Hey,

The chapters that are their in the syllabus are -

• Crop production and management
• Microorganisms : friend and foe
• Synthetic fibres and plastics
• Materials : metals or non metals
• Coal and petroleum
• Combustion and flame
• Conservation of plants and animals
• Cell - structure and functions
• Reproduction in animals
• Reaching the age of adolescence
• Force and pressure
• Friction
• Sound
• Chemical effects of electric current
• Some natural phenomenon
• Light
• Stars and the solar system
• Pollution of air and water

Also you can go through the NCERT class 8 science syllabus chapter wise mentioned in the link - https://school.careers360.com/ncert/ncert-syllabus-for-class-8-science

In this link you may find the chapter number, chapter name, and the topics that you have to study from the respective chapter.

Hope this might help you.