Std. 12 Chemistry MCQs

30 Pages·2016·1.78 MB·English

Useful for all Agricultural, Medical, Pharmacy and Engineering Entrance Examinations
held across India.

STD XII Sci.
.

Triumph Chemistry

Based on Maharashtra Board Syllabus

Fourth Edition: May 2015

Salient Features

• Exhaustive subtopic wise coverage of MCQs
• Quick review and/or important formulae provided for all the chapters

• Hints included for relevant questions

• Various competitive exams questions updated till the latest year

• Includes solved MCQs from JEE (Main), AIPMT, MH CET 2015
• Evaluation test provided at the end of each chapter

Solutions/hints to Evaluation Test available in downloadable PDF format at

www.targetpublications.org/tp915

Printed at: Repro India Ltd., Mumbai
No part of this book may be reproduced or transmitted in any form or by any means, C.D. ROM/Audio Video Cassettes or electronic, mechanical
including photocopying; recording or by any information storage and retrieval system without permission in writing from the Publisher.

P.O. No. 1072

TEID : 915
Preface

“Std. XII: Sci. Triumph Chemistry” is a complete and thorough guide to prepare students for competitive
level examinations. This book not only assists students with MCQs of Std. XII but also helps them to prepare for JEE,
AIPMT, AIIMS, AFMC, CET and various other competitive examinations.
The content of this book is based on the Maharashtra State Board Syllabus. Quick Review which summarizes
the important concepts of the entire chapter is provided for all the chapters. Formulae that form a vital part of MCQ
solving are provided for relevant chapters. Shortcuts provide easy and less tedious solving methods.
MCQs in each chapter are divided into three sections:
Classical Thinking: consists of straight forward questions including knowledge based questions.

Critical Thinking: consists of questions that require understanding of the concept and the applications of the same.

Competitive Thinking: consists of questions from various competitive examinations like JEE, AIPMT, AIIMS,
AFMC, CET, CPMT, etc.
Hints (i.e., complete solutions broken down to the simplest form possible) have been provided to the MCQs.
An Evaluation Test has been provided at the end of each chapter to assess the level of preparation of the
student on a competitive level.
In order to understand how chemistry plays an important role in our day to day life, we have made an attempt to
illustrate the same in the form of images/visuals in the related chapters.
The journey to create a complete book is strewn with triumphs, failures and near misses. If you think we’ve
nearly missed something or want to applaud us for our triumphs, we’d love to hear from you.
Please write to us on : [email protected]

Best of luck to all the aspirants!

Yours faithfully
Authors

Sr. No. Topic Name Page No.
1 Solid State 1
2 Solutions and Colligative Properties 28
3 Chemical Thermodynamics and Energetics 71
4 Electrochemistry 112
5 Chemical Kinetics 160
General Principles and Processes of Isolation of
6 193
Elements
7 p−Block Elements 217
8 d and f−Block Elements 250
9 Coordination Compounds 277
10 Halogen Derivatives of Alkanes and Arenes 314
11 Alcohols, Phenols and Ethers 361
12 Aldehydes, Ketones and Carboxylic Acids 417
13 Compounds Containing Nitrogen 464
14 Biomolecules 490
15 Polymers 513
16 Chemistry in Everyday Life 540
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Tar et Publications Pvt. Ltd. Chapter 01: Solid State

01 
Solid State 

Syllabus

1.0 Introduction
Valuable defective materials !!!!
1.1 Classification of solids
1.2 Classification of crystalline solids
1.3 Unit cell, two and three dimensional
lattices and number of atoms per
unit cell

1.4 Packing in solids
1.5 Density of unit cell
1.6 Packing in voids of ionic solids
1.7 Defects in crystal structure
1.8 Electrical properties
Do all defective materials turn up discarded?
Well …. think again. They might be present in your
1.9 Magnetic properties
jewelleries studded with precious and semi-precious
stones. These stones with eye-catching colour and

shine are due to their crystalline structure with
presence of trace quantities of mostly transition
elements which are generally called as impurities.

