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Anuj Kapoor
Chemistry
11
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CHEMISTRY
CLASS–XI
Total Periods (Theory 160 + Practical 60)
Time: 3 Hours 70 Marks
Unit No. Title No. of Periods Marks
Unit I Some Basic Concepts of Chemistry 1211
Unit II Structure of Atom 14
Unit III Classifi cation of Elements and Periodicity in Properties 08 04
Unit IV Chemical Bonding and Molecular Structure 14
21Unit V States of Matter: Gases and Liquids 12
Unit VI Chemical Thermodynamics 16
Unit VII Equilibrium 14
Unit VIII Redox Reactions 06
16Unit IX Hydrogen 08
Unit X s-Block Elements 10
Unit XI Some p-Block Elements 14
Unit XII Organic Chemistry: Some Basic Principles and Technique 14
18Unit XIII Hydrocarbons 12
Unit XIV Environmental Chemistry 06
Total 160 70
Unit 1: Some Basic Concepts of Chemistry (Periods 12)
General Introduction: Importance and scope of chemistry. Nature of matter, laws of chemical combination, Dalton’s atomic theory: concept of elements, atoms and
molecules.
SYLLABUS
Atomic and molecular masses, mole concept and molar mass, percentage composition, empirical and molecular formula, chemical reactions, stoichiometry and calculations based on stoichiometry.
Unit II: Structure of Atom (Periods 14) Discovery of electron, proton and neutron, atomic number, isotopes and isobars. Thompson’s model and its limitations.
Rutherford’s model and its limitations, Bohr’s model and its limitations, concept of shells and subshells, dual nature of matter and light, de Broglie’s relationship, Heisenberg uncertainty principle, concept of orbitals, quantum numbers, shapes of s, p and d orbitals, rules for filling electrons in orbitals–Aufbau principle, Pauli’s exclusion principle and Hund’s rule, electronic configuration of atoms, stability of half filled and completely filled orbitals.
Unit III: Classification of Elements and Periodicity in Properties (Periods 08) Significance of classification, brief history of the development of periodic table, modern periodic law and the present
form of periodic table, periodic trends in properties of elements – atomic radii, ionic radii, inert gas radii, ionization enthalpy, electron gain enthalpy, electronegativity, valency. Nomenclature of elements with atomic number greater than 100.
Unit IV: Chemical Bonding and Molecular Structure (Periods 14) Valence electrons, ionic bond, covalent bond, bond parameters, Lewis structure, polar character of covalent bond,
covalent character of ionic bond, valence bond theory, resonance, geometry of covalent molecules, VSEPR theory, concept of hybridization, involving s, p and d orbitals and shapes of some simple molecules, molecular orbital theory of homonuclear diatomic molecules (qualitative idea only), hydrogen bond.
Unit V: States of Matter: Gases and Liquids (Periods 12) Three states of matter, intermolecular interactions, types of bonding, melting and boiling points, role of gas laws in
elucidating the concept of the molecule, Boyle’s law, Charle’s law, Gay Lussac’s law, Avogadro’s law, ideal behaviour, empirical derivation of gas equation, Avogadro’s number, ideal gas equation. Deviation from ideal behaviour, liquefaction of gases, critical temperature, kinetic energy and molecular speeds (elementary idea), Liquid State – vapour pressure, viscosity and surface tension (qualitative idea only, no mathematical derivations).
Unit VI: Chemical Thermodynamics (Periods 16) Concepts of system and types of systems, surroundings, work, heat, energy, extensive and intensive properties, state
functions. First law of thermodynamics – internal energy and enthalpy, heat capacity and specific heat, measurement of DU
and DH, Hess’s law of constant heat summation, enthalpy of bond dissociation, combustion, formation, atomization, sublimation, phase transition, ionization, solution and dilution. Second law of Thermodynamics (brief introduction).
Introduction of entropy as a state function, Gibb’s energy change for spontaneous and non-spontaneous processes, criteria for equilibrium.
Third law of thermodynamics (brief introduction).
