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CHEMISTRY
CLASS–XII
(THEORY)
Total Periods (Theory 160 + Practical 60)
Time: 3 Hours 70 Marks
Units No. Title No. of Periods Marks
Unit I Solid State 10
Unit II Solutions 10
Unit III Electrochemistry 12 23
Unit IV Chemical Kinetics 10
Unit V Surface Chemistry 08
Unit VI General Principles and Processes of Isolation of Elements 08
Unit VII p-Block Elements 12 19
Unit VIII d-and f-Block Elements 12
Unit IX Coordination Compounds 12
Unit X Haloalkanes and Haloarenes 10
Unit XI Alcohols, Phenols and Ethers 10
Unit XII Aldehydes, Ketones and Carboxylic Acids 10
Unit XIII Organic Compounds containing Nitrogen 10 28
Unit XIV Biomolecules 12
Unit XV Polymers 08
Unit XVI Chemistry in Everyday Life 06
Total 160 70
SYLLABUS
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Unit 1: Solid State (10 Periods)
Classificationofsolidsbasedondifferentbindingforces:molecular, ionic,covalentandmetallicsolids,amorphousand crystalline solids (elementary idea). Unit cell in two dimensional and three dimensional lattices, calculation of densityofunitcell,packinginsolids,packingefficiency,voids,numberofatomsperunitcellinacubicunitcell,pointdefects, electrical and magnetic properties.
Band theory of metals, conductors, semiconductors and insulators and n and p type semiconductors.
Unit II: Solutions (10 Periods) Types of solutions, expression of concentration of solutions of solids in liquids, solubility of gases in liquids, solid
solutions, colligative properties - relative lowering of vapour pressure, Raoult's law, elevation of boiling point, depression of freezing point, osmotic pressure, determination of molecular masses using colligative properties, abnormal molecular mass, Vanl Hoff factor.
Unit III: Electrochemistry (12 Periods) Redoxreactions,conductanceinelectrolyticsolutions,specificandmolarconductivity,variationsofconductivitywith
concentration, Kohtrausch’s Law, electrolysis and law of electrolysis (elementary idea), dry cell-electrolytic cells and Galvanic cells, lead accumulator, EMF of a cell, standard electrode potential, Nernst equation and its application to chemical cells, Relation between Gibbs energy change and EMF of a cell, fuel cells, corrosion.
Unit IV: Chemical Kinetics (10 Periods) Rate of a reaction (Average and instantaneous), factors affecting rate of reaction: concentration, temperature, catalyst;
orderandmolecularityofareaction,ratelawandspecificrateconstant,integratedrateequationsandhalflife(onlyforzeroandfirstorderreactions),conceptofcollisiontheory(elementaryidea,nomathematicaltreatment).Activationenergy, Arrhenious equation.
Unit V: Surface Chemistry (08 Periods) Adsorption - physisorption and chemisorption, factors affecting adsorption of gases on solids, catalysis, homogenous
and heterogenous activity and selectivity; enzyme catalysis colloidal state distinction between true solutions, colloids and suspension; lyophilic, lyophobic multi-molecular and macromolecular colloids; properties of colloids; Tyndall effect, Brownian movement, electrophoresis, coagulation, emulsion - types of emulsions.
Unit VI: General Principles and Processes of Isolation of Elements (08 Periods) Principlesandmethodsofextraction-concentration,oxidation,reduction-electrolyticmethodandrefining;occurrence
and principles of extraction of aluminium, copper, zinc and iron.
Unit VII: p-Block Elements (12 Periods) Group 15 Elements:Generalintroduction,electronicconfiguration,occurrence,oxidationstates,trendsinphysicaland
chemical properties; Nitrogen, preparation properties and uses; compounds of Nitrogen, preparation and properties of Ammonia and Nitric Acid, Oxides of Nitrogen(Structure only) ; Phosphorus - allotropic forms, compounds of Phosphorus: Preparation and Properties of Phosphine, Halides and Oxoacids (elementary idea only).
