Chemistry Science (English Medium) Class 12 CBSE Syllabus 2025-26

• Classification of solids

1. Crystalline solids
2. Amorphous solids

• The distinction between Crystalline and Amorphous Solids
• Isomorphous solids and polymorphous solids

• Classification of crystalline solids

1. Molecular solids:
   a) Polar molecular solids
   b) Non-polar molecular solids
   c) Hydrogen-bonded molecular solids
2. Ionic Solids
3. Metallic solids
4. Covalent or Network Solids

• Structure and properties of diamond, graphite, and fullerene

• Unit cell
• Crystal lattice or space lattice
• Two-dimensional lattice and unit cell
• Three-dimensional lattice and unit cell

• Primitive Unit Cells
• Centred Unit Cells
  1) Body-Centred Unit Cells
  2) Face-Centred Unit Cells
  3) End-Centred Unit Cells
• Bravais lattices

• Primitive Cubic Unit Cell
• Body-Centred Cubic Unit Cell
• Face-Centred Cubic Unit Cell

• Packing in solids
• Close Packing in One Dimension
  1) Coordination number
• Close Packing in Two Dimensions
  1) Square close packing in two dimensions
  2) Hexagonal close packing of spheres in two dimensions
• Close Packing in Three Dimensions
• Three-dimensional close-packed structure

• Stage I - Linear packing in one dimension
• Stage II - Planar packing in two dimensions
  1) AAAA type, square close-packed structure
  2) ABAB type, hexagonal close-packed structure
• Stage III - Close packing in three dimensions
  1) AAAA type, simple cubic structure
  2) ABAB type, hexagonal close-packed structure
  3) ABCABC type, cubic close-packed structure

• Number of voids per atom in hcp and ccp structures
• Locating tetrahedral and octahedral voids: locating tetrahedral voids, Locating octahedral voids

• Calculation of density of unit cell

point defects and line defects

• Magnetic properties:

1. Magnetising field
2. Magnetic permeability
3. Intensity of magnetisation
4. Magnetic induction or total magnetic field
5. Magnetic susceptibility

• Substances can be classified into five categories:

1. Paramagnetic
2. Diamagnetic
3. Ferromagnetic
4. Antiferromagnetic
5. Ferrimagnetic

1. Gaseous Solutions
2. Liquid Solutions
3. Solid Solutions

• Mass percentage (w/w)
• Volume percentage (V/V)
• Mass by volume percentage (w/V)
• Parts per million
• Mole fraction
• Molarity
• Molality
• Standard solutions and working standards
• Advantages of using standard solutions

• Ideal Solutions
• Non-ideal Solutions

• Non-ideal solutions - positive deviation from Rauolt's Law
• Non-ideal solutions - negative deviation from Rauolt's Law

• Factors responsible for deviation from Raoult’s law

1. Solute-solvent interactions
2. Dissociation of solute
3. Association of solute
4. Temperature
5. Pressure
6. Concentration

• Abnormal molecular masses
  a) Association of solute particles
  b) Dissociation of solute particles
• Van't Hoff Factor
• Significance of van't Hoff factor
  a) Degree of dissociation
  b) Degree of association

• Electrochemical reactions
• Electrodes
• Types of electrochemical cells

1. Galvanic cell
2. Electrolytic cells

• Galvanic or Voltaic cells

• Reduction half-cell
• Oxidation half-cell
• Joining half-cells
• Anodic oxidation
• Cathodic reduction
• Completion of circuit
• Consumption of Electrodes

• Salt bridge
• Cell notation or representation of a galvanic cell
• Cell electromotive force (e.m.f.)

• Reference electrode
• Standard Hydrogen Electrode (SHE): Construction, Electrode reactions, Application, Limitations
• Calomel electrode: Construction, Electrode reactions, Advantages of calomel electrode

• Derivation of Nernst equation
• Applications of Nernst equation

• Conductors
• Difference between Electronic and Electrolytic conduction
• Non-electrolytes
• Factors affecting electronic or metallic conduction
• Factors affecting electrical conductivity of electrolytic solutions
• Electrolytic conduction (Conductance in electrolytic solutions)