Unit VII: Equilibrium (Periods 14) Equilibrium in physical and chemical processes, dynamic nature of equilibrium, law of mass action, equilibrium constant,
factors affecting equilibrium – Le Chatelier’s principle, ionic equilibrium – ionization of acids and bases, strong and weak electrolytes, degree of ionization, ionization of poly basic acids, acid strength, concept of pH, Henderson Equation, hydrolysis of salts (elementary idea), buffer solution, solubility product, common ion effect (with illustrative examples).
Unit VIII: Redox Reactions (Periods 06) Concept of oxidation and reduction, redox reactions, oxidation number, balancing redox reactions, in terms of loss and gain
of electrons and change in oxidation number, applications of redox reactions.
Unit IX: Hydrogen (Periods 08) Position of hydrogen in periodic table, occurrence, isotopes, preparation, properties and uses of hydrogen, hydrides–ionic,,
covalent and interstitial, physical and chemical properties of water, heavy water, hydrogen peroxide – preparation, reactions and structure and use, hydrogen as a fuel.
Unit X: s-Block Elements (Alkali and Alkaline Earth Metals) (10 Periods) Group 1 and Group 2 Elements: General introduction, electronic configuration, occurrence, anomalous properties of
the first element of each group, diagonal relationship, trends in the variation of properties (such as ionization enthalpy, atomic and ionic radii), trends in chemical reactivity with oxygen, water, hydrogen and halogens, uses.
Preparation and Properties of Some Important Compounds: Sodium Carbonate, Sodium Chloride, Sodium Hydroxide and Sodium Hydrogencarbonate, Biological importance of
sodium and potassium. Calcium Oxide and Calcium Carbonate and their industrial uses, biological importance of Magnesium and Calcium.
Unit XI: Some p-Block Elements (Periods 14) General Introduction to p-Block Elements Group 13 Elements: General introduction, electronic configuration, occurrence, variation of properties, oxidation
states, trends in chemical reactivity, anomalous properties of first element of the group, Boron – physical and chemical properties, some important compounds, Borax, Boric acid, Boron Hydrides, Aluminium: Reactions with acids and alkalies, uses.
Group 14 Elements: General introduction, electronic configuration, occurrence, variation of properties, oxidation states, trends in chemical reactivity, anomalous behaviour of first elements. Carbon-catenation, allotropic forms, physical and chemical properties; uses of some important compounds: oxides. Important compounds of silicon and a few uses: Silicon Tetrachloride, Silicones, Silicates and Zeolites, their uses.
Unit XII: Organic Chemistry – Some Basic Principles and Technique (Periods 14) General introduction, methods of purification, qualitative and quantitative analysis, classification and IUPAC nomenclature
of organic compounds. Electronic displacements in a covalent bond: inductive effect, electromeric effect, resonance and hyper conjugation. Homolytic and heterolytic fission of a covalent bond: free radicals, carbocations, carbanions, electrophiles and nucleophiles, types of organic reactions.
Unit XIII: Hydrocarbons (Periods 12) Classification of Hydrocarbons Aliphatic Hydrocarbons: Alkanes: Nomenclature, isomerism, conformation (ethane only), physical properties, chemical reactions including free
radical mechanism of halogenation, combustion and pyrolysis.
Alkenes: Nomenclature, structure of double bond (ethene), geometrical isomerism, physical properties, methods of preparation, chemical reactions: addition of hydrogen, halogen, water, hydrogen halides (Markownikov’s addition and peroxide effect), ozonolysis, oxidation, mechanism of electrophilic addition.
Alkynes: Nomenclature, structure of triple bond (ethyne), physical properties, methods of preparation, chemical reactions: acidic character of alkynes, addition reaction of–hydrogen, halogens, hydrogen halides and water.
Aromatic hydrocarbons : Introduction, IUPAC nomenclature, benzene: resonance, aromaticity, chemical properties: mechanism of electrophilic substitution, Nitration, sulphonation, halogenation, Friedel Craft’s alkylation and acylation, directive influence of functional group in monosubstituted benzene. Carcinogenicity and toxicity.