One such example is corrundum (Al O ) an
2 3
important mineral of aluminium. The gemstone
varieties of this mineral are ruby, sapphire, etc.

Ruby (Red) contains AlO and Cr O
2 3 2 3
Sapphire (blue) contains AlO, FeO and TiO.
2 3 2 3 2

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Quick Review

 Classification of solids on the basis of the presence or absence of orderly arrangement of the
constituent particles:
Solids

Crystalline Amorphous

A homogeneous solid in which the constituent Substances that appear like solids but do not have well
particles are arranged in a definite geometric
developed perfectly ordered crystalline structure.
pattern.
eg. Tar, glass, plastic, rubber, butter, etc.

Isomorphous Form Polymorphous Form (Allotropes)
Two or more substance having same A single substance crystallising in two or more
crystal structure. forms under different conditions.
eg. i. NaF and MgO eg. i. Graphite and diamond
ii. K SO and K SeO ii. Rhombic sulphur and Monoclinic sulphur
2 4 2 4
iii. NaNO and CaCO iii. Polymorphic forms of calcium carbonate
3 3
iv. Cr O and Fe O and silicon dioxide
2 3 2 3

 Classification of crystalline solids based on different binding forces:

Crystalline Solids

Molecular solids Ionic solids Metallic solids Covalent solids

Constituent particles are Constituent particles Formed by atoms Formed by chemical

molecules of the same are ionic molecules. of the same metallic (covalent) bonds between the

compound. eg. NaCl, ZnS, CuCl elements. neighbouring constituent

eg. Copper, gold atoms of non-metallic solids.

eg. diamond, graphite and

fullerene

Polar molecular solids Non-polar molecular solids Hydrogen bonded molecular

Constituent particles are Constituent particles are non-polar solids

covalently bonded molecules. molecules and weakly polar molecules. Molecules are held together by

eg. HCl, SO at low eg. CO , H , Cl , CH at very low hydrogen bonds.
2 2 2 2 4
temperature and high pressure temperatures eg. Solid ice

 Three types of cubic lattices:
Cubic lattice

Simple Body centered Face centered

Lattice points at eight corners Lattice points at eight corners and Lattice points at eight corners

of unit cell. one at body center of unit cell. and six face centers of unit cell.

(1 particle per unit cell) (2 particles per unit cell) (4 particles per unit cell)

(52.4% occupied space) (68% occupied space) (74 % occupied space)

eg. Polonium eg. Fe, Na eg. Cu, Al

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Tar et Publications Pvt. Ltd. Chapter 01: Solid State

 Classification of solids based on response to magnetic field:

Magnetic
Substance Characteristics Example Application
alignment
Diamagnetic  Repelled weakly in magnetic field. Benzene, Insulators
materials  All electrons are paired. NaCl, TiO
2
Paramagnetic  Weakly attracted in magnetic field. O , CuO, TiO Electronic
2
materials  Unpaired electrons are present. devices
 Permanent magnetisation is not possible.
Ferromagnetic  Strongly attracted in magnetic field. Fe, Ni, CrO is used in
2
materials  Unpaired electrons are present. Co, audio,video
 Permanent magnetisation is possible. CrO2 tapes.

Formulae

1. Density of unit cell:
z.M
d =
a3.N
0
where, a is edge of unit cell
N = Avogadro number (6.023  1023)
0
M = Molar mass
z = number of atoms per unit cell
For fcc, z = 4
for bcc, z = 2
for simple cubic, z = 1
Volumeoccupiedbyspheresinunitcell
2. Packing efficiency =  100
Volumeofunitcell
3. Radius rule and coordination number for ionic crystals:
In simple ionic crystals, the cations commonly occupy the voids or holes. The voids are empty spaces left
between anionic spheres.
r 
i. Radius Ratio  :
r 
The critical radius ratio of the void (cation) and sphere (anion), is calculated by solid geometry.
r Cation radius
 Radius ratio = =
r Anion radius
ii. Coordination Number (CN) :
The number of spheres (atoms, molecules or ions) directly surrounding a single sphere in a crystal, is
called coordination number.