• Electrolytic cells
• Process of electrolysis
• Preferential Discharge Theory
• Some Examples of Electrolysis
• Quantitative Aspects of Electrolysis
• Faraday's laws of electrolysis
  1) Faraday's First Law of Electrolysis
  2) Faraday's Second Law of Electrolysis

• Fuel cells
• Hydrogen-oxygen fuel cell
• Advantage and disadvantage of fuel cell

• Corrosion
• Experiment
• Rusting Process and Corrosion Effect

• Gibbs energy change and e.m.f. of a cell
• Standard cell potential and equilibrium constant

• Laws of Electromagnetic Induction or Faraday's Laws of Induction
  1) First law
  2) Second Law

• Various factors influencing the rate of a chemical reaction

1. Concentration of reactants
2. Pressure of gaseous reactants
3. Temperature of the system
4. Presence of a catalyst

• Dependence of Rate on Concentration, temperature, catalyst
• Rate Expression and Rate Constant/ Rate law and Specific Rate Constant
• Order of a Reaction
• Molecularity of a Reaction

• Integrated rate law for zero order reactions
• Units of rate constant of zero order reactions
• Graphical representation of zero order reaction
• Examples of zero order reactions

• Integrated rate law for first order reactions
• Units of rate constant for the first order reaction
• Graphical representation of first order reaction
• Examples of first order reactions
• Various forms of the integrated rate law for the first order reactions

• Half life of the first order reactions (`t _(1/2)`)
• Half life and rate constant of the first order reaction
• Graphical representation of Half life period of first order reaction
• Half life of zero order reactions

• Activation energy
• Arrhenius equation
• Most probable kinetic energy
• Effect of Catalyst

• Collision between reactant molecules
• Energy requirement - Activation energy
• Orientation of reactant molecules

• Occurrence and characteristics of transition metals

• Properties of the first-row transition metals – metallic character
• Atomic and ionic radii
• Metallic character
• Melting and boiling points
• Colour
• Physical Properties
• Variation in Atomic and Ionic Sizes of Transition Metals
• Ionisation Enthalpies
• Oxidation States
• Standard electrode potentials
• Trends in the M²⁺/M Standard Electrode Potentials
• Trends inthe M³⁺/M²⁺ Standard Electrode Potentials
• Trends in Stability of Higher Oxidation States
• Chemical Reactivity and E^θ Values
• Magnetic Properties
• Formation of Coloured Ions
• Formation of Complex Compounds
• Catalytic Properties
• Complex formation
• Formation of Interstitial Compounds
• Alloy Formation
• Oxides and oxoanions of transition metals

• Potassium dichromate K₂Cr₂O₇
• Potassium permanganate KMnO₄

• Types of adsorption

1. Physical adsorption (Physisorption or van der Waals' adsorption)
2. Chemical adsorption (Chemisorption or activated adsorption)

• Difference between physisorption and chemisorption

• Adsorption isotherm
• Freundlich adsorption isotherm
• Langmuir adsorption isotherm

• Important features of solid catalysts

1. Catalytic activity
2. Catalytic selectivity
3. Shape selective catalysis by zeolites

• Examples of colloids
• Classification of colloids
• Preparation of Colloids
• Purification of colloidal solution
• Properties of colloidal dispersions
• Methods to effect coagulation
• Emulsions
• Applications of colloids
• Dispersed phase and dispersion medium
• True solutions, colloids, and suspensions
• Types of colloidal systems

• Chemical methods
• Electrical disintegration or Bredig’s Arc method
• Peptization

• Dialysis
• Electro-dialysis
• Ultrafiltration

• Colligative properties
• Tyndall effect
• Colour
• Brownian movement
• Charge on colloidal particles
• Electrophoresis
• Coagulation of lyophilic sols
• Coagulation or precipitation
• Methods to effect coagulation
• Methods to prevent coagulation of colloids (Protection of colloids)

• Emulsion
• Types of emulsions
  1) Oil-in-water emulsion (O/W type)
  2) Water-in-oil emulsion (W/O type)
• Properties of emulsions
• Deemulsification

• Colloids in our daily life

1. Natural phenomena
   a) Blue colour of sky and sea
   b) Fog, mist, and rain
   c) Soils
   d) Delta formation
   e) Food articles 
   f) Blood
2. Industrial applications
   a) Electrical precipitation of smoke
   b) Purification of drinking water
   c) Colloidal medicines
   d) Photographic plates
   e) Artificial rain
   f) Rubber industry
   g) Tanning
   h) Miscellaneous

