Chemistry notes for Class 11, Class 12, JEE and NEET
Chemistry notes for Class 11, JEE and NEET, topic by topic: physical, inorganic and organic chemistry, solved examples, common mistakes and practice.
21 chapters 170 topics Updated 8 Nov 2026
Chapters
Some Basic Concepts of Chemistry
NCERT Class 11 Chemistry, Chapter 1 10 topics
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Importance of chemistry
Medicines, fertilisers, new materials, industry and the environment, with NCERT’s history of chemistry.
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Nature of matter
The three states and the classification of matter into mixtures, elements and compounds, with solved examples.
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Properties of matter
Physical and chemical properties, SI units, mass, volume, density and temperature scales, with solved examples.
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Uncertainty in measurement
Scientific notation, significant figures, precision, accuracy, rounding and the unit factor method.
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Laws of chemical combination
Conservation of mass, definite and multiple proportions, Gay-Lussac and Avogadro.
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Dalton’s atomic theory
The four postulates, how they explain the laws of chemical combination, and where the theory fails.
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Atomic and molecular masses
The carbon-12 scale, average atomic mass from isotopes, and formula mass, with solved examples.
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Mole concept
Avogadro number, molar mass and the formulas linking mass, moles, particles and gas volume, with solved examples.
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Percentage composition
Mass per cent of elements, empirical and molecular formulas, with NCERT examples worked step by step.
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Stoichiometry
Balancing equations, mole ratios, the limiting reagent, mass per cent, mole fraction, molarity and molality.
Structure of Atom
NCERT Class 11 Chemistry, Chapter 2 6 topics
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Sub-atomic particles
Cathode rays, Thomson’s e/m experiment, Millikan’s oil drop, canal rays and Chadwick’s neutron.
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Atomic models
Thomson’s plum pudding model, Rutherford’s gold foil experiment and nuclear model, mass number, isotopes and isobars.
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Developments leading to Bohr’s model
Work function, dual nature of light, hydrogen spectrum and solved examples.
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Bohr’s model
Postulates, derivation of orbit radius and energy, hydrogen-like ions, the hydrogen spectrum and limitations.
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Towards the quantum mechanical model
Dual nature of matter, NCERT problems and why Bohr’s model fails.
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Quantum mechanical model
Quantum numbers, shapes and nodes of s, p and d orbitals, the n + l rule, aufbau, Pauli and Hund, and electronic configurations for Class 11, JEE and NEET.
Classification of Elements and Periodicity in Properties
NCERT Class 11 Chemistry, Chapter 3 7 topics
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Why classify elements?
Why do we need to classify elements? There are too many to study one by one; a classification organises known facts and predicts new ones, for Class 11.
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Genesis of periodic classification
Mendeleev’s periodic table and the attempts before it: Döbereiner’s triads, Newlands’ octaves, and Mendeleev’s gaps and predictions, for Class 11.
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Modern periodic law
How Moseley showed atomic number sets the order, and the modern periodic table’s 7 periods and 18 groups.
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Naming elements above 100
Digit roots, “ium”, three-letter symbols like Ubn, and official names up to 118.
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Configurations and the periodic table
Electronic configuration and the periodic table: why periods hold 2, 8, 8, 18, 18, 32 and 32 elements, and how to find an element’s period and group.
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s, p, d and f blocks
Outer configurations, properties, the places of H and He, and metals, non-metals and metalloids.
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Periodic trends
Atomic and ionic radii, ionisation enthalpy, electron gain enthalpy, electronegativity.
Chemical Bonding and Molecular Structure
NCERT Class 11 Chemistry, Chapter 4 10 topics
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Kössel–Lewis approach
The Kössel–Lewis approach, Lewis symbols, writing Lewis structures, formal charge and the rule’s exceptions.
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Ionic bond
Electron transfer, factors favouring an ionic (electrovalent) bond, lattice enthalpy and the Born–Haber cycle.
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Bond parameters
Bond length, angle, enthalpy and order, resonance, dipole moment and Fajans’ rules, with solved examples.
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VSEPR theory
Postulates, shapes of molecules with and without lone pairs and bond angles, with solved examples.