4. Crystal structures of some elements and their coordination number’s (CN):

Crystal structure Example Coordination No.
bcc Li, Na, K, Rb, Cs, Ba 8
fcc or ccp Al, Ni, Cu, Ag, Au, Pt 12

5. Relation between radius ratio, coordination number and geometry :

r  Coordination Geometry Examples
Radius ratio   number
r 
0.155 to 0.225 3 Planar triangular B O
2 3
0.225 to 0.414 4 Tetrahedral ZnS
0.414 to 0.732 6 Octahedral NaCl
0.732 to 1.0 8 Cubic CsCl

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Classical Thinking 1.2 Classification of crystalline solids

8. The molecules of polar molecular solids are
1.0 Introduction held together by _______.

(A) dipole-dipole interactions
1. The physical state of matter is the result of
(B) London dispersion forces
interplay of intermolecular forces such as
_______. (C) hydrogen bonds
(A) dipole-dipole interactions (D) covalent bonds

(B) London forces
9. Which of the following is a hydrogen bonded
(C) hydrogen bonding
molecular crystal?
(D) all of these
(A) HCl (B) H
2
2. Which among the following solids is NOT (C) CH (D) Ice
soft? 4
(A) Sodium (B) Potassium 10. Ice has three dimensional crystal structure in
(C) Copper (D) Phosphorus which _________ of total volume is

unoccupied.
1.1 Classification of solids
(A) one half (B) one third
3. A crystalline solid has _______. (C) one fourth (D) one fifth

(A) long range order
11. ZnS is a / an _______ crystal.
(B) short range order
(A) ionic (B) covalent
(C) disordered arrangement
(C) metallic (D) molecular
(D) none of these

4. A solid having irregular shape is called 12. Crystals which are good conductor of
_______ solid. electricity and heat are known as _______
(A) amorphous crystals.
(B) crystalline (A) ionic (B) covalent
(C) anisotropic (C) metallic (D) molecular

(D) isomorphous
13. Which of the following is an example of
5. Amorphous substances have _______. metallic crystal solid?
(i) definite heat of fusion
(A) C (B) Si
(ii) only short range order
(C) W (D) AgCl
(iii) only long range order
(iv) indefinite heat of fusion 14. _______ solids are also called giant solids or

network solids.
(A) (i) and (iii) are correct
(A) Covalent (B) Molecular
(B) (ii) and (iii) are correct
(C) Ionic (D) Metallic
(C) (iii) and (iv) are correct
(D) (ii) and (iv) are correct
15. In graphite, carbon atoms form interlinked

6. Amorphous solids _______. _______ membered rings.
(A) possess sharp melting points (A) four (B) five
(B) exhibit anisotropy (C) six (D) seven

(C) do not undergo clean cleavage when cut
16. In fullerene, carbon atoms are _______
with knife
hybridized.
(D) possess orderly arrangement over long
(A) sp (B) sp2
distances
(C) sp3 (D) sp3d
7. Glass is a _______.
(A) supercooled liquid 17. Fullerene reacts with potassium to form
(B) crystalline solid _______.
(C) non-crystalline solid (A) K C (B) K C
39 57 37 63
(D) liquid crystal (C) K40C62 (D) K35C60

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1.3 Unit cell, two and three dimensional 25. In a close pack array of N spheres, the number
lattices and number of atoms per unit of tetrahedral holes are _______.
cell (A) 4N (B) N/2