• Limitations of Werner’s theory

Coordination entity, Central atom/ion, Ligands, Colour, Shapes, Coordination number, Coordination sphere, Coordination polyhedron, Oxidation number of central atom, Homoleptic and heteroleptic complexes, charge number

• Monodentate ligands
• Polydentate ligands
• Ambidentate ligand

• Stereoisomers
• Structural isomers (Constitutional isomers)
• Optical Isomerism

• Bonding in metal carbonyls
• Structures of metal carbonyls

• Stability of coordination compounds
• Factors which govern stability of the complex

1. Charge to size ratio of the metal ion
2. Nature of the ligand
3. Stability of chelates

• Occurrence of metals
• Minerals and ores

• Pulverization
• Concentration of an ore
• Types of separation or concentration of an ore

1. Hydraulic (gravity separation) method or Levigation method
2. Magnetic separation method
3. Froth floatation
4. Chemical method or Leaching
5. Wilfley table method

• Conversion to oxide

1. Calcination
2. Roasting

• Reduction of oxide to the metal

1. Pyrometallurgy
2. Hydrometallurgy
3. Electrometallurgy

• Ellingham diagrams
• Significance of Ellingham diagram
• Limitations of Ellingham diagram
• Selection of reducing agent

• Extraction of iron from its oxides,
• Extraction of copper from cuprous oxide [copper(I) oxide]
• Extraction of zinc from zinc oxide

• Aluminium - Hall-Heroult process
• Copper from Low Grade Ores and Scraps

• Principles and methods of extraction - Refining

1. Distillation
2. Liquation 
3. Electrolytic refining (electrolytic method)
4. Zone refining
5. Vapour phase refining
6. Chromatographic methods

• Classification On the Basis of Number of Halogen Atoms
• Classification on the basis of Compounds Containing sp³ C—X Bond (X = F, Cl, Br, I)
• Classification on the basis of Compounds Containing sp² C—X Bond

1. From Alcohols
2. From hydrocarbons
   - From alkanes by free radical halogenation
   - From Alkenes - Addition of hydrogen haldies, Addition halogens) 
3. Halogen exchange (Finkelstein reaction, Swarts reaction)

1. From hydrocarbons by electrophilic substitution
2. From amines by Sandmeyer’s reaction

• Melting and boiling points
• Density
• Solubility

1. Dichloromethane (Methylene chloride)
2. Trichloromethane (Chloroform)
3. Triiodomethane (Iodoform)
4. Tetrachloromethane (Carbon tetrachloride)
5. Freons
6. p,p’-Dichlorodiphenyltrichloroethane (DDT)

• Environmental effects of polyhalogen compounds

• Occurrence
• Electronic Configuration
• Atomic and Ionic Radii
• Ionisation Enthalpy
• Electronegativity
• Physical Properties and Chemical Properties

Occurrence, Electronic Configuration, Atomic and Ionic Radii, Ionisation Enthalpy, Electron Gain Enthalpy, Electronegativity, Physical Properties and Chemical Properties (Oxidation states and trends in chemical reactivity and Anomalous behaviour of oxygen)

Occurrence, Electronic Configuration, Atomic and Ionic Radii, Ionisation Enthalpy, Electron Gain Enthalpy, Electronegativity, Physical Properties and Chemical Properties (Oxidation states and trends in chemical reactivity and Anomalous behaviour of fluorine)

• Alcohols - Mono, Di, Tri or Polyhydric alcohols

1. Monohydric alcohols
   (i) Compounds containing C_sp³ - OH bond
   - Primary, secondary and tertiary alcohols
   - Allylic alcohols
   - Benzylic alcohols
   (ii) Compounds containing C_sp² - OH bond

• Phenols - Mono, Di and trihydric phenols

• Simple or Symmetrical
• Mixed or Unsymmetrical

• From alkenes
  (i) By acid catalysed hydration: Mechanism of dehydration
  (ii) By hydroboration-oxidation
• From carbonyl compounds
  (i) By reduction of aldehydes and ketones
  (ii) By reduction of carboxylic acids and esters
• From Grignard reagents