Group 16 Elements: Generalintroduction,electronicconfiguration,oxidationstates,occurrence,trendsinphysicalandchemicalproperties,dioxygen:Preparation,Propertiesanduses,classificationofOxides,Ozone,Sulphur-allotropicforms; compounds of Sulphur: Preparation Properties and uses of Sulphur-dioxide, Sulphuric Acid: industrial process of manufacture, properties and uses; Oxoacids of Sulphur (Structures only).
Group 17 Elements: General introduction, electronic configuration, oxidation states, occurrence, trends in physicaland chemical properties; compounds of halogens, Preparation, properties and uses of Chlorine and Hydrochloric acid, interhalogen compounds, Oxoacids of halogens (structures only).
Group 18 Elements: General introduction, electronic configuration, occurrence, trends in physical and chemicalproperties, uses.
Unit VIII: d-and f-Block Elements (12 Periods) Generalintroduction,electronicconfiguration,occurrenceandcharacteristicsoftransitionmetals,generaltrendsinproperties
ofthefirstrowtransitionmetals-metalliccharacter,ionizationenthalpy,oxidationstates,ionicradii,colour,catalyticproperty,magnetic properties, interstitial compounds, alloy formation, preparation and properties of K2Cr2O7, and KMnO4.
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Lanthanoids: Electronic configuration, oxidation states, chemical reactivity and lanthanoid contraction and itsconsequences.
Actinoids:Electronicconfiguration,oxidationstatesandcomparisonwithlanthanoids.
Unit IX: Coordination Compounds (12 Periods) Coordination compounds: Introduction, ligands, coordination number, colour, magnetic properties and shapes, IUPAC
nomenclature of mononuclear coordination compounds. Bonding, Werner’s theory, VBT, and CFT; structure and stereoisomerism, importance of coordination compounds (in qualitative analysis, extraction of metals and biological system).
Unit X: Haloalkanes and Haloarenes (10 Periods) Haloalkanes: Nomenclature, nature of C-X bond, physical and chemical properties, mechanism of substitution reactions,
optical rotation. Haloarenes: NatureofC-Xbond,substitutionreactions(Directiveinfluenceofhalogeninmonosubstitutedcompounds
only). Uses and environmental effects of - dichloromethane, trichloromethane, tetrachloromethane, iodoform, freons, DDT.
Unit XI: Alcohols, Phenols and Ethers (10 Periods) Alcohols: Nomenclature, methods of preparation, physical and chemical properties (of primary alcohols only),
identificationofprimary,secondaryandtertiaryalcohols,mechanismofdehydration,useswithspecialreferencetomethanol and ethanol.
Phenols: Nomenclature,. methods of preparation, physical and chemical properties, acidic nature of phenol, electrophillic substitution reactions, uses of phenols.
Ethers: Nomenclature, methods of preparation, physical and chemical properties, uses.
Unit XII: Aldehydes, Ketones and Carboxylic Acids (10 Periods) Aldehydes and Ketones: Nomenclature, nature of carbonyl group, methods of preparation, physical and chemical
properties, mechanism of nucleophilic addition, reactivity of alpha hydrogen in aldehydes: uses. Carboxylic Acids: Nomenclature, acidic nature, methods of preparation, physical and chemical properties uses.
Unit XIII: Organic compounds containing Nitrogen (10 Periods) Amines: Nomenclature, classification, structure, methods of preparation, physical and chemical properties, uses,
identificationofprimary,secondaryandtertiaryamines.
Cyanides and Isocyanides: will be mentioned at relevant places in text.
Diazonium salts: Preparation, chemical reactions and importance in synthetic organic chemistry.
Unit XIV: Biomolecules (12 Periods) Carbohydrates: Classification (aldoses and ketoses), monosaccahrides (glucose and fructose), D-L configuration
oligosaccharides (sucrose, lactose, maltose), polysaccharides (starch, cellulose, glycogen); Importance of carbohydrates. Proteins: Elementary idea of - amino acids, peptide bond, polypeptides, proteins, structure of proteins - primary,
secondary, tertiary structure and quaternary structures (qualitative idea only), denaturation of proteins; enzymes. Hormones - Elementary idea excluding structure.
Vitamins:Classificationandfunctions. Nucleic Acids: DNA and RNA.