Unit XIV: Environmental Chemistry (Periods 06) Environmental pollution – air, water and soil pollution, chemical reactions in atmosphere, smog, major atmospheric
pollutants, acid rain, ozone and its reactions, effects of depletion of ozone layer, greenhouse effect and global warming – pollution due to industrial wastes, green chemistry as an alternative tool for reducing pollution, strategies for control of environmental pollution.
QUESTION PAPER DESIGN
CLASS-XI
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%
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.
Super Refresher
Every chapter divided
into Sub-topics
All chapters as per
Syllabus and NCERT Textbooks
CBSE
NCERT Textbook
Questions with answers
NCERT Exemplar
Problems
with answers
Additional Important
Questions
with answers
ChemistryVariety of
Value Based
Questions
Model
Test
Papers for
Practice
HOTS
questions with answers
in every chapter
CONTENTS
1 Some Basic Concepts of Chemistry 1 – 40
2 Structure of Atom 41 – 83
3 Classification of Elements and Periodicity in Properties 84 – 116
4 Chemical Bonding and Molecular Structure 117 – 171
5 States of Matter 172 – 202
6 Thermodynamics 203 – 239
7 Equilibrium 240 – 305
8 Redox Reactions 306 – 343
9 Hydrogen 344 – 376
10 s-Block Elements 377 – 406
11 Some p-Block Elements 407 – 435
12 Organic Chemistry (Some Basic Principles and Techniques) 436 – 486
13 Hydrocarbons 487 – 527
14 Environmental Chemistry 528 – 549
Model Question Papers for Practice 1 – 8
11 Some Basic Concepts of
Chemistry
CONCEPTS
1.1 Chemistry and its Importance
1.2 Units and Scientific notations
1.3 Matter and its Classification
1.4 Laws of Chemical Combination
1.5 Molecular formula and Mole Concept
1.6. Chemical stoichiometry and Solutions.
1
1.1 Chemistry and its Importance
� Chemistry may be defined as that branch of
science which deals with the study of atoms,
molecules and their transformations. Or It is that
branch of science which deals with the study of
composition, structure and properties of matter.
� Branches of Chemistry. The main branches
of chemistry are Physical chemistry, Organic
chemistry, Inorganic chemistry and
Analytical chemistry etc.
� Importance of Chemistry. Chemistry plays
an important role in meeting human needs for
food, health care products and other materials
aimed at improving the quality of life.
1. The medicines used to reduce tension are
called ............ .
Ans. Tranquilizers.
2. Name the important branches of
chemistry.
Ans. These are Physical chemistry, Inorganic
chemistry and Organic chemistry.
3. What is AZT ? Give its use.
Ans. AZT is Azidothymidine. It is used for AIDS
victims.
4. Name two chemical compounds which
are used in the treatment of cancer.
Ans. Cis-platin and taxol.
5. Name the compound which is generally
added for the sterilization of water.
Ans. Chlorine (0.2 to 0.4 ppm).
1.2 Units and Scientific Notations
� Physical quantities. Properties of matter
like mass, length, time and temperature etc.
are expressed in terms of their numerical
values with appropriate units are termed as
physical quantities.
� Fundamental or basic units. There are
seven physical quantities, which have
independent units which cannot be derived
from any other unit. These are known as
fundamental or basic units.