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Valence bond theory
Valence bond theory: how H forms, positive, negative and zero orbital overlap, sigma and pi bonds and their strength, for Class 11, JEE and NEET.
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Hybridisation
Sp, sp, sp, spd and spd with shapes and bond angles, the steric number shortcut and solved examples.
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Molecular orbital theory
Molecular orbital theory: LCAO, bonding and antibonding orbitals, the two MO energy orders, bond order and magnetism, for Class 11, JEE and NEET.
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Homonuclear diatomic molecules
MO configurations, bond orders and magnetism of H to Ne, and why O is paramagnetic.
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Hydrogen bonding
Its cause, intermolecular and intramolecular types with examples, and effects on boiling point and density.
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Metallic bonding
Metallic bonding: positive ion cores in a sea of delocalised electrons, what makes it strong, and why metals conduct, shine and bend, for JEE and NEET.
Thermodynamics
NCERT Class 11 Chemistry, Chapter 5 9 topics
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Thermodynamic terms
Thermodynamic terms: system and surroundings, open, closed and isolated systems, state functions, internal energy, first law, for Class 11, JEE and NEET.
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Work, enthalpy and heat capacity
H = U + pV, ΔH = ΔU + ΔngRT, pressure–volume work, free expansion and heat capacity, with solved examples.
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Calorimetry
How a bomb calorimeter gives ΔU and a coffee-cup calorimeter ΔH, and how to convert between them.
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Reaction enthalpy and Hess’s law
Standard states, reaction enthalpy, phase changes and thermochemical equations.
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Combustion, bond and lattice enthalpies
Bond enthalpy, lattice enthalpy and the Born–Haber cycle, with combustion, atomisation, solution and dilution enthalpies, for Class 11, JEE and NEET.
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Enthalpy of neutralization
Why strong acids and bases give about −57 kJ mol, weak acids, the calorimeter method and solved examples.
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Experiment: enthalpy of solution of copper sulphate
The calorimeter method, why the crystals cool water, the Hess cycle and solved examples.
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Spontaneity, entropy and Gibbs energy
Why a fall in enthalpy is not enough, entropy, Gibbs free energy ΔG = ΔH − TΔS and the third law.
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Gibbs energy and equilibrium
Why G is a minimum at equilibrium, ΔG° = −RT ln K and the 5.71 kJ rule.
Equilibrium
NCERT Class 11 Chemistry, Chapter 6 14 topics
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Equilibrium in physical processes
Solid–liquid, liquid–vapour and solid–vapour equilibria, vapour pressure, Henry’s law and solved examples.
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Dynamic equilibrium in chemical processes
Reversible reactions, equal forward and reverse rates, reaching equilibrium from both sides, the D test.
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Law of chemical equilibrium and equilibrium constant
Law of mass action, writing Kc for any reaction, reversed and multiplied equations, solved examples.
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Homogeneous equilibria
Homogeneous equilibria, Kp = Kc(RT)Δn derived, Δn, units of K, and NCERT Problems 6.3–6.5 solved.
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Heterogeneous equilibria
Why pure solids and liquids are left out of K, CaCO ⇌ CaO + CO, and NCERT Problem 6.6 solved.
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Applications of equilibrium constants
Extent of reaction from K, direction from Q and equilibrium concentrations, step by step.
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Equilibrium constant, reaction quotient and Gibbs energy
ΔG = ΔG° + RT ln Q, ΔG° = −RT ln K, the direction of reaction and NCERT Problems 6.10–6.11.
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Factors affecting equilibria
Effects of concentration, pressure, inert gas, temperature and catalyst on equilibrium, with examples.
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Ionic equilibrium in solution
Electrolytes, strong and weak electrolytes, ionisation in water, the dielectric constant and hydration.
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Acids, bases and salts
Conjugate acid–base pairs, amphiprotic species and NCERT problems solved.
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Ionization of acids and bases
Polybasic acids, common ion effect, hydrolysis of salts and 10 NCERT problems solved.
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Experiment: acid-base titration with an indicator
Standard solutions, the burette, phenolphthalein or methyl orange, end point and a1M1V1 = a2M2V2, solved examples.