(C) 2N (D) N
18. The three dimensional graph of lattice points
which sets the pattern for the whole lattice is 26. The number of tetrahedral voids in a unit cell
called _______. of cubical closest packed structure is _______.
(A) space lattice (B) simple lattice (A) 1 (B) 2
(C) unit cell (D) crystal lattice (C) 4 (D) 8

19. For a solid with the structure as shown in the 27. The empty space between the shared balls and
figure, the coordination number of the point B hollow balls as shown in the diagram is called
is _______. _______.
(A) 3 (A) hexagonal void
(B) 4 (B) octahedral void
(C) 5 (C) tetrahedral void
(D) 6 (D) triangular void

A B
28. In octahedral voids, _______.
20. The unit cell with the following structure (A) a simple triangular void is surrounded
refers to _______ crystal system. by four spheres
(A) cubic a (B) a bi-triangular void is surrounded by
(B) orthorhombic four spheres .
(C) tetragonal 90o 90o b c (C) a bi-triangular void is surrounded by six
spheres
(D) trigonal 90o
(D) a bi-triangular void is surrounded by
21. Which of the following are the CORRECT eight spheres

axial distances and axial angles for
29. Which of the following crystallises in bcc
rhombohedral system?
structure?
(A) a = b = c,  =  =   90°
(A) Al (B) Cu
(B) a = b  c,  =  =  = 90°
(C) Mg (D) W
(C) a  b  c,  =  =  = 90°
30. The arrangement ABCABC ……. is referred
(D) a  b  c,       90°
to as _______ close packing.
22. The number of atoms or molecules contained
(A) octahedral
in one primitive cubic unit cell is _______.
(B) hexagonal
(A) 1 (B) 2
(C) tetrahedral
(C) 4 (D) 6
(D) cubic

23. If the number of atoms per unit in a crystal is
31. In hcp arrangement, the number of nearest
2, the structure of crystal is _______.
neighbours are _______.
(A) octahedral
(A) 10 (B) 7
(B) body centered cubic
(C) 2 (D) 12
(C) face centered cubic
(D) simple cubic 1.5 Density of unit cell

1.4 Packing in solids 32. The packing efficiency in simple cubic unit

cell is _______.
24. The interstitial hole is called tetrahedral
(A) 52.4% (B) 68%
because _______.
(C) 74% (D) 80%
(A) it is formed by six spheres
(B) it is tetrahedral in shape 33. The space occupied by b.c.c. arrangement is
(C) it is formed by four spheres and the approximately _______.
centres form a regular tetrahedron (A) 50% (B) 68%
(D) it is formed by three spheres (C) 74% (D) 56%

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34. The maximum percentage of available volume 43. In the unit cell of NaCl lattice, there are
that can be filled in a face centered cubic _______.
system by an atom is _______. (A) 3 Na+ ions (B) 6 Na+ ions

(A) 74% (B) 68% (C) 6 Cl– ions (D) 4 NaCl units

(C) 34% (D) 26%
1.7 Defects in crystal structure

1.6 Packing in voids of ionic solids
44. Schottky defect is shown by _______.
35. If the radius ratio of cation to anion is in the (A) strongly ionic compounds
range of 0.225 – 0.414, then the coordination (B) compounds having high coordination
number of cation will be _______. number
(A) 2 (B) 4 (C) compounds containing cations and
(C) 6 (D) 8 anions of almost similar size

(D) all of these
36. If the type of the hole occupied is tetrahedral,

the radius ratio (r+ /r ) should be _______. 45. Schottky defect is noticed in _______.
¯
(A) 0.414  0.732 (A) NaCl (B) KCl
(B) > 0.732 (C) CsCl (D) All of these

(C) 0.155  0.225
46. The given structure represents _______.
(D) 0.225  0.414

37. For cubic coordination, the value of radius
ratio is _______.
Cation
(A) 0.732 – 1.000 (B) 0.225 – 0.414 Anion
(C) 0.000 – 0.225 (D) 0.414 – 0.732

