Chemistry Notes for NEET and JEE Main 2027: Chapter-wise Key Points

These Chemistry notes for NEET and JEE Main 2027 give the high-yield points of 15 Physical, Inorganic and Organic Chemistry chapters from Class 11 and 12, with a free notes PDF and a notes page for each. They follow the Chemistry units of the NEET UG 2026 and JEE Main 2026 syllabi, which apply until the 2027 syllabi are out.

Chemistry Notes for NEET and JEE Main 2027

Chapter-wise key points and notes PDFs for NEET UG and JEE Main 2027 Chemistry, grouped into Physical, Inorganic and Organic Chemistry.

How are these Chemistry notes arranged?

Both exams use the same 20 Chemistry units, numbered the same way: the NEET UG 2026 syllabus released by the National Medical Commission (NMC) on 22 December 2025 and the JEE Main 2026 syllabus released by the National Testing Agency (NTA) on 31 October 2025. Units 1 to 8 are Physical Chemistry, Units 9 to 12 Inorganic Chemistry and Units 13 to 20 Organic Chemistry. The notes will be matched to the 2027 syllabi once they are released. See the NEET syllabus and the JEE Main syllabus for the full topic lists.

The 15 chapters below are grouped into Physical, Inorganic and Organic Chemistry. Within each group, Class 11 chapters come first and then Class 12, with names and numbering from the current rationalised NCERT Chemistry textbooks. Each chapter has a short set of key points here, a detailed notes page (click the chapter name) and a notes PDF. p-Block Elements is the one exception: it is still in both syllabi but is no longer in the NCERT books, so its notes follow the syllabus and the older NCERT editions.

Seven chapters of the older NCERT books are in neither the NEET UG 2026 nor the JEE Main 2026 syllabus, so they have been removed from this page: States of Matter, Solid State, Surface Chemistry, Hydrogen, s-Block Elements, Polymers and Nuclear Chemistry (once taught with Chemical Kinetics). The notes PDFs were made for the older NCERT books, so skip any of these topics if they appear in a PDF.

Chemistry Notes PDF: Chapter-wise Download

Each PDF has key notes and important questions with answers for the chapter and opens free on AglaSem Docs.

Physical Chemistry Notes PDF

Inorganic Chemistry Notes PDF

Organic Chemistry Notes PDF

Physical Chemistry Key Points: Chapter-wise Summary

These 7 chapters cover Units 1 to 8 of the syllabus except Unit 3 (Chemical Bonding), which is coming soon. Class 11 chapters come first, then Class 12.

Some Basic Concepts of Chemistry (Unit 1, Class 11)

This chapter covers the laws of chemical combination, atomic and molecular mass, the mole concept, empirical formulae, stoichiometry and concentration terms.

• 1 u (amu) is 1/12 of the mass of one carbon-12 atom; the Avogadro constant NA is 6.02214076 × 10²³ mol⁻¹ (exact).
• Laws of chemical combination: conservation of mass (Lavoisier), definite proportions (Proust), multiple proportions (Dalton), gaseous volumes (Gay Lussac) and Avogadro’s law.
• Molecular formula = n × empirical formula, where n = molar mass ÷ empirical formula mass.
• The limiting reagent is used up first and fixes the amount of product formed.
• Molality and mole fraction do not change with temperature; molarity does. For dilution, M₁V₁ = M₂V₂.

Notes PDF: View notes PDF.

Structure of Atom (Unit 2, Class 11)

This chapter covers the discovery of subatomic particles, Bohr’s model, the dual nature of matter, quantum numbers, orbital shapes and electronic configuration.