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Buffer solutions
How buffers resist pH change, the Henderson–Hasselbalch equation, and worked acetate and ammonia buffers.
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Solubility equilibria of sparingly soluble salts
Ksp and molar solubility, precipitation from Qsp, the common ion effect and pH, NCERT problems solved.
Redox Reactions
NCERT Class 11 Chemistry, Chapter 7 4 topics
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Classical idea of oxidation and reduction
Classical definitions by oxygen and hydrogen, oxidising and reducing agents, NCERT Problem 7.1 solved.
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Redox reactions as electron transfer
Oxidation as loss of electrons, half reactions and the Zn, Cu, Ag order, with examples.
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Oxidation number
How to find it with the rules, Stock notation, types of redox reactions, balancing and titrations, solved.
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Redox reactions and electrode processes
Redox couples, salt bridge, anode and cathode signs and the E° table, solved.
Organic Chemistry: Some Basic Principles and Techniques
NCERT Class 11 Chemistry, Chapter 8 10 topics
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General introduction to organic chemistry
What it studies, catenation, the vital force theory, Wöhler’s synthesis of urea, Kolbe and Berthelot, with solved examples.
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Tetravalence of carbon and shapes
Sp, sp and sp shapes, s character, π bonds and restricted rotation, with NCERT problems solved.
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Structural representations
Complete, condensed and bond-line formulas, wedge-dash 3-D drawings and molecular models, with problems.
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Classification of organic compounds
Acyclic, alicyclic and aromatic compounds, functional groups and homologous series.
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IUPAC nomenclature of organic compounds
Naming rules for branched alkanes, functional group priority, rings and benzene derivatives, with examples.
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Isomerism
Chain, position and functional group isomers, metamers, geometrical and optical isomerism, with solved examples.
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Organic reaction mechanism
Bond fission, carbocations, nucleophiles, inductive and resonance effects, hyperconjugation.
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Purification of organic compounds
Sublimation, crystallisation, simple, fractional and steam distillation, TLC and Rf values.
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Qualitative analysis of organic compounds
Tests for C, H, N, S, halogens and P, with solved examples.
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Quantitative analysis
Estimating C, H, N (Dumas, Kjeldahl), halogens, S, P and O, with NCERT problems.
Hydrocarbons
NCERT Class 11 Chemistry, Chapter 9 6 topics
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Classification of hydrocarbons
Saturated, unsaturated and aromatic, general formulas, fuels and degree of unsaturation.
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Alkanes
Isomers, Wurtz, Kolbe and decarboxylation, free radical halogenation, combustion and the conformations of ethane.
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Alkenes
The C=C bond, cis-trans isomerism, preparation, Markovnikov’s rule, the peroxide effect and ozonolysis.
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Alkynes
Naming, the triple bond, preparation, acidic character of terminal alkynes, addition reactions and polymerisation.
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Aromatic hydrocarbons
Benzene’s structure, Hückel’s rule, electrophilic substitution and the directive influence of groups.
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Carcinogenicity and toxicity
Benzene and polynuclear aromatic hydrocarbons, their sources and how they damage DNA.
Solutions
NCERT Class 12 Chemistry, Chapter 1 7 topics
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Types of solutions
Solvent and solute, binary solutions and the nine gaseous, liquid and solid types, with examples.
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Concentration of solutions
Mass, volume and w/V percentage, ppm, mole fraction, molarity, molality, conversions and examples.
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Solubility
Like dissolves like, saturated solutions, effect of temperature and pressure, and Henry’s law, its formula and uses.
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Vapour pressure of solutions
Vapour pressure of liquid solutions, the total pressure formula, vapour composition and non-volatile solutes.
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Ideal and non-ideal solutions
Raoult’s law, positive and negative deviations with graphs, causes, examples and azeotropes.
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Colligative properties
Vapour pressure lowering, ΔTb, ΔTf, Kb, Kf, osmosis, isotonic solutions, reverse osmosis, molar mass.
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Abnormal molar masses
Abnormal molar mass, modified colligative formulas, degree of association and dissociation, examples.