38. In NaCl lattice, the radius ratio is

r
(A) Schottky defect
+
Na
= _______.
(B) Frenkel defect
r
Cl (C) Metal excess defect
(A) 0.225 (B) 0.115 (D) Metal deficiency defect

(C) 0.5248 (D) 0.471
47. Which of the following defect, if present,
39. For some crystals, the radius ratio for cation lowers the density of the crystal?
and anion is 0.525. Its coordination number (A) Frenkel
will be _______. (B) Schottky
(A) 2 (B) 4 (C) Substitution impurity defect
(C) 6 (D) 8 (D) Interstitial impurity defect

40. TiCl has structure similar to CsCl, the 48. Both Schottky and Frenkel defects are present
coordination number of Ti+ is _______. in _______.
(A) 4 (B) 6 (A) AgCl (B) AgBr
(C) 10 (D) 8 (C) AgI (D) ZnS

41. For an ionic crystal of the type AB, the value 1.8 Electrical properties
of (limiting) radius ratio is 0.40. The value
suggests that the crystal structure should be 49. The variation property of ability to conduct
_______. electricity of metals, non-metals and
(A) octahedral semiconductors is explained by _______.
(B) tetrahedral (A) energy gain enthalpy
(C) square planar (B) band theory
(D) planar triangular (C) bond theory

(D) hydride gap
42. Which of the following ions has the largest
radius? 50 . Silicon is a __ _____.
(A) Na+ (B) Mg2+ (A) conductor (B) semiconductor
(C) Al3+ (D) Si4+ (C) non-conductor (D) metal complex

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51. Germanium is an example of _______. 59. Each unit cell of NaCl consists of 4 chloride
(A) an intrinsic semiconductor ions and _______.
(A) 13 Na atoms (B) 4 Na+ ions
(B) a n-type semiconductor
(C) 6 Na atoms (D) 8 Na atoms
(C) a p-type semiconductor
(D) insulator r 
60. If the value of ionic radius ratio  c  is 0.52
52. A silicon solar battery makes use of _______. ra 
(A) n-type semiconductor in an ionic compound, the geometrical
arrangement of ions in crystal is _______.
(B) p-type semiconductor
(A) tetrahedral
(C) combination of Si doped with As and B
(B) planar triangular
(D) p-n junction
(C) octahedral

1.9 Magnetic properties (D) cubic

53. Which among the following is NOT a Carbon nanotubes (CNTs)
diamagnetic substance?
(A) water (B) sodium chloride
(C) oxygen (D) benzene

Miscellaneous

54. Which among the following is called a pseudo

solid?

(A) CaF (B) Glass
2
(C) NaCl (D) All of these

55. A solid X melts slightly above 273 K and is a
poor conductor of heat and electricity. To
which of the following categories does it
belong?

(A) Ionic solid

(B) Covalent solid

(C) Metallic

(D) Molecular

56. Value of heat of fusion of NaCl is _______.
(A) very low (B) very high
(C) moderate (D) zero
Carbon nanotubes (CNTs) are allotropes of carbon

57. Amorphous solids are _______. and are the members of the fullerene structural

family. CNTs have long, hollow and cylindrical
(A) solid substances
nanostructure with the walls formed by graphene
(B) liquids
(one-atom-thick sheets of carbon). These sheets are
(C) super cooled liquids rolled at specific and discrete angles, and the

combination of the rolling angle and radius decides
(D) substances with definite melting point

the nanotube properties. The unique strength of
58. The most malleable metals (Cu, Ag, Au) have CNTs is due to sp2 bonding present in them. CNTs
find applications in nanotechnology, electronics,
close - packing of the type _______.
optics and other fields of materials science and

(A) AAAA technology. These are not necessarily products of
(B) ABCABC high-tech laboratories but have been found in soot
from air, flames produced by burning methane,
(C) ABAB
ethylene and benzene, etc.
(D) ABCCBA

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