• From chlorobenzene: Dow's method (Commercial method)
• From benzene sulphonic acid
• From diazonium salts
• From cumene (Commercial method)
• From Aniline (Diazotization method)

• Boiling Points
• Solubility

• Chemical Properties of Phenol

1. Reactions involving cleavage of O-H bond: Reaction with metals, Esterification, Acetylation
2. Electrophilic aromatic substitution reactions of phenol
   (i) Nitration
   (ii) Halogenation (bromination)
3. Kolbe's reaction
4. Reimer-Tiemann reaction
5. Reaction of phenol with zinc dust
6. Catalytic hydrogenation
7. Oxidation reaction

• Distinguishing test between alcohols and phenols
• Differentiation between alcohols and phenols

• Methanol
• Ethanol

• Preparation of ethers

1. Inter molecular dehydration of alcohol
2. Williamson's synthesis

• Methylation of alcohol
• Physical Properties of ethers
• Chemical Properties of ethers
• Uses of ethers

• Electrophilic Substitution

1. Halogenation
2. Friedel-Crafts reaction
3. Nitration

1. By oxidation of alcohols
2. By dehydrogenation of alcohols
3. From hydrocarbons
   (i) By ozonolysis of alkenes
   (ii) By hydration of alkynes

• Classification of mono and di carboxylic acids with examples.

• Classification of amines

1. Aliphatic amines
2. Aromatic amines

• Introduction 
• alkyl cyanides and alkyl isocyanides

1. Alkyl cyanides - Preparation, Properties, and reactions
2. Alkyl isocyanides: Preparation, Properties, and reactions

• Introduction
• Resonance structure 
• Method of preparation of Diazonium salts
• Physical properties 
• Chemical reactions

1. Replacement reactions involving loss of nitrogen 
2. Reactions involving retention of diazo group

• Classification of carbohydrates

• On the basis of hydrolysis

1. Simple carbohydrates
   i) Monosaccharides: Aldoses and Ketoses
2. Complex carbohydrates
   i) Oligosaccharides: Disaccharides, Trisaccharides, Tetrasaccharides
   ii) Polysaccharides: Homopoly-saccharides and Heteropoly-saccharides

• On the basis of solubility

1. Sugars: Reducing and Non-reducing sugars
2. Non-sugars

• Classification and functions of vitamins 

• Structure of DNA
• Structure of RNA
• Differences between DNA and RNA

Chemical Coordination

1. Autocrine 
2. Paracrine 
3. Endocrine 
4. Pheromone 

• Mechanism of Addition Polymerisation
  1) Free radical mechanism
• Some Important Addition Polymers
  (a) Polythene
  (i) Low density polythene
  (ii) High density polythene
  (b) Polytetrafluoroethene (Teflon)
  (c) Polyacrylonitrile

• Condensation Polymerisation or Step Growth Polymerisation
• Some Important Condensation Polymers
  (a) Polyamides: Nylons
  (i) Nylon 6, 6
  (ii) Nylon 6
  (b) Polyesters
  (c) Phenol - formaldehyde polymer (Bakelite and related polymers)
  (d) Melamine - formaldehyde polymer

• Natural rubber (Vulcanisation of rubber),
• Synthetic rubbers

1. Buna-S rubber
2. Buna-N rubber or nitrile rubber
3. Neoprene rubber

• Poly β-hydroxybutyrate – co-β-hydroxy valerate (PHBV)
• Nylon 2– nylon 6
• Biodegradable and non-biodegradable polymers

Polypropene, Polystyrene, Polyvinyl chloride (PVC), Urea-formaldehyle Resin, Glyptal, Bakelite

• Classification of Drugs
  (a) On the basis of pharmacological effect
  (b) On the basis of drug action
  (c) On the basis of chemical structure
  (d) On the basis of molecular targets

• Catalytic action of enzymes
• Drug-enzyme interaction

• Tranquilizers
• Analgesics
  (i) Non-narcotic (non-addictive) analgesics
  (ii) Narcotic analgesics

• Antibiotics
• Antiseptics and disinfectants

• Artificial Sweetening Agents
• Food Preservatives
• Antioxidants in Food

• Types of soaps
• Why do soaps not work in hard water?

• Anionic Detergents
• Cationic Detergents
• Non-ionic Detergents