Electrochemistry
NCERT Class 12 Chemistry, Chapter 2 8 topics
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Electrochemical cells
The Daniell cell, galvanic vs electrolytic cells, anode and cathode signs, a diagram and solved examples.
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Galvanic cells
Half-cells, salt bridge, cell notation, emf, the standard hydrogen electrode and standard electrode potentials.
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Nernst equation
The formula at 298 K, its derivation, K and ΔG from the emf, and solved numericals from NCERT.
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Conductance of electrolytic solutions
Unit, cell constant, strong vs weak electrolytes, Kohlrausch’s law, examples.
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Electrolytic cells and electrolysis
Electrolytic cells, Faraday’s laws, the faraday, mass deposited, and the products of electrolysis of brine.
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Batteries
Primary vs secondary cells, dry and mercury cells, lead storage battery reactions and diagram, nickel-cadmium cell.
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Fuel cells
The hydrogen–oxygen fuel cell, its reactions and diagram, efficiency against thermal plants, the hydrogen economy.
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Corrosion
Rusting of iron as an electrochemical cell, its electrode reactions, and prevention by paint, galvanising or sacrificial metals.
Chemical Kinetics
NCERT Class 12 Chemistry, Chapter 3 6 topics
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Rate of a chemical reaction
Average and instantaneous rate, units, the balanced equation and partial pressures, with solved examples.
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Factors influencing rate
Factors affecting rate, rate law and rate constant, units of k, molecularity and the rate determining step.
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Experiment: iodide and hydrogen peroxide
Iodide and HO in acid, the procedure, timing the blue with thiosulphate and starch, and the effect of iodide.
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Integrated rate equations
Zero and first order reactions, their graphs and half-lives, gas phase k and pseudo first order.
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Temperature dependence of rate
Effect of temperature on rate, activation energy, ln k against 1/T, Maxwell–Boltzmann curve and catalysts.
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Collision theory
Collision frequency, effective collisions, threshold energy, orientation and the steric factor P.
The p-Block Elements
6 topics
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Group 13 elements
Configuration, oxidation states, inert pair effect, trends, properties, boron’s anomaly and examples.
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Group 14 elements
Configuration, +4 and +2 states, inert pair effect, trends, oxides, halides and carbon’s anomaly.
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Group 15 elements
Configuration, −3, +3, +5 states, trends, hydrides, oxides, halides and nitrogen’s anomaly.
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Group 16 elements
Configuration, −2 to +6 states, trends, hydrides, oxides, SF and oxygen’s anomaly.
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Group 17 elements
Configuration, oxidation states, trends, oxidising power, HX acids, interhalogens, fluorine’s anomaly.
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Group 18 elements
Configuration, trends, low reactivity, xenon fluorides XeF, XeF, XeF, their shapes, XeO and helium.
The d- and f-Block Elements
NCERT Class 12 Chemistry, Chapter 4 9 topics
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Position in the periodic table
Groups 3–12, the 3d, 4d, 5d and 6d series, why they are called transition elements, and the f-block below.
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Electronic configurations
(n − 1)d ns, the chromium and copper exceptions, ions, and Zn, Cd and Hg.
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Occurrence
How transition metals occur, native metals, and the metal in each pure ore.
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General properties
Radii, ionisation enthalpy, oxidation states, E⊖, magnetic moment, colour, catalysis.
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Important compounds
Preparation from ores, structures, reactions in acid and alkali, and uses.
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Experiment: KMnO₄ titrations
Permanganate as its own indicator, oxalic acid at 333 K, Mohr’s salt unheated, the aMV = aMV rule and precautions.
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Lanthanoids
4f configurations, the lanthanoid contraction, its cause and consequences, oxidation states and magnetism.
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Actinoids
5f configurations, the actinoid contraction, oxidation states from +3 to +7, and a comparison with lanthanoids.
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Applications
Iron and steels, TiO pigment, MnO in dry cells, coinage metals, AgBr and catalysts such as VO.
Coordination Compounds
NCERT Class 12 Chemistry, Chapter 5 8 topics
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Werner’s theory
Postulates, primary and secondary valency, the AgCl test, and double salts vs complexes, with solved examples.