• E = hν. In the photoelectric effect hν = hν₀ + ½mv², so the energy of photoelectrons depends on frequency and their number on intensity.
• Bohr model for hydrogen-like species: rₙ ∝ n²/Z and Eₙ ∝ −Z²/n². Bohr radius = 52.9 pm; E₁ of hydrogen = −2.18 × 10⁻¹⁸ J.
• de Broglie: λ = h/mv. Heisenberg: Δx·Δp ≥ h/4π.
• Orbitals in a shell = n² and in a subshell = 2l + 1; radial nodes = n − l − 1 and angular nodes = l.
• Exceptional configurations: Cr is [Ar]3d⁵4s¹ and Cu is [Ar]3d¹⁰4s¹, because half-filled and completely filled subshells are extra stable.

Notes PDF: View notes PDF.

Thermodynamics (Unit 4, Class 11)

This chapter covers the first law, work and enthalpy, Hess’s law, entropy and Gibbs energy.

• First law: ΔU = q + w. U, H, S and G are state functions; q and w are path functions.
• ΔH = ΔU + Δn(g)RT, counting only gaseous species. ΔU is measured at constant volume (bomb calorimeter) and ΔH at constant pressure.
• Isothermal reversible expansion of an ideal gas: w = −2.303 nRT log(Vf/Vi); free expansion: w = 0.
• Hess’s law: the total enthalpy change is the same whatever the path. ΔfH° of an element in its reference state (graphite, rhombic sulphur) is zero.
• ΔG = ΔH − TΔS; ΔG < 0 means a spontaneous change at constant T and p, and ΔrG° = −2.303 RT log K.

Notes PDF: View notes PDF.

Equilibrium (Unit 6, Class 11)

This chapter covers chemical equilibrium, Kc and Kp, Le Chatelier’s principle and ionic equilibrium: acids, bases, pH, salt hydrolysis, buffers and Ksp.

• Kp = Kc(RT)^Δn, where Δn counts gaseous species only. Pure solids and liquids do not appear in K.
• If Qc < Kc the reaction moves forward; if Qc > Kc it moves backward. Only temperature changes the value of K; a catalyst only helps reach equilibrium faster.
• Kw = 1.0 × 10⁻¹⁴ at 298 K, so pH + pOH = 14; for a conjugate acid-base pair Ka × Kb = Kw.
• A salt of a weak acid and strong base (CH₃COONa) gives a basic solution; a salt of a strong acid and weak base (NH₄Cl) gives an acidic one.
• For a salt AₓBᵧ, Ksp = xˣyʸS^(x+y); a common ion lowers the solubility of a sparingly soluble salt.

Notes PDF: View notes PDF.

Solutions (Unit 5, Class 12)

This chapter covers concentration terms, Raoult’s law, ideal and non-ideal solutions, colligative properties and the van’t Hoff factor.

• Molality, mole fraction and mass percentage do not depend on temperature; molarity does.
• Raoult’s law for a non-volatile solute: the relative lowering of vapour pressure equals the mole fraction of the solute.
• Ideal solutions have ΔmixH = 0 and ΔmixV = 0 (benzene + toluene). Ethanol + acetone shows positive deviation; chloroform + acetone shows negative deviation.
• Colligative properties: ΔTb = Kb·m, ΔTf = Kf·m and Π = CRT. For water, Kb = 0.52 and Kf = 1.86 K kg mol⁻¹.
• van’t Hoff factor i: dissociation (i about 2 for KCl) lowers the measured molar mass; association (i about 0.5 for ethanoic acid in benzene) raises it.

Notes PDF: View notes PDF.

Electrochemistry (Unit 7, Class 12)

This chapter covers galvanic and electrolytic cells, electrode potential, the Nernst equation, conductance, Kohlrausch’s law and batteries.

• E°cell = E°cathode − E°anode. The Daniell cell gives 1.10 V; the standard hydrogen electrode has E° = 0 at all temperatures.
• Nernst equation at 298 K: Ecell = E°cell − (0.059/n) log Q. Also ΔrG° = −nFE°cell = −RT ln K, with 1 F ≈ 96500 C mol⁻¹.
• On dilution, conductivity falls but molar conductivity rises. Λm = Λ°m − A√c holds only for strong electrolytes.
• For a weak electrolyte, Λ°m comes from Kohlrausch’s law and the degree of dissociation α = Λm/Λ°m.
• The dry cell gives about 1.5 V; the lead storage battery uses 38% H₂SO₄, and both electrodes turn to PbSO₄ on discharge.

