Chemistry Important Concepts, Formulae & Laws (CBSE, IGCSE, IB, JEE, NEET)

Quick Revision for School Boards (CBSE/ICSE/IGCSE/IB), NEET, JEE & Olympiads – By Hodu Academy
Your shortcut to Chemistry excellence! Here’s your all-in-one list for crucial Chemistry concepts, definitions, formulas, laws and results – handpicked by Hodu Academy’s Chemistry team.
Perfect for last-minute revision, board exams (CBSE/ICSE/IGCSE/IB), NEET/JEE aspirants, and Olympiad winners. Every topic is mapped for fast learning and exam scoring.

Bookmark this page as your Chemistry cheat-sheet—latest for 2025, and 100% relevant for IGCSE, IB & other international boards!
This page covers:
  • 250+ Key Chemistry concepts, definitions & reactions (IGCSE & IB compatible)
  • All important formulas, equations and short explanations
  • Laws, principles, SI units & constants in Chemistry
  • Quick clarifications for tough Chemistry terms
  • Practice links, detailed notes and rapid revision

Why Use This Chemistry Cheat Sheet?

Chemistry is the link between Physics, Biology, and the material world. A high score in Chemistry matters for NEET, JEE, Olympiads, CBSE, ICSE, IGCSE, IB and more. But Chemistry has hundreds of formulas, reactions, structures and tricky laws – making last-minute revision a headache.

This page helps you:
  • Revise hundreds of definitions, equations, trends and reactions in minutes
  • Find every important formula or chemical law for direct application
  • Look up names, periodic trends, laws, or organic reactions instantly
  • Zero in on what’s actually asked in boards & competitive exams
  • Be ready for IGCSE, IB & NEET Chemistry questions

Tip: Boost recall with Chemistry MCQ quizzes and reaction flashcards!