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Experiment: double salts
Double salts from equimolar mixtures, why dilute HSO is added, procedure and precautions.
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Ligands and other terms
Denticity, chelates, ambidentate ligands, coordination number, sphere and polyhedron, oxidation number, with examples.
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Nomenclature
Rules for formulas and names, ligand names, -ate anions, with worked examples.
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Isomerism
Geometrical (cis, trans, fac, mer), optical, linkage, coordination, ionisation and solvate.
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Bonding: VBT and CFT
Inner and outer orbital complexes, magnetism, high and low spin, spectrochemical series, colour.
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Metal carbonyls
Homoleptic carbonyls and their shapes, σ donation, back bonding and synergic bonding in the M–CO bond.
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Importance and applications
Qualitative analysis, EDTA and hardness, gold and nickel, haemoglobin, cis-platin.
Haloalkanes and Haloarenes
NCERT Class 12 Chemistry, Chapter 6 8 topics
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Classification
Mono-, di-, polyhalogen; 1°, 2°, 3°, allylic, benzylic, vinylic and aryl halides.
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Nomenclature
Common and IUPAC names, o-, m-, p- or 1,2-, 1,3-, 1,4-, gem and vic dihalides.
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Nature of C–X bond
Why it is polar, and NCERT Table 6.2’s bond lengths, bond enthalpies and dipole moments.
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Preparation of haloalkanes
From alcohols (HX, PX, PCl, SOCl), alkanes and alkenes, and the Finkelstein and Swarts reactions.
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Preparation of haloarenes
Electrophilic substitution with Fe or FeCl, why iodine and fluorine differ, Sandmeyer’s reaction.
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Physical properties
Boiling point order, branching, para isomers, density and solubility.
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Chemical reactions
SN1 vs SN2, chirality, Saytzeff, Grignard, Wurtz–Fittig, haloarene reactivity.
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Polyhalogen compounds
Uses and effects of CHCl, chloroform, iodoform, CCl, freons and DDT, and why chloroform is kept dark.
Alcohols, Phenols and Ethers
NCERT Class 12 Chemistry, Chapter 7 7 topics
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Classification
Mono- to polyhydric; 1°, 2°, 3°, allylic, benzylic, vinylic; symmetrical ethers.
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Nomenclature
Common and IUPAC names, -ol and -diol, cresols, benzenediols, alkoxy names.
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Structures of functional groups
C–O–H and C–O–C angles, C–O bond lengths and why phenol’s C–O bond is shorter.
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Alcohols and phenols
Preparation, phenol from cumene, acidity and pKa, Lucas test, dehydration, oxidation and Kolbe’s reaction.
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Experiment: tests for –OH groups
Ceric ammonium nitrate, the Lucas and iodoform tests, neutral ferric chloride and the phthalein dye test.
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Commercially important alcohols
Methanol from CO and hydrogen, ethanol by fermentation, their uses, methanol poisoning and denaturation.
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Ethers
Dehydration of alcohols, Williamson synthesis, boiling points, cleavage by HI and electrophilic substitution in anisole.
Aldehydes, Ketones and Carboxylic Acids
NCERT Class 12 Chemistry, Chapter 8 13 topics
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Carbonyl group: names and structure
Common and IUPAC names (NCERT Table 8.1), how the two differ, and why the C=O group is planar and polar.
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Preparation of aldehydes and ketones
Rosenmund, Stephen, Etard and Gattermann–Koch reactions, DIBAL-H, RCd and Friedel–Crafts.
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Physical properties of aldehydes and ketones
Boiling points against alkanes, ethers and alcohols, and solubility in water.
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Reactions of aldehydes and ketones
Nucleophilic addition, reductions, Tollens’ test, aldol, Cannizzaro and haloform.
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Experiment: tests for aldehydes and ketones
2,4-DNP for the carbonyl group, then Schiff’s, Fehling’s, Benedict’s and Tollens’ for aldehydes.
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Experiment: preparation of iodoform
The haloform reaction of acetone or ethanol with iodine and alkali, Remsen’s 1903 method and the yellow crystals.
