ISC Class 11 Chemistry Syllabus 2025-26: Download FREE PDF

Paper I- Theory (3 Hours)

70 Marks 

Practical Work (3 Hours)

• Project Work 

• Practical File  

15 Marks

• 10 Marks

• 5 Marks

S. No.

UNIT

TOTAL WEIGHTAGE 

1

Some Basic Concepts of Chemistry

Physical Chemistry 

41 Marks

2

Structure of an Atom

3

Classification of Elements and Periodicity in Properties

4

Chemical Bonding and Molecular Structure

5

Chemical Thermodynamics

6

Equilibrium

7

Redox Reactions

Inorganic Chemistry 

6 Marks

8

Organic Chemistry: Some Basic Principles and Techniques

Organic Chemistry 

23 Marks

9

Hydrocarbons

TOTAL

70 Marks

1. Some Basic Concepts of Chemistry

General introduction: Importance and scope of chemistry. Study of matter. Understanding the laws of chemical combination. Dalton's atomic theory: concept of elements, atoms and molecules. Isotopic (atomic) and molecular masses, mole concept and molar mass, percentage composition, empirical and molecular formula. Stoichiometry and calculations based on chemical reactions.

2. Structure of an Atom

Discovery of fundamental particles electron, proton and neutron), atomic number, isotopes and isobars. Thomson's model and its limitations. Rutherford's experimental model and its limitations. Dual nature of matter and light. Bohr's atomic model and its limitations (de Broglie's equation, Heisenberg’s uncertainty principle), concept of shells, subshells, 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 of maximum multiplicity. Electronic configuration of atoms, stability of half-filled and filled orbitals.

3. Classification of Elements and Periodicity in Properties

Significance of classification; study of Mendeleev’s periodic law and its limitations; Modern Periodic Law and the present form of periodic table leading to periodic trends in properties of elements - atomic radii, ionic radii, valency, ionisation enthalpy, electron gain enthalpy, electronegativity. Nomenclature of elements with atomic numbers greater than 100.

4. Chemical Bonding and Molecular Structure

Valence electrons, ionic bond character, covalent bond of ionic bond, covalent bond, bond parameters, Lewis structure, polar character of covalent bond, VSEPR theory, geometry of covalent molecules, valence bond theory, concept of hybridisation involving s, p and d orbitals and shapes of some simple molecules. Coordinate bond. Molecular orbital theory of homonuclear diatomic molecules (qualitative idea only). Resonance and hydrogen bond. 

5. Chemical Thermodynamics

(i) Introduction, concepts, types of system, surroundings, extensive, intensive properties and state functions.

(ii) First Law of Thermodynamics and its significance, work, heat, internal energy, enthalpy (∆U or ∆E and ∆H), heat capacity and specific heat. Hess's law of constant heat summation, enthalpy of bond dissociation, combustion, formation, atomisation, sublimation, phase transition, ionisation, solution and dilution. 

(iii) Second Law of Thermodynamics and its significance, spontaneity of a chemical change; Entropy, Free Energy. Inadequacy of First Law and need for Second Law; Ideas about reversible (recapitulation), spontaneous and non-spontaneous processes

(iv)Third Law of Thermodynamics – statement only.

6. Equilibrium

(i) Chemical Equilibrium. 

Introduction of physical and chemical equilibrium and its characteristics. The dynamic nature of equilibrium, the law of mass action, the equilibrium constant and factors affecting equilibrium. Le Chatelier's principle and its applications.

(ii) Ionic equilibrium 

Introduction, electrolyte (strong and weak), non-electrolyte, ionisation, degree of ionisation of polybasic acids, acid strength, concept of pH, pH indicators, buffer solution, common ion effect (with illustrative examples). Henderson equation, hydrolysis

7. Redox Reactions

Concept of oxidation and reduction, redox reactions, oxidation number, change in oxidation number, balancing redox reactions (in terms of loss and gain of electrons). Applications of redox in various types of chemical reactions.

8. Organic Chemistry - Some Basic Principles and Techniques

General introduction, classification and IUPAC nomenclature of organic compounds and isomerism. Methods of purification, qualitative and quantitative analysis. Electron displacement in a covalent bond: inductive effect, electromeric effect, resonance and hyperconjugation. Homolytic and heterolytic bond fission of a covalent bond: free radicals, carbocations, carbanions, electrophiles and nucleophiles, types of organic reactions.

9. Hydrocarbons 

Classification of Hydrocarbons

I. Aliphatic Hydrocarbons

(i) Alkanes - Nomenclature, isomerism, conformation (methane and ethane), physical properties, chemical properties including free radical mechanism of halogenation, combustion and pyrolysis.

(ii) Alkenes - Nomenclature, structure of double bond (ethene), isomerism; methods of preparation; physical properties, chemical properties; addition of hydrogen, halogen, water, hydrogen halides (Markownikoff's addition and peroxide effect), ozonolysis, oxidation, mechanism of electrophilic addition.

(iii)Alkynes - Nomenclature, structure of triple bond (ethyne), methods of preparation; physical properties, chemical properties: acidic character of alkynes, addition reactions - hydrogen, halogens, hydrogen halides and water. 

II. Aromatic Hydrocarbons

Introduction, IUPAC nomenclature, benzene: resonance, aromaticity, chemical properties, mechanism of electrophilic substitution. Nitration, sulphonation, halogenation, Friedel-Crafts alkylation and acylation, directive influence of functional group in monosubstituted benzene. Carcinogenicity and toxicity.

Introduction/purpose

Contents

Analysis/ material aid (graph, data, structure, pie charts, histograms, diagrams, etc.)

Presentation

Bibliography

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