BASICS & BASIS
CHP-01.pmd 9/7/2016, 2:53 PM1
2 MBD Super Refresher Chemistry-XI
� S.I. System (Systems Internationale). Seven basic units in S.I. system are as follows :
Quantity Units Symbol
1. Length (l) metre m
2. Mass (m) kilogram kg
3. Time (t) second s
4. Temperature (T) kelvin K
5. Amount of substance (n) mole mol
6. Electric current (I) ampere A
7. Luminous intensity (I0) candela cd
� Derived units. The units of various physical quantities that could be derived from seven basic units
are known as derived units. Some common derived units have been tabulated as follows :
Some common derived units
Physical quantity Relation with other Units Symbol
basic quantities
Area (Length)2 m2 —
Volume (Length)3 m3 —
Density Mass per unit volume kg/m3 —
or kg m–3 —
Speed Distance travelled per unit time m/s or m s-1 —
Acceleration Speed change per unit time m/s × 1/s —
or m s–2 —
Force Mass × acceleration newton N (= kg m s–2)
Pressure Force per unit area pascal Pa (= kg m–1s–2)
Energy, work Force × distance travelled joule J (= kg m s–2 × m or kg m2 s–2)
Power Energy / Time watt W (= kg m2 s–3 or Js–1)
Electric charge Current × Time coulomb C (= As)
Potential difference — volt V (= kg m2 s–3 or J A–1 s–2
or JC–1)
Electric resistance Potential difference/current ohm Ω (= VA–1)
Electrical conductance1
Resistanceohm–1 or siemen S (= AV–1)
Frequency Cycles/sec hertz Hz (= s–1)
� Precision and accuracy. Closeness of values
among a set of measurements of a physical
quantity is known as precision while closeness
of single measurement of a value to its true
value is termed as accuracy.
� Scientific Notation. Very large or very
small numbers are generally expressed in
exponential form or scientific notations. In
scientific notations, a number is expressed as
N × 10n
‘N’ is called digit term and is a number
between 1.0 and 9.999 while ‘n’ is also a number
(a single or a multiple number) known as
exponent. For numbers greater than 9.999, ‘n’
has positive value, while for numbers less than
1, ‘n’ has a negative value.
� Significant figures. Significant figures are
the digits in a precisely recorded
measurement.
Significant figures in a number are all the
certain digits plus one doubtful digit at the
end of the number.
CHP-01.pmd 9/7/2016, 2:53 PM2
3Some Basic Concepts of Chemistry
1. What is the SI units of density ?
Ans. kgm–3
2. What is the atomicity of hydrogen ?
Ans. Two.
3. –273ºC = ............ K.
Ans. 0.
4. What is the SI units of molarity ?
Ans. mol dm–3.
5. How many basic units are present in
SI system ?
Ans. Seven.
1.3 Matter and its Classification
� Matter
Anything that has mass and occupies space and
can be felt by one or more of the known five senses
is known as matter. Classification of matter :
I. Physical Classification. Depending upon
the physical state, matter could be classified
into (a) solid state (b) l iquid state
(c) gaseous state.
II. Chemical Classification. Based upon its
composition, matter could be classified into
following three types : (1) elements
(2) compounds (3) mixtures.
1. Element. It is a pure substance which can
neither be built up from nor decomposed into
two or more still simpler substances by any
known physical or chemical methods. e.g.
carbon, iron, hydrogen, sulphur etc.
Elements may further be sub-divided into
(a) Metals e.g. Na, Mg, Al, Fe etc.
(b) Metalloids e.g. As, Sb etc.
(c) Non-metals e.g. O, N, S, P, Cl etc.
(d) Noble gases e.g. He, Ne, Ar, Kr etc.
2. Compound. It is a substance which can be
obtained by the combination of atoms of two
or more, same or different elements combined
together in a definite ratio by weight.
e.g., Cl2, SO
2, NaCl etc.
3. Mixture. A combination of two or more elements
or compounds in any proportion so that they
may not lose their identity is known as a
mixture. Mixtures are further of two types :
(a) Homogeneous mixtures. In this case the
composition of the mixture is the same throughout
the mixture and the constituents are
indistinguishable e.g. air, gasoline, alloys etc.
(b) Heterogeneous mixtures. In such mixtures
the composition is not the same throughout
the mixture and the components could be
easily separated e.g. a mixture of sand and
common salt, iron filings and sulphur.
1.4 Laws of Chemical Combination
1. The Law of Conservation of Mass. It statesthat total mass of the reactants is always equalto that of the products during any physical orchemical change.
OrMatter can neither be created nor destroyedby any known physical or chemical change.This law is also known as “The Law of
indestructibility of Matter”.
2. The Law of Definite Proportions Or Lawof constant composition. It states that apure chemical compound is always made upof the same elements combined together in thesame fixed ratio by mass.
3. The Law of Multiple Proportions. It statesthat when two elements combine to form twoor more compounds, the weights of one of theelements which combine with the fixed weightof the other element bear a simple wholenumber ratio to one another.