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Uses of aldehydes and ketones
Formalin and bakelite, acetaldehyde as a starting material, solvents, perfumes and flavours.
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Carboxyl group: names and structure
Common and IUPAC names (NCERT Table 8.3), dioic acids, and how –COOH differs from a carbonyl group.
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Preparation of carboxylic acids
Oxidising alcohols and alkylbenzenes, nitriles, Grignard reagents with CO, and hydrolysis.
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Physical properties of carboxylic acids
Hydrogen-bonded dimers, high boiling points, and solubility in water.
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Chemical reactions of carboxylic acids
Acidity and substituents, esterification, acyl chlorides, reduction, decarboxylation and HVZ.
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Experiment: tests for the carboxyl group
Blue litmus, effervescence with sodium hydrogencarbonate, and the sweet-smelling ester test.
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Uses of carboxylic acids
Formic and acetic acid, vinegar, nylon-6,6, sodium benzoate, and soaps from fatty acids.
Amines
NCERT Class 12 Chemistry, Chapter 9 13 topics
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Structure of amines
Amines as derivatives of ammonia, the sp hybridised nitrogen, its lone pair and the pyramidal shape.
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Classification of amines
Primary, secondary and tertiary amines, simple and mixed amines, with NCERT’s examples.
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Nomenclature of amines
Common and IUPAC names, alkanamines and aniline, diamines, N-locants and the isomers of CHN.
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Preparation of amines
Reducing nitro compounds, nitriles and amides, ammonolysis, Gabriel synthesis and Hofmann degradation.
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Physical properties of amines
Odour, solubility in water, hydrogen bonding and the boiling points of 1°, 2° and 3° amines.
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Chemical reactions of amines
Basicity, pKb, carbylamine and Hinsberg tests, nitrous acid, bromination and nitration of aniline.
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Experiment: tests for the amino group
Test for amino group for JEE and NEET practical chemistry: solubility in dilute HCl, the carbylamine test and the azo dye test, and what each result shows.
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Experiment: preparation of acetanilide and p-nitroacetanilide
Acetylating aniline, nitrating below 10 °C, recrystallisation, melting points, yield.
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Preparation of diazonium salts
Diazotisation of aniline with NaNO and HCl at 273–278 K, why it is kept cold, and naming.
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Physical properties of diazonium salts
The colour, solubility and stability of benzenediazonium chloride and fluoroborate.
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Chemical reactions of diazonium salts
Sandmeyer and Gattermann reactions, replacement by I, F, H, OH and NO, and azo coupling.
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Experiment: preparation of aniline yellow
Diazotisation, coupling with aniline, the diazoaminobenzene route and safety.
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Diazonium salts in the synthesis of aromatic compounds
Making aryl fluorides, iodides and nitriles, removing –NH, and NCERT Example 9.5 step by step.
Biomolecules
NCERT Class 12 Chemistry, Chapter 10 6 topics
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Carbohydrates
Classification, glucose and fructose structures, anomers, sucrose, maltose and lactose, starch and cellulose.
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Proteins
Amino acids and zwitter ions, essential amino acids, the peptide bond, four levels of structure and denaturation.
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Enzymes
Biocatalysts, specificity, naming, activation energy, and the enzyme–substrate complex mechanism, with solved examples.
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Vitamins
Fat-soluble and water-soluble vitamins, their sources and the diseases caused by their deficiency, from NCERT.
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Nucleic acids
DNA and RNA composition, nucleosides and nucleotides, the double helix, base pairing and DNA fingerprinting.
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Hormones
Intercellular messengers, steroid, polypeptide and amino acid derivative hormones, and what insulin and thyroxine do.
Practical Chemistry
3 topics
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Experiment: preparation of lyophilic and lyophobic sols
Egg albumin, starch and gum sols, and iron(III) and aluminium hydroxide sols, from NCERT.
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Experiment: salt analysis, anions
Dilute and concentrated sulphuric acid groups, sulphate, and the confirmatory tests with equations.
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Experiment: salt analysis, cations
Group reagents for groups zero to VI and confirmatory tests for each syllabus cation, with equations.