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Anuj Kapoor

Chemistry

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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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