Unit XV: Polymers (08 Periods) Classification: natural and synthetic, methods of polymerization (addition and condensation), copolymerization, some
important polymers: natural and synthetic like polythene, nylon polyesters, bakelite, rubber. Biodegradable and non-biodegradable polymers.
Unit XVI: Chemistry in Everyday life (06 Periods) Chemicals in medicines: analgesics, tranquilizers antiseptics, disinfectants, antimicrobials, antifertility drugs, antibiotics,
antacids, antihistamines. Chemicals in food:preservatives,artificialsweeteningagents,elementaryideaofantioxtdants. Cleansing agents: soaps and detergents, cleansing action.
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QUESTIONS PAPER DESIGNS
CLASS-XII
CHEMISTRY (CODE NO. 043) Time-3 Hours Marks-70
S.
No.
Typology of Questions Very
Short
Answer
(VSA)
(1 Mark)
Short
Answer -I
(SA-I)
(2 Marks)
Short
Answer -II
(SA-II)
(3 Marks)
Value
Based
Question
(4 Marks)
Long
Answer (LA)
(5 Marks)
Total
Marks
%
Weightage
1. Remembering—Knowledge based Simple recall questions, to know specific facts, terms, concepts, principles, or theories; Identify, define, or recite, information)
2 1 1 – – 7 10%
2. Understanding Comprehension—to be familiar with meaning and to understand conceptually, interpret, compare, contrast, explain, paraphrase, information).
– 2 4 – 1 21 30%
3. Application (Use abstract information in concrete situation, to apply knowledge to new situations, Use given content to interpret a situation, provide an example, or solve a problem)
– 2 4 – 1 21 30%
4. High Order Thinking Skills (Analysis & Synthesis—Classify, compare, contrast, or differentiate between different pieces of information; Organize and/or integrate unique pieces of information from a variety of sources)
2 – 1 – 1 10 14%
5. Evaluation—(Appraise, judge, and/or justify the value or worth of a decision or outcome, or to predict outcomes based on values)
1 – 2 1 – 11 16%
TOTAL 5×1=5 5×2=10 12×3=36 1×4=4 3×5=15 70(26) 100%
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QUESTION WISE BREAK UP
Type of Question Mark per Question Total No. of Questions Total Marks
VSA 1 5 05
SA-I 2 5 10
SA-II 3 12 36
VBQ 4 1 04
LA 5 3 15
Total 26 70
1. Internal Choice: There is no overall choice in the paper. However, there is an internal choice in one question of 2 marks weightage, one question of 3 marks weightage and all the three questions of 5 marks weightage.
2. The above template is only a sample. Suitable internal variations may be made for generating similar templates keeping the overall weightage to different form of questions and typology of questions same.
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C K
C K
Super Refresher
Every chapter divided into Sub-topics
All chapters as per Syllabus and NCERT Textbooks
CBSE
NCERT TextbookQuestions
with answers
NCERT ExamplesSolved
Additional Important & Boards’ Questions with answers
NCERT Exemplar Problems with answers
C K
Chemistry
C K
Variety of Value Based Questions
Model
Question Papers for Practice
HOTS questions with answersin every chapter
CONTENTS
1 The Solid State 1 – 35
2 Solutions 36 – 82
3 Electrochemistry 83 – 122
4 Chemical Kinetics 123 – 161
5 Surface Chemistry 162 – 191
6 General Principles and Processes of Isolation of Elements 192 – 213
7 p-Block Elements 214 – 260
8 d-and f-Block Elements 261 – 294
9 Coordination Compounds 295 – 341
10 Haloalkanes and Haloarenes 342 – 397
11 Alcohols, Phenols and Ethers 398 – 463
12 Aldehydes, Ketones and Carboxylic Acids 464 – 539
13 Organic Compounds containing Nitrogen 540 – 593
14 Biomolecules 594 – 629
15 Polymers 630 – 656
16 Chemistry in Everyday Life 657 – 678
Model Question Papers for Practice 679 – 693
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BASICS & BASIS
The Solid State11.1 Classification of Solids1.2 Crystal Lattice and Unit Cells1.3 Close Packed Structures1.4 Imperfections in Solids1.5 Electrical and Magnetic Properties of Solids
CONCEPTS
Isotropy and AnisotropyThe substances which have physical properties, such as electrical resistance or refractive index, same in all directions are called isotropic while those which have different physical properties in different directions are called anisotropic. The crystalline substances are anisotropic because of different arrangement of particles in different directions. On the other hand, amorphous solids are isotropic in nature because of irregular arrangement along all the directions.