Complete Chemistry Important Concepts, Formulas & Laws List

250+ must-know Chemistry topics for Boards & Competitive Exams (including IGCSE & IB)
Categories covered: Atomic Structure, Periodic Table, Physical Chemistry, Chemical Reactions, Organic Chemistry, Inorganic Chemistry, Environmental, Industrial, Everyday Chemistry & more!
Mapped to: CBSE, ICSE, IGCSE, IB Diploma, NEET, JEE & Olympiads
118 Elements and Their Symbols and Atomic Numbers Acetone Acid And Base Difference Acids Bases and Salts Actinides
Addition Reaction Adsorption Chromatography Aldol Condensation Alkali Metals Ammonium Chloride
Applications of Redox Reactions Argon Arrhenius Equation Rate Constant And Temperature Atomic Number Mass Number Aufbau Principle
Aufbau Principle, Paulis Exclusion Principle and Hands Rule Bakelite: Structure and Uses Benzene Reactions Benzoic Acid - Structure and Properties Biodegradable and Non Biodegradable
Calcium Oxide Cathode Ray Experiment Charles Law Chemical And Its Composition Chemical Formula of Common Compounds
Classification Of Carbohydrates and Its Structure Classification of Organic Compounds Coefficient of Viscosity - Definition, Formula and Example Colligative Properties beRelative Lowering of Vapour Pressure Colloidal Solution
Components of Air Condensation Conformation Cracking Meaning Crystallization
Decantation Decomposition Reaction Dehydration of Alcohols Difference Between Alkali and Base Difference Between Atom And Ion
Difference Between Atom and Molecule Difference Between CNG and LPG Difference between Compound and Mixture Difference Between Element And Compound Difference Between Exothermic and Endothermic Reactions
Difference Between Mixture and Solution Difference Between Molecule and Compounds Difference Between Organic And Inorganic Compounds Difference between Physical and Chemical Change Difference between Vapor and Gas
Disaccharides Discovery of Protons and Neutrons Distillation Effects of Burning Fossil Fuels Electromeric Effect
Electron Configuration Electronic Configuration of First 30 Elements Electronic Configuration of Iron Electroplating Process Endothermic Reaction
Enthalpy Change Enzyme Catalysis Ester Ester Hydrolysis Ethanoic Acid
Exothermic Reaction Filtration Fuel Types Functions of Nucleic Acids Glycerin
Glycine Structure Glycogen Gravimetric Analysis Group 17 Trends Properties Heat Capacity Cp Cv Relation
Heavy Water Homogeneous Mixture and Heterogeneous Mixture Hunds Rule Hybridization Hydrochloric Acid
Hydrogen Peroxide Introduction: Importance of Forest IR Spectroscopy Iron Krypton
Lewis Dot Structures Metallic Bonds Metals and Nonmetals Methanol Mineral Resources
Mixtures Modern Periodic Table and Its Significance Mole Concept Monosaccharides NaHCO3
Natural Polymers Neutralization Reaction Non Metals Oxalic Acid Oxygen
Periodic Table Elements Periodic Trends in Properties of Elements Pesticides Phenol Preparation Phosphoric Acid
Physical and Chemical Properties of Carbon Physical And Chemical Properties of Water Physical Change and Chemical Change Polarity Polymers Uses
Polyvinyl Alcohol Positron Potassium Potassium Dichromate - Formula, Properties and Uses Potassium Permanganate
Precipitation Reaction Preparation of Benzene Preparation Properties and uses of Sodium Chloride Properties of Boron Family Properties of Solution
Redox Titration Relation Between Normality And Molarity Rusting Iron Prevention Rutherford Atomic Model Rutherford Atomic Model
Shapes of Molecules Vsepr Theory Shapes of Orbitals Sieving SilkWorm - Life Cycle of Silkworm, Diagram Silver Nitrate
Soaps And Detergents Sodium Hydroxide Structure of Benzene Sublimation Synthetic Fibres And Natural Fibres
Synthetic Polymers Tollens Test Toluene Transition Metals Tyndall Effect
Types of Organic Reactions Types of Solutions Types of Titration - Acid Base Titration Unsaturated Solutions Ununoctium
Ununpentium Uses of Acetone Uses of Air Uses of Bauxite Uses of Carboxylic Acid
Uses of Coal Uses of Ethers Health In Care Industry Uses of Formaldehyde Uses of Graphite Uses of Methanol and Ethanol
Uses of Minerals Uses Of Nitric Acid Uses of Phenol Uses of Propanol Uses of Sulfuric Acid
Uses of Water Valence Bond Theory Volumetric Analysis Waste Water Cycle Process
What is Dipole Moment? What is Eutrophication? What is Metallurgy? Wurtz Reaction Mohr’s Salt Titration with KMnO4
Gattermann Reaction Benzene Brown Ring Test Calcium Carbonate Cotton and its Various Uses
Difference between Petrol and Diesel Engine Difference between Sigma and Pi Bond Element-Manganese (Mn) Friedel Crafts Reaction Hofmann Elimination
Isomerism Laws of Chemical Combination Mannich Reaction Methods of separation Molisch’s Test
Name Reactions NMR Spectroscopy Non – Aqueous Titration Ozonolysis Mechanism – Ozonolysis of Alkenes and Alkynes Periodic Classification of Elements
Pinacol Pinacolone Rearrangement Planck’s Quantum Theory Pseudo First Order Reaction Rosenmund Reduction Mechanism Salt Analysis
Saponification Science in Everyday life and Its Importance Sericulture: Rearing of Silkworm to Produce Silk Spectrophotometer Principle Zone Refining
Reactivity Series Difference between isotropic and anisotropic Introduction to p-Block elements Plant fibres Inert Gases: Uses
Benzoin Condensation Difference between primary cell and secondary cell Partition Chromatography Applications of colloids Displacement Reactions
Handpicking Biogas: Uses of Biogas Acid Rain Types of Chemical Reactions SN2 Reaction Mechanism
Complexometric Titration markovnikov rule Kohlrausch Law Electrode Valency Chart
Order of Reaction Band Theory Difference Between Rusting and Corrosion Potentiometric Titration Frenkel Defect
Deforestation Stephen Reaction Mechanism Gattermann – Koch Reaction Mechanism Electronegativity Industrial Waste: Types
Ethylene Charge to Mass Ratio of an Electron Fehling Solution Photochemical Reactions Difference Between Endpoint and Equivalence Point
Second Order Reaction Etard Reaction Forms of water Preparation of Acetanilide Metallic Minerals and Non-Metallic Minerals
Ferric Chloride Henry's Law Preparation of Mohr's salt Schottky Defect Claisen rearrangement
Calcium sulphate Sodium carbonate Rubber Ethyl acetate Conductometric Titration
Resorcinol Difference Between Evaporation and Condensation States of Matter Boric Acid Types of Minerals
Finkelstein Reaction Electronegativity Chart Difference between Solid, Liquid and Gas in tabular form Aromaticity Drawbacks of Rutherford's Atomic Model
Thermosetting Polymers Preparation of Alkanes Examples of Bases Suzuki Coupling Reaction Standard Electrode Potential
Disadvantages of Plastics Reducing Agent Van't Hoff Factor Hard Water and Soft Water Organometallic compounds
Gay Lussac's Law Slaked Lime Borax Tetravalency of Carbon Boyle's Law
Ellingham Diagram Crystal Defects : Point Defects HVZ Reaction (Hell-Volhard-Zelinsky Reaction) Classification of Drugs Preparation of Sulfuric Acid
Lucas test Xenon Difluoride Bravais Lattice Classification of Oxides Elimination Reaction
preparation of polythene, Teflon and polyacrylonitrile Difference between cations and anions Uses of Limestone Fructose Azeotropes
Lewis Acid and Base Emulsification Dielectric properties of solids Zwitterion Birch Reduction Mechanism
Oxidation and Reduction Electrophilic Substitution Reaction Suspensions Aromatic Compounds Ores and Minerals
Adsorption theory of heterogeneous catalysis Wittig Reaction Difference between evaporation and boiling Intensive And Extensive Properties Of Matter Electronic Configuration of Group 16 Elements
Difference Between Elements and Atoms Sodium Oxide Gypsum Difference Between Alloy and Composite Chemical Equations
Thorium Lead Acid Battery Isotopes of Hydrogen Significant Figure Rules Electrophilic Addition Reactions Of Alkenes
Isothermal Expansion of an Ideal Gas Potassium Chloride - KCl Aluminum Oxide Difference Between Acetic Acid and Glacial Acetic Acid Difference Between Polar and Nonpolar
Difference Between Baking Powder and Baking Soda Test for Phenolic group To prepare colloidal solution of starch Uses of Mica Pi Bonds
Potassium Chlorate Schmidt Reaction High density Polyethylene Huckel's Rule Discovery of Proton
Aluminium Ore: Extraction of Aluminium Benzene Hexachloride Caustic Potash or Potasium Hydroxide Electromagnetic Radiation - Wave Nature Atomic Number and Mass Number, Isotopes and Isobars
Preparation of Potash Alum Beckmann Rearrangement Heterogeneous Equilibrium Butane Factors Affecting Electrolytic Conductance
Scandium Homogeneous Equilibrium Phenols Nomenclcature Galvanic Corrosion Chlorine Trifluoride
Robinson Annulation Copper Pyridine Silver Carbonate Harmful Effects of Radiation