Notes PDF: View notes PDF.

Chemical Kinetics (Unit 8, Class 12)

This chapter covers rate of reaction, rate law, order and molecularity, zero and first order reactions, half-life and the Arrhenius equation.

• The rate law is found by experiment. Order can be zero or fractional; molecularity is only 1, 2 or 3 and applies only to elementary reactions.
• Units of k: zero order mol L⁻¹ s⁻¹, first order s⁻¹, second order mol⁻¹ L s⁻¹.
• Half-life: zero order t½ = [R]₀/2k; first order t½ = 0.693/k, which does not depend on the initial concentration.
• Arrhenius equation: k = A e^(−Ea/RT); the slope of ln k against 1/T is −Ea/R. The rate constant nearly doubles for a 10° rise in temperature.
• A catalyst lowers Ea but does not change ΔG or K. Hydrolysis of an ester and inversion of cane sugar are pseudo first order reactions.

Notes PDF: View notes PDF. Skip any nuclear chemistry in it; that topic is not in either syllabus.

Inorganic Chemistry Key Points: Chapter-wise Summary

These 2 chapters cover Units 10 and 12. Units 9 (Classification of Elements and Periodicity) and 11 (d- and f-Block Elements) are coming soon.

p-Block Elements (Unit 10, Class 11 and 12, older NCERT)

This unit covers Groups 13 to 18: electronic configuration, trends in physical and chemical properties and the unique behaviour of the first element of each group. The current NCERT books dropped this chapter, but both syllabi still include it.

• Valence configuration runs from ns²np¹ (Group 13) to ns²np⁶ (Group 18). Down Groups 13 to 15 the lower oxidation state becomes more stable (inert pair effect: Tl⁺, Pb²⁺, Bi³⁺).
• B, C, N, O and F have no d orbitals, so their maximum covalency is 4; nitrogen forms no NCl₅ while phosphorus forms PCl₅.
• Oxides of Group 13: B₂O₃ is acidic, Al₂O₃ amphoteric and Tl₂O₃ basic.
• In Group 17, chlorine (not fluorine) has the most negative electron gain enthalpy; bond dissociation enthalpy is Cl₂ > Br₂ > F₂ > I₂.
• Bartlett made the first noble gas compound, Xe⁺[PtF₆]⁻. XeF₂ is linear and XeF₄ is square planar.

Notes PDF: Groups 13 and 14 notes PDF and Groups 15 to 18 notes PDF (both made for the older NCERT books).

Coordination Compounds (Unit 12, Class 12)

This chapter covers Werner’s theory, ligands, IUPAC naming, isomerism, valence bond theory, crystal field theory and metal carbonyls.

• Werner’s theory: primary valence is ionisable (oxidation state) and secondary valence is the coordination number. CoCl₃·6NH₃, CoCl₃·5NH₃ and CoCl₃·4NH₃ give 3, 2 and 1 mol of AgCl.
• EDTA⁴⁻ is hexadentate; ethane-1,2-diamine and oxalate are didentate. NO₂⁻ and SCN⁻ are ambidentate and give linkage isomers.
• Valence bond theory: [Co(NH₃)₆]³⁺ is d²sp³ and diamagnetic; [CoF₆]³⁻ is sp³d² and paramagnetic; [Ni(CN)₄]²⁻ is dsp², square planar and diamagnetic.
• Crystal field theory: Δt = (4/9)Δo; Δo > P gives low-spin complexes. In the spectrochemical series I⁻ is the weakest and CO the strongest ligand.
• Tetrahedral complexes show no geometrical isomerism. Metal carbonyls are held by synergic bonding (σ donation plus π back bonding).