Classification of Crystalline Solids on the Basis of Nature of Intermolecular Forces
The crystalline solids may be classified as :1. Molecular solids in which the constituent
particles are molecules, which are held together by dispersion forces, London forces, dipole-dipole forces or hydrogen bonds. These are further sub-divided as :
(i) Non-polar molecular solids. They consist of either atoms of noble gases or non-polar molecules. For example, helium, argon, H2, Cl2, Br2, I2 etc. molecules are held together by weak dispersion forces or London forces.
(ii) Polar molecular solids. They consist of molecules which have polar covalent bonds (like HCl, SO2, etc.) held together by relatively stronger dipole-dipole interactions.
(iii) Hydrogen bonded molecular solids. They consist of molecules containing polar covalent bonds between H and F, O or N
1.1 Classification of SolidsSolids are the substances which have definite
shape and definite volume. In terms of kinetic molecular model, solids have regular order of their constituent particles (atoms, molecules or ions).
The solids are broadly classified as crystalline and amorphous solids.
Crystalline solids are substances whose constituent particles (atoms, ions or molecules) are arranged in a definite arrangement or pattern e.g., sodium chloride, potassium nitrate, zinc sulphide, quartz etc.
Amorphous solids are substances whose constituent particles are not arranged in any regular arrangement or pattern e.g., amorphous solids are glass, rubber, plastics etc.
Characteristics of Crystalline and Amorphous Solids
Crystalline substances have regular geometry, sharp melting point, definite heat of fusion and can be cleaved along definite planes. When cut with a sharp edged tool, they split into two pieces and the newly formed surfaces are plain and smooth.
Amorphous substances donot have sharp melting point, no definite heat of fusion and when cut with a sharp edged tool, they undergo irregular breakage and split into two pieces with irregular surfaces.
CBSE_SUP_R_CHEM_G12_C01.indd 1 9/2/2016 5:05:50 PM
The Solid StateMBD Super Refresher Chemistry - XII2 3
atoms. Therefore, they are held together by hydrogen bonds. e.g., solid CO2, ice, argon, solid H2, HCl, etc.
2. Ionic solids in which the constituent particles are positively and negatively charged ions arranged in a regular fashion. These ions are held together by strong electrostatic forces. e.g., salts of NaCl, KNO3, ZnS, etc.
3. Metallic solids in which the constituent particles are positive ions (called kernels) immersed in a sea of mobile electrons held together by metallic bonding i.e., electric attraction between +ve ions and electrons. e.g., Cu, Ag, Fe, Mg, metals, etc.
4. Covalent or network solids in which the constituent particles are atoms which are held together by continuous system of covalent bonds. e.g., diamond, carborundum, boron nitride, etc.
TEST YOUR UNDERSTANDING
1 Which of the following solids are crystalline?
Fibre glass, naphthalene, potassium chloride, polyvinyl chloride, teflon, zinc sulphide.
Ans. Naphthalene, potassium chloride, zinc sulphide. 2 Which of the following is a molecular solid? Graphite, brass, solid CO2, LiBrAns. Solid CO2. 3 What are isotropic substances? Are
crystalline substances isotropic?Ans. The substances which have physical properties
such as refractive index, thermal expansion, electrical conductivities, etc., same in all directions are called isotropic substances.
The crystalline substances are not isotropic. 4 Solid A is very hard electrical insulator
in solid as well as in molten state and
melts at extremely high temperature. What type of solid is it?
Ans. Covalent or network solid like SiO2 (quartz) or SiC.
5 Which network solid is an exceptionally good conductor of electricity?
Ans. Graphite. 6 Pick out the odd ones from the following? Solid CO2, diamond, quartz, AlNAns. Solid CO2 because it is molecular solid while
all others are covalent or network solids. 7 Crystalline substances are isotropic?