1. Why is air sometimes considered as a
heterogeneous mixture ?
Ans. This is due to the presence of dust particles
which donot mix with gas homogeneously.
2. Which of the following are compounds ?
Milk, 22 carat gold, Diamond, Ice.
Ans. Ice.
3. Give two examples of homogeneous
mixtures.
Ans. (i) Sodium chloride mixed with water
(ii) 22-carat gold.
4. What are the different states of water ?
Ans. These are solids, liquids and gases.
5. Give two examples of metalloids.
Ans. Arsenic, antimony.
CHP-01.pmd 9/7/2016, 2:53 PM3
4 MBD Super Refresher Chemistry-XI
4. Law of Reciprocal Proportions. It states
that when two elements combine separately
with the fixed weight of a third element, the
ratio of their weights is either the same or a
simple whole number multiple of the ratio in
which they also combine with each other.
5. Gay Lussac’s Law of Combining
Volumes. It states that whenever gases react
with each other they do so in a simple ratio by
volumes to each other as well as to products
formed in the gaseous state all volumes being
measured under similar conditions of
temperature and pressure.
� Dalton’s atomic theory
The basic postulates of the theory are :
(i) All matter is made up of extremely small
indivisible particles known as atoms.
(ii) Atoms of an element are identical in every
respect i.e. of mass, shape, size and
properties.
(iii) Atoms of different elements are different in
all respects from one another.
(iv) Atom is the smallest unit of matter that takes
part in chemical reactions.
(v) Atoms of same or different elements combine
together in a definite ratio by mass to form
compound atoms (later on termed as
molecules).
(vi) Atom can neither be created nor destroyed
by any physical or chemical methods.
Dalton’s atomic theory has been suitably modified
due to the discovery of isotopes and isobars,
sub-atomic particles like electrons, protons and
neutrons, destruction and subsequent conversion
of mass into energy, however the basic fabric of
the theory holds good even today.
� Modified atomic theory
(i) An atom is the smallest particle of matter
that takes part in a chemical reaction and
may or may not be capable of independent
existence.
(ii) A molecule is a smallest unit of matter,
capable of independent existence.
(iii) Under similar conditions of temperature
and pressure, equal volumes of all the gases
contain equal number of molecules.
Avogadro’s hypothesis has following
applications :
(i) To deduce the atomicity of elementary
gases.
(ii) To establish a relationship between the
vapour density and the molecular mass of
a gas or vapour.
(iii) To establish a relationship between the
molar mass and the molar volume.
1. Is law of constant composition true for
all types of compounds ?
Ans. No, it is not true when isotopes of elements
are involved.
2. What are isotopes ?
Ans. These are the atoms of same element having
same atomic number but different mass
numbers.
3. What is law of conservation of mass and
energy ?
Ans. It states that mass and energy are
interconvertible but sum of mass and energy
always remains constant.
4. Which law of combination is not
explained by Dalton’s atomic theory ?
Ans. Law of Gaseous volumes.
5. Which law of combination does not
involve masses ?
Ans. Law of Gaseous volumes.
1.5 Molecular Formula and Mole Concept
� Atomic mass unit (amu). It is 1/12th of the
mass of an atom of carbon (C12-isotope).
Atomic mass of an element is the average
relative mass of the atom of an element as
compared to the mass of an atom of carbon
(C12) taken as 12 amu. Today, amu has been
replaced by ‘u’ which is known as unified
mass.
� Molecular mass of a substance may also be
defined as :
The average relative mass of a molecule of a
substance as compared with the mass of an
atom of carbon (C12) taken as 12 amu. For
ionic substances, the term formula mass is
used instead of molecular mass since such
substances do not exist in the form of
molecules.
The molecular/formula mass of a molecular
species is the sum of the atomic masses of all
the atoms in a formula unit of the substance.
CHP-01.pmd 9/7/2016, 2:53 PM4
MBD CBSE Super Refresher ChemistryFor Class 11
Publisher : MBD GroupPublishers
Author : Anuj Kapoor
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