CBSE Class 10 Science Important Questions & Topics for Board Exam 2026

Science is one of the highest-scoring subjects in CBSE Class 10 if you prepare strategically. Here's a chapter-wise breakdown of important topics and question types based on previous year board papers (2020-2025).

Chemistry (Most Scoring Section)

Chemical Reactions and Equations (Chapter 1)

Balancing equations, types of reactions (combination, decomposition, displacement, double displacement, redox). At least one question on identifying reaction types appears every year.

Acids, Bases and Salts (Chapter 2)

pH scale, salt preparation, Plaster of Paris, baking soda. Practice the chemical formulas and reactions — 2-3 questions are guaranteed.

Carbon and its Compounds (Chapter 4)

Homologous series, IUPAC naming, properties of ethanol and ethanoic acid. Structural formulas and chemical properties carry 5 marks.

Physics (Practice Numericals)

Electricity (Chapter 12)

Ohm's law, series and parallel circuits, power and energy calculations. This chapter alone carries 8-10 marks. Practice circuit diagram numericals daily.

Light — Reflection and Refraction (Chapter 10)

Mirror formula, lens formula, ray diagrams. Learn sign conventions thoroughly — most students lose marks here due to sign errors.

Magnetic Effects of Electric Current (Chapter 13)

Fleming's rules, electromagnetic induction, AC vs DC. Drawing neat diagrams of motors and generators is important for full marks.

Biology (Focus on Diagrams)

Life Processes (Chapter 6)

Human digestive system, heart diagram, excretory system. Practice labeling diagrams — a 5-mark diagram question appears every year.

Control and Coordination (Chapter 7)

Nervous system, reflex arc, plant hormones. Differentiation questions (voluntary vs involuntary, cerebrum vs cerebellum) are common.

Heredity and Evolution (Chapter 9)

Mendel's laws, monohybrid and dihybrid crosses, sex determination. Practice Punnett square problems — they're guaranteed in the exam.

Preparation Strategy

1. Complete NCERT thoroughly — read every line, solve every question
2. Solve board papers from 2020-2025 to understand the pattern
3. Take mock tests to build speed and accuracy
4. Use flashcards for formulas, reactions, and definitions
5. Practice diagram drawing — neatness matters for full marks

Practice with CBSE Prepmaster

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