True or False?Ans. False. 8 .............. solids are good conductors of
electricity. Complete the statement.Ans. Metallic.
1.2 Crystal Lattice and Unit CellsThe regular three dimensional arrangement of
particles (atoms, ions or molecules) of the crystal is called crystal lattice.
Lattice sites. The positions which are occupied by atoms, ions or molecules in the crystal are called lattice sites.
There are only 14 possible three dimensional lattices. These are called Bravais lattices.
Unit cell. The smallest repeating unit in space lattice which when repeated over and over again results in the crystal of the given substance is called unit cell.
Characteristics of a Unit CellA unit cell is characterized by three edges a, b, c
and angles a, b and g between the pair of edges. For example, angle a is between the edges b and c, angle b between the edges c and a and angle g between the edges a and b. Thus, a unit cell is characterized by six parameters a, b, c, a, b and g.
Types of Unit Cells Unit cells can be broadly divided into two types;
primitive and centred unit cells.(i) Primitive unit cells which have points (or
particles) only at the corners. These are also called simple unit cells.
(ii) Centred unit cells which have points (or particles) at the corners as well as at some other positions.
Centred unit cells are of three types : (a) Face centred unit cells in which the points
are present at the corners as well as at the centre of each face.
(b) Body centred unit cells in which the points are present at all the corners as well as at the body centre of the unit cell.
(c) End centred unit cells in which the points are present at all the corners and at the centre of any two opposite faces.
In all, there are seven types of primitive unit cells differing in a, b, c and a, b and g as given ahead:
CBSE_SUP_R_CHEM_G12_C01.indd 2 9/2/2016 5:05:50 PM
The Solid StateMBD Super Refresher Chemistry - XII2 3
System PossibleVariations
Axial distances Axial angles Examples
Cubic PrimitiveBody-centred Face-centred
a = b = c a = b = g = 90° NaCl, KCl, Zinc blende, Cu, Ag
Tetragonal PrimitiveBody-centred
a = b ≠ c a = b = g = 90° White tin, SnO2, TiO2, CaSO4
Orthorhombic PrimitiveBody-centredFace-centredEnd-centred
a ≠ b ≠ c a = b = g = 90° Rhombic sulphur, KNO3, PbCO3, BaSO4
Monoclinic PrimitiveEnd-centred
a ≠ b ≠ c a = g = 90°, b ≠ 90° Monoclinic sulphur, PbCrO2, Na2SO4.10H2O
Hexagonal Primitive a = b ≠ c a = b = 90°, g = 120° Graphite, ZnO, CdS.
Rhombohedral Primitive a = b = c a = b = g ≠ 90° Calcite (CaCO3), cinnabar (HgS), quartz, Sb
Triclinic Primitive a ≠ b ≠ c a ≠ b ≠ g ≠ 90° CuSO4.5H2O, K2Cr2O7, H3BO3.
There are seven crystal systems and fourteen Bravais lattices.
Number of Atoms in a unit cellNumber of atoms per unit cell are : Simple cubic = 1 atom Body centred cubic = 2 atoms Face centred cubic = 4 atoms
l Relationship between nearest neighbour distance (d) and radius (r) of an atom and edge length (a)
Simple cubic d = a r = a/2
Face centred cubic d = a2
r = a
2 2
Body centred cubic d = 3
2a r =
34
a
TEST YOUR UNDERSTANDING
1 Give the significance of lattice point.Ans. Lattice point represents the position of one
constituent particle (atom, molecule or ion) of the solid.
2 What is a primitive cell ?Ans. A primitive cell has particles (atoms) at all the
corners of the unit cell. 3 Name the crystal system in which all the
three axes are of equal length which are inclined at the same angle but the angle is not equal to 90°.
Ans. Rhombohedral. 4 Name the (i) most symmetrical and
(ii) most unsymmetrical crystal system.Ans. (i) Most symmetrical crystal system : Cubic (ii) Most unsymmetrical crystal system :
Triclinic. 5 How are unit cell and space lattice related ?Ans. Space lattice is obtained by repeating the
unit cell in three dimensions. The spatial arrangement, stoichiometry and density of unit cell and space lattice are equivalent.
