Board Exam Session 2026-27

Tamil Nadu Board Class 12 Science Important Chapters 2026-27

Key Topics & High-Weightage Chapters for TNBSE Class 12 Science Board Exams

Physics • Chemistry • Biology/Mathematics • Most Important Chapters • Board Exam Priority Topics

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4 Core Science Subjects High-Weightage Chapters Board Exam Focus JEE/NEET Priority

Important Chapters for Science Board Exams 2026-27

Focus on these high-priority chapters for effective board exam preparation and maximum scores. These chapters also form the core of JEE/NEET preparation.

Physics - Important Chapters

Unit	Important Topics	Priority
Electrostatics	Electric Charges and Fields - Coulomb's Law, Gauss's Law Electric Potential and Capacitance - Capacitors, Dielectrics Electric Dipole and its Applications	Very High
Current Electricity	Ohm's Law, Resistivity, Conductivity Kirchhoff's Laws and Applications Wheatstone Bridge and Meter Bridge Potentiometer and its Applications	Very High
Optics	Ray Optics - Reflection, Refraction, Lenses, Prism Wave Optics - Interference, Diffraction, Polarization Optical Instruments - Microscope, Telescope	High
Modern Physics	Photoelectric Effect - Dual Nature Atoms - Bohr Model, Atomic Spectra Nuclei - Radioactivity, Nuclear Reactions Semiconductor Electronics - Diodes, Transistors	High
Electromagnetic Induction	Faraday's Law, Lenz's Law Self and Mutual Induction AC Circuits - Series LCR Circuit Transformers and their Applications	Medium
Magnetic Effects	Biot-Savart Law, Ampere's Law Magnetic Field Due to Solenoid Force on a Moving Charge - Lorentz Force Magnetic Properties of Materials	Medium

JEE Focus: Electrostatics, Current Electricity, and Modern Physics are crucial for JEE Main and Advanced.

Chemistry - Important Chapters

Unit	Important Topics	Priority
Physical Chemistry	Solutions - Raoult's Law, Colligative Properties Electrochemistry - Nernst Equation, Electrochemical Cells Chemical Kinetics - Rate Laws, Order of Reaction Thermodynamics - Laws, Enthalpy, Entropy, Gibbs Free Energy	Very High
Organic Chemistry	Haloalkanes and Haloarenes - Properties, Reactions Alcohols, Phenols and Ethers - Preparation, Properties Aldehydes, Ketones and Carboxylic Acids - Reactions Amines - Classification, Properties, Reactions Biomolecules - Carbohydrates, Proteins, Nucleic Acids	Very High
Inorganic Chemistry	Coordination Compounds - Nomenclature, Isomerism d-Block and f-Block Elements - Transition Metals p-Block Elements - Group 15, 16, 17, 18 Qualitative Analysis - Identification of Ions	High
Environmental Chemistry	Environmental Pollution - Air, Water, Soil Green Chemistry - Principles and Applications Waste Management - Recycling, Biodegradation	Medium

JEE/NEET Focus: Physical Chemistry, Organic Chemistry, and Coordination Compounds are crucial for both JEE and NEET.

Biology - Important Chapters

Unit	Important Topics	Priority
Genetics & Evolution	Principles of Inheritance - Mendelian Genetics Molecular Basis of Inheritance - DNA, RNA, Replication Evolution - Origin of Life, Natural Selection Genetic Disorders and Genetic Engineering	Very High
Animal Physiology	Digestion and Absorption - Human Digestive System Breathing and Exchange of Gases - Respiratory System Body Fluids and Circulation - Blood, Heart Neural Control and Coordination - Nervous System Chemical Coordination - Endocrine System	Very High
Plant Physiology	Photosynthesis - Light Reaction, Calvin Cycle Respiration in Plants - Glycolysis, Kreb's Cycle Plant Growth and Development - Hormones Plant Transport - Water and Mineral Uptake	High
Ecology & Environment	Organisms and Populations - Abiotic and Biotic Factors Ecosystem - Structure, Function, Energy Flow Biodiversity and Conservation - Levels, Importance Environmental Issues - Pollution, Climate Change	Medium

NEET Focus: Genetics, Animal Physiology, and Plant Physiology are crucial for NEET. 90% questions come from NCERT.

Mathematics - Important Chapters

Unit	Important Topics	Priority
Calculus	Continuity and Differentiability - Concepts Application of Derivatives - Maxima/Minima Integrals - Indefinite and Definite Integration Application of Integrals - Area under Curves Differential Equations - Formation, Solution	Very High
Vectors and 3D Geometry	Vectors - Algebra, Dot and Cross Product Three Dimensional Geometry - Lines, Planes Linear Programming - Formulation, Graphical Method	High
Probability	Probability - Conditional, Bayes' Theorem Random Variables and Probability Distributions Mean and Variance of Probability Distributions	High
Relations and Functions	Relations and Functions - Types, Composition Inverse Trigonometric Functions - Properties Matrices and Determinants - Operations	Medium

JEE Focus: Calculus and Algebra are crucial for JEE Main and Advanced. Practice problems daily from these topics.

Board Exam Focus Areas

Physics Board Exam Focus

• Numerical Problems: Practice numerical problems from Electrostatics, Current Electricity, and Optics
• Derivations: Practice derivations of key formulas
• Conceptual Questions: Focus on conceptual understanding
• Diagram-based Questions: Practice diagrams of optical instruments and circuits
• Previous Year Papers: Solve last 5-10 years' board papers

Chemistry Board Exam Focus

• Reactions: Practice all organic reactions and mechanisms
• Equations: Practice balancing chemical equations
• Numericals: Practice numerical problems from Physical Chemistry
• Name Reactions: Memorize important name reactions
• Previous Year Papers: Solve last 5-10 years' board papers

Biology Board Exam Focus

• NCERT Focus: Thorough reading of NCERT textbooks
• Diagrams: Practice labeling all diagrams
• Practical-based Questions: Focus on practical experiments
• Application-based Questions: Practice application-based questions
• Previous Year Papers: Solve last 5-10 years' board papers

Mathematics Board Exam Focus

• Calculus: Master derivatives, integration, and applications
• Algebra: Practice matrices, determinants, and vectors
• Problems: Solve 20+ problems daily
• Step-by-step: Show complete steps in long answer questions
• Previous Year Papers: Solve last 5-10 years' board papers

How to Use This Chapter List for Board Exam Preparation

Prioritize High-Weightage Chapters

Focus first on chapters marked "Very High" and "High" priority. These chapters typically cover 60-70% of the exam marks.

Create Chapter-wise Timetable

Allocate more time to important chapters in your study schedule. Dedicate 2-3 days for "Very High" priority chapters.

Practice Previous Year Questions

Focus on questions from these chapters in previous board exams and competitive exams.

Multiple Revisions

Revise high-priority chapters multiple times before the board exam for better retention.

Success Strategy: Master the "Very High" priority chapters first. These chapters typically cover 60-70% of the exam marks. Once you're confident with these, move to "High" priority chapters. Finally, revise "Medium" priority chapters for completeness. For JEE/NEET, focus more time on "Very High" and "High" priority chapters.