# CBSE Class 9 Science Chapter Wise Most Important Topics

By Renuka Miglani|Updated : February 24th, 2021

CBSE Class 9 Science Chapter Wise Topics - Are you searching for the most scoring and important topics for your upcoming CBSE Class 9 Science Exam 2021? Are you looking for chapter-wise highly weightage topics to prepare for your exam? Then, I must say you are at the right place. This article will help you to summarize the vast syllabus of Class 9 Science and prepare you for your upcoming Class 9 Exam.

BYJU'S Exam Prep brings here a collection of all the important topics and highly weightage topics from each chapter of Science for Class 9. With all these topics in one place you will find it easy to prepare all the chapters in a short period of time. This will also help you to summarise the vast syllabus of Class 9 for Science and help you to ace your upcoming Class 9 CBSE exam.

## Chapter Wise Important Topics for CBSE Class 9 Science

Certain topics from the following chapters are easy to learn and master. Therefore, practicing these topics before examination will lead to the best results.

### Physics:

1. Motion

Most questions from this chapter are numerical problems and can be tricky to solve, however the following topics usually have straightforward answers and therefore are really scoring.

• Average Speed and Average Velocity
• Distance and Displacement
• Uniform Circular Motion

2. Force and Laws of Motion

The following topics in this chapter are commonly asked and do not involve much calculation. Mastering these topics is easy.

• First Law of Motion
• Momentum
• Third Law of Motion

3. Gravitation and Floatation

The problems from this chapter can be quite tricky and difficult to solve. The following topics, however are easier and are asked frequently:

• Kepler’s First and Second Laws
• Density and Relative Density
• Thrust and Pressure

4. Work, Energy and Power

This chapter is one of the most scoring chapters among others, but even then there are certain topics which are very easy and frequently asked.

• Scientific concept of work
• Definition of Energy and its Unit
• Power and Its unit
• Kinetic Energy

5. Sound (Removed from revised syllabus of 2020-21)

The following topics from this chapter are easy to score and are interesting too. Therefore, mastering these topics would be beneficial to your exam preparation

• Human Ear
• Characteristics of sound
• Reverberation
• Echo
• Frequency, Time Period
• Velocity of Sound

### Chemistry:

1. Matter in Our Surrounding (Omitted chapter in 2020-21)

Matter and its properties, interconversion of states of matter, difference between evaporation and boiling, formula for conversion of 0C to K and vice versa

2. Is Matter Around Us Pure

Difference between physical and chemical change, pure substances, methods of separation or separation techniques, solution and types, concentration calculations (density and g/L strength), mixtures (suspensions and colloids)

3. Atoms and Molecule

Difference between- (i) atoms and molecules (ii) elements and compounds, ions , laws of chemical combination, dalton’s atomic theory - postulates and demerits, chemical symbols and formulas, concept of molecular mass, mole (numerical)

4. Structure of Atom

Fundamental particles, atomic models- Thomson, Rutherford, Bohr’s, Mass number and atomic number, isotopes and isobars, formula to calculate the average atomic mass

### Biology:

1. The Fundamental Unit of Life

• Structure and Function of Cell Organelles
• Osmosis, Diffusion, Plasmolysis

2. Tissue

• Function of Xylem, Phloem and Complex Permanent Tissues
• Protective Animal Tissues
• Connective Tissues

3. Why do we fall ill

• Communicable and Non-Communicable Diseases
•  Vaccination

4. Natural Resources

• Biogeochemical Cycles - Oxygen, Carbon and Nitrogen
• Air , water and soil pollution