6 For a body centred cubic arrangement, if a is the edge of unit cell, then radius of atom is related to ‘a’ as ......
Ans. 34
a
7 The unit cell edge length of CsBr, which has CsCl structure is 400 pm. Calculate the interionic distance in a crystal of CsBr.
Ans. For CsBr having CsCl structure,
Interionic distance = 3
2× edge length
= 32
× 400 = 346 4 pm. .
8 The total number of atoms per unit cell in a body centred cubic structure is .......... and in a face centred cubic structure is .............
Ans. 2, 4.
CBSE_SUP_R_CHEM_G12_C01.indd 3 9/2/2016 5:05:51 PM
The Solid StateMBD Super Refresher Chemistry - XII4 5
9 A simple cubic structure has eight atoms per unit cell. True or False.
Ans. False. It has 1 atom per unit cell.
10 A crystal system having the dimensions; a = b ≠ c, a = b = g = 90° is .........
Ans. Tetragonal.
1.3 Close Packed StructuresIn the formation of crystals, the constituent
particles get closely packed leaving minimum vacant space. This arrangement in which maximum available space is occupied is called close packed arrangement.
The number of nearest neighbours of a sphere is called its coordination number.
When we build the layers of atoms and represent the layers as A, B, C, …, etc., the arrangements may be expressed as : l AAA… type called simple cubic packing. l ABABA… type called hexagonal close
packing abbreviated as hcp. l ABCABCA… type called cubic close packing,
abbreviated as ccp or face centred cubic packing, abbreviated as fcc.
Tetrahedral and octahedral voids or sitesIn the close packing of spheres, certain hollows or
voids are left vacant and these are called interstitial voids or interstitial sites. Two important interstitial voids are : (i) Tetrahedral and (ii) octahedral voids.
It may be noted that in close packed arrange-ment (ccp or hcp), there are twice as many tetrahedral voids as there are spheres and there are same number of octahedral voids as the number of spheres.
Packing Efficiency in hcp and ccp StructuresPacking efficiency is the percentage of total
space filled by the particles. It can be easily shown that the packing efficiency
for different types of structures are :Hexagonal close packed (hcp) structure = 74%Cubic close packed (ccp) structure = 74%Body centred cubic packed (bcc) structure = 68%Simple cubic structure = 52.4%
Calculations Involving Unit Cell DimensionsFrom the unit cell dimensions, we can calculate
the volume of the unit cell. Knowing the mass of atoms in a unit cell, we can calculate the density of the unit cell as :
or Density, d = ZMNAa3
where a is edge length of unit cell, Z is the number of atoms in a unit cell, M is molar mass and NA is Avogadro number.
TEST YOUR UNDERSTANDING
1 What is the two dimensional coordination number of a molecule in a square close packed layer ?
Ans. 4. 2 What is the coordination number in hcp
and ccp ?Ans. 12 in both hcp and ccp. 3 Arrange simple cubic, body centred
cubic, face centred cubic and hexagonal close packing in the increasing order of packing efficiency.
Ans. Simple cubic < body centred cubic < face centred cubic = hexagonal close packing.
4 What is the coordination number of an ion occupying
(i) tetrahedral hole (ii) octahedral hole ? Ans. The coordination number of an ion occupying (i) tetrahedral hole = 4 (ii) octahedral hole = 6
5 In close packing of N spheres, how many (i) octahedral and (ii) tetrahedral sites are present ?
Ans. (i) Octahedral sites = N (ii) Tetrahedral sites = 2N 6 Which of the two spheres one occupying
a tetrahedral site and the other one occupying octahedral site is larger in size ?
Ans. The sphere occupying an octahedral site is larger in size than the sphere occupying tetrahedral site.
7 How many atoms are present per unit cell in a hcp structure ?
Ans. 6 8 An element ‘Z’ having bcc geometry
has atomic mass 60.22 u. Calculate the density of the unit cell, if its edge length is 200 pm.
CBSE_SUP_R_CHEM_G12_C01.indd 4 9/2/2016 5:05:51 PM
MBD CBSE Super Refresher ChemistryFor Class 12
Publisher : MBD GroupPublishers
Author : Dr Jauhar
Type the URL : http://www.kopykitab.com/product/10011
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