Notes PDF: View notes PDF.

Organic Chemistry Key Points: Chapter-wise Summary

These 6 chapters cover Units 13 to 18. Class 11 chapters come first, then Class 12.

Organic Chemistry: Some Basic Principles and Techniques (Units 13 and 14, Class 11)

This chapter covers hybridisation, IUPAC naming, isomerism, reaction intermediates, electronic effects, purification methods and the detection and estimation of elements.

• s character: sp 50%, sp² 33%, sp³ 25%; the higher the s character, the more electronegative the carbon.
• Carbocations are sp² and planar. Carbocation and free radical stability: 3° > 2° > 1° > methyl.
• The inductive effect is permanent and fades after about three bonds; the electromeric effect is temporary; hyperconjugation is no-bond resonance.
• Purification: aniline is purified by steam distillation; paper chromatography is partition chromatography, while TLC and column chromatography are adsorption methods.
• Lassaigne’s test gives Prussian blue for nitrogen and blood red when N and S are both present. Kjeldahl’s method fails for nitro, azo and ring nitrogen (pyridine).

Notes PDF: View notes PDF.

Hydrocarbons (Unit 15, Class 11)

This chapter covers alkanes and their conformations, alkenes, alkynes, benzene, aromaticity and electrophilic substitution.

• Staggered ethane is more stable than eclipsed ethane by about 12.5 kJ mol⁻¹. Branching lowers the boiling point of alkanes.
• HX adds to unsymmetrical alkenes by Markovnikov’s rule; the peroxide (Kharash) effect gives anti-Markovnikov addition with HBr only.
• Lindlar’s catalyst reduces alkynes to cis-alkenes; sodium in liquid ammonia gives trans-alkenes.
• Ethyne is the most acidic of ethane, ethene and ethyne (sp carbon, 50% s character); its hydration with HgSO₄/H₂SO₄ gives ethanal.
• Aromatic compounds are planar with (4n + 2) π electrons (Hückel rule). –NO₂, –CN, –CHO and –COOH are meta directors; halogens deactivate the ring but direct ortho and para.

Notes PDF: View notes PDF.

Haloalkanes and Haloarenes (Unit 16, Class 12)

This chapter covers the C–X bond, preparation of haloalkanes and haloarenes, SN1 and SN2 mechanisms, elimination and polyhalogen compounds.

• SN2 is a one-step reaction with inversion of configuration (1° > 2° > 3°); SN1 goes through a carbocation and gives racemisation (3° > 2° > 1°).
• Reactivity in substitution: R–I > R–Br > R–Cl. KCN gives alkyl cyanides but AgCN gives isocyanides.
• Finkelstein reaction: NaI in dry acetone gives alkyl iodides. Swarts reaction: AgF, Hg₂F₂, CoF₂ or SbF₃ gives alkyl fluorides. SOCl₂ is the preferred reagent for converting alcohols to chlorides.
• Dehydrohalogenation follows Zaitsev’s rule: the more substituted alkene is the major product.
• Haloarenes resist nucleophilic substitution because the C–X bond has partial double bond character; an –NO₂ group at the ortho or para position makes the reaction easier.

Notes PDF: View notes PDF.

Alcohols, Phenols and Ethers (Unit 17, Class 12)

This chapter covers the preparation, acidity and reactions of alcohols, phenols and ethers.

• Hydroboration-oxidation gives the anti-Markovnikov alcohol. A Grignard reagent gives a 1° alcohol with methanal, a 2° alcohol with other aldehydes and a 3° alcohol with ketones.
• Lucas test (conc. HCl + ZnCl₂): tertiary alcohols turn turbid at once. Ease of dehydration is 3° > 2° > 1°.
• Phenol (pKa 10.0) is more acidic than ethanol (pKa 15.9) because the phenoxide ion is stabilised by resonance; o-nitrophenol is steam volatile due to intramolecular hydrogen bonding.
• Kolbe’s reaction gives salicylic acid and the Reimer-Tiemann reaction gives salicylaldehyde; bromine water gives a white precipitate of 2,4,6-tribromophenol.
• Williamson synthesis needs a primary alkyl halide. Anisole with HI gives phenol and methyl iodide.

