contains (a) 4.0 g atoms of hydrogen (b) 3.0 g atom of carbon (c) 6.02 3 1023 atoms of hydrogen (d) 1.81 3 1023 molecules of CH4
39 The amount of O2 for me a at N.T.P by the complete combastion of 1 kg coal is?
(a) 22.4 L (b) 2240 L (c) 1866 L (d) 100 L
Trang 4040 The maximum number of molecules is present in
42 The incorrect statement for 14 g of CO is
(a) it occupies 2.24 litre at NTP
44 Which of the following statement is correct?
(a) 1 mole of electrons weighs 5.4 mg
(b) 1 mole of electrons weighs 5.4 kg
(c) 1 mole of electrons weighs 0.54 mg
(d) 1 mole of electrons has 1.6 3 10219 C of charge
45 Which of the following pairs of gases contain equal
number of molecules?
(a) CO2 and NO2 (b) CO and (CN)2
(c) NO and CO (d) N2O and CO2
46 The samples of NaCl are produced when Na combines
separately with two isotopes of chlorine Cl35 and Cl37
Which law is illustrated?
(a) Law of constant volume
(b) Law of multiple proportions
(c) Law of reciprocal proportions
48 A breakfast cereal in advertised to contain 110 mg of
sodium per 100 g of the cereal The per cent of sodium
in the cereal is (a) 0.110 % (b) 0.01 10 % (c) 11.0 % (d) 0.22 %
49 Express 145.6 L of chlorine in terms of gram moles.
(a) 6.5 g moles (b) 4.5 g moles (c) 0.65 g moles (d) 9.5 g moles
50 The number of significant figures in 306.45 and 40440
are respectively (a) 4, 5 (b) 5, 5 (c) 5, 4 (d) 4, 6
51 The quantity of PV K
BT represents the (a) molar mass of a gas
(b) number of molecules in a gas (c) mass of gas
(d) number of moles of a gas
52 Which is the correct order of micro, nano, femto and
pico here?
(a) micro < nano < pico < femto (b) pico < femto < nano < micro (c) femto < pico < nano < micro (d) femto < nano < micro < pico
53 Find the number of atoms present in 0.016 g of methane.
(a) 0.5 N0 (b) 0.05 N0 (c) N0 (d) 1.6 N0
54 15 litre atmosphere is equal to
(a) 1.515 3 108 erg (b) 15.15 3 109 erg (c) 1.515 3 1010 erg (d) 15.15 3 1012 erg
55 If equal moles of water and urea are taken in a
ves-sel what will be the mass percentage of urea in the solution?
(a) 22.086 (b) 11 536 (c) 46.146 (d) 23.076
56 Mixture X 5 0.02 mol of [Co(NH3)5SO4]Br and [Co(NH3)5Br]SO4 was prepared in 2 litre of solution
1 litre of mixture X 1 excess AgNO3 Y
1 litre of mixture X 1 excess BaCl2 Z Number of moles of Y and Z are
(a) 0.02, 0.01 (b) 0.01, 0.01 (c) 0.01, 0.02 (d) 0.02, 0.02
57 At STP the density of CCl4 vapour in g/L will be nearest to
(a) 8.67 (b) 6.87 (c) 5.67 (d) 4.26