Chemistry Must-Know Laws, Principles & Constants

Important Laws & Principles:
  • Periodic Law, Mendeleev’s & Modern Periodic Law, Avogadro’s Law
  • Law of Conservation of Mass, Law of Definite Proportions, Law of Multiple Proportions
  • Boyle’s Law, Charles’ Law, Gay-Lussac’s Law, Henry’s Law, Raoult’s Law
  • Arrhenius, Bronsted-Lowry & Lewis Acid-Base Theory
  • Colligative Properties, Nernst Equation, Faraday’s Laws of Electrolysis
  • Le Chatelier’s Principle, Hess’s Law, Dalton’s Law of Partial Pressures
  • Principle of Limiting Reactant, van’t Hoff Factor, Kohlrausch’s Law
  • Aufbau Principle, Hund’s Rule, Pauli Exclusion Principle, Heisenberg Uncertainty Principle

Physical Constants:
  • Avogadro’s Number (NA) = 6.022 × 1023 mol-1
  • Gas Constant (R) = 8.314 J/mol·K
  • Faraday’s Constant (F) = 96500 C/mol
  • Boltzmann Constant (k) = 1.38 × 10-23 J/K
  • Speed of light (c) = 3 × 108 m/s
  • Planck’s constant heart = 6.626 × 10-34 Js

Tips to Score 90+ in Chemistry

  • Memorize all formulas, laws and reactions (use this table for daily revision!)
  • Practice MCQs, mechanisms and numerical problems for every chapter
  • Review definitions, periodic trends, and chemical names often
  • Create quick reaction maps and property tables for organic and inorganic topics
  • Use Hodu Academy’s Chemistry quizzes for rapid practice
For PDF downloads, practice sheets, or doubts, Contact Hodu Academy now!
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Last modified: Friday, 11 July 2025, 7:42 PM