Notes PDF: View notes PDF.

Aldehydes, Ketones and Carboxylic Acids (Unit 17, Class 12)

This chapter covers the preparation and reactions of aldehydes and ketones, tests that tell them apart, and the acidity and reactions of carboxylic acids.

• Named preparations: Rosenmund (acyl chloride + H₂, Pd-BaSO₄), Stephen (nitrile + SnCl₂/HCl), Etard (toluene + CrO₂Cl₂) and Gatterman-Koch (benzene + CO + HCl) give aldehydes.
• Aldehydes are more reactive than ketones in nucleophilic addition.
• Tollens’ reagent gives a silver mirror; Fehling’s solution gives a reddish brown precipitate but not with aromatic aldehydes. Clemmensen (Zn-Hg/conc. HCl) and Wolff-Kishner reduce C=O to CH₂.
• Aldol condensation needs an α-hydrogen and dilute alkali; the Cannizzaro reaction needs no α-hydrogen and concentrated alkali. The iodoform test detects CH₃CO– groups.
• Carboxylic acids are more acidic than phenols and release CO₂ from hydrogencarbonates; the HVZ reaction gives α-halo acids.

Notes PDF: View notes PDF.

Amines (Unit 18, Class 12)

This chapter covers the classification, preparation, basic strength and reactions of amines, and diazonium salts.

• Hoffmann bromamide degradation gives an amine with one carbon less; Gabriel phthalimide synthesis gives only primary aliphatic amines.
• Basic strength in water: (C₂H₅)₂NH > (C₂H₅)₃N > C₂H₅NH₂ > NH₃. Aniline (pKb 9.38) is a much weaker base than NH₃ (pKb 4.75).
• Only primary amines give the carbylamine test; the Hinsberg test tells primary, secondary and tertiary amines apart.
• Aniline does not undergo Friedel-Crafts reactions, and its nitration gives some meta product through the anilinium ion.
• Diazotisation is done at 273 to 278 K. Sandmeyer reaction uses Cu(I) salts; coupling of benzenediazonium chloride with phenol gives p-hydroxyazobenzene.

Notes PDF: View notes PDF.

Which Chemistry chapters are coming soon?

These syllabus chapters do not have a notes page yet. Study them from the NCERT textbook until the notes are added:

• Chemical Bonding and Molecular Structure (Unit 3, Class 11)
• Redox Reactions (Unit 7, Class 11)
• Classification of Elements and Periodicity in Properties (Unit 9, Class 11)
• The d- and f-Block Elements (Unit 11, Class 12)
• Biomolecules (Unit 19, Class 12)

Unit 20, Principles Related to Practical Chemistry, is tested through the experiments and tests listed in the syllabus and has no separate notes chapter.

How should you revise Chemistry for NEET and JEE Main 2027?

Read the NCERT chapter first, then use these notes to revise reactions and formulas and test yourself. NEET UG 2027 is expected in May 2027; dates are on the NEET UG 2027 page.

1. Read each chapter in the NCERT Class 11 or Class 12 Chemistry textbook, including the in-text and exercise questions.
2. Revise the key points above, then open the chapter notes page and the notes PDF.
3. Keep a separate list of named reactions, reagents and exceptions for Organic and Inorganic Chemistry, and revise it every week.
4. Solve the Chemistry questions on that chapter from NEET question papers and JEE Main previous year question papers.
5. Take timed tests on the NEET mock test and note every wrong answer.

For the other subjects, see the Physics notes for NEET and JEE Main and the NEET Biology notes.

Chemistry Notes for NEET and JEE Main 2027 FAQs