NCERT Class 8 Science Curiosity (Sanskrit): Chapter 7 — अध्यायः ७ द्रव्याणां कणात्मिका प्रकृतिः
This chapter, 'The Particulate Nature of Matter' (द्रव्याणां कणात्मिका प्रकृतिः) from NCERT's Class 8 Science Curiosity textbook, explores the fundamental composition of matter. It begins by posing intriguing questions about why solids can be piled up while liquids cannot, how liquids take the shape of containers, and the nature of air. Through an activity involving chalk (सुधाखण्ड), students are guided to break it down into smaller and smaller pieces, eventually leading to a fine powder. This process demonstrates that even the smallest visible particle is still a part of the original chalk, highlighting that matter is composed of tiny particles. The chapter emphasizes that this is a physical change, not a chemical one, as the fundamental nature of the substance remains unaltered. It lays the groundwork for understanding the particulate nature of matter, crucial for further scientific concepts in CBSE curriculum.
Quick info
| Board | CBSE / NCERT |
|---|---|
| Class | Class 8 |
| Subject | Science |
| Book | Curiosity (Sanskrit) |
| Chapter | Chapter 7 — अध्यायः ७ द्रव्याणां कणात्मिका प्रकृतिः |
| Language | Sanskrit |
| PDF type | NCERT Textbook |
| Session | CBSE 2026 |
| Reading time | 2 minutes |
| Word count | 247 |
Learning outcomes
- Understand that matter is composed of tiny particles.
- Differentiate between physical and chemical changes.
- Relate everyday observations to the particulate nature of matter.
- Develop inquiry skills by asking questions about matter.
Vocabulary
| Word | Meaning |
|---|---|
| द्रव्य | Matter |
| कण | Particle |
| प्रकृति | Nature |
| सुधाखण्ड | Chalk |
| चूर्ण | Powder |
| भौतिक परिवर्तन | Physical change |
| रासायनिक परिवर्तन | Chemical change |
| सूक्ष्म | Microscopic/Tiny |
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Practice questions
- Why can we pile up sand but not water? Answer: Sand particles are fixed and can be piled up, while water particles are free to move and spread out.
- What is the difference between a physical change and a chemical change? Answer: In a physical change, the substance's form changes but not its chemical identity. In a chemical change, a new substance is formed.
- Is the process of grinding chalk into powder a physical or chemical change? Explain. Answer: It is a physical change because the chalk is broken into smaller particles, but it remains chalk. No new substance is formed.
Frequently asked questions
What is the main idea of Chapter 7 of NCERT Class 8 Science Curiosity?
The chapter explains that matter is composed of tiny particles and demonstrates this through activities like grinding chalk.
What activity is described in Chapter 7 to understand the nature of matter?
The chapter describes an activity where students break a piece of chalk into smaller and smaller pieces until it becomes a fine powder.
Is grinding chalk into powder a physical or chemical change?
Grinding chalk into powder is a physical change because the chemical composition of chalk does not change.
What questions does the chapter pose at the beginning?
It asks why solids can be piled but liquids cannot, how liquids take shape, and about the nature and origin of air.
What is the Sanskrit term for 'matter' used in the chapter?
The Sanskrit term for 'matter' used in the chapter is 'द्रव्य'.
Related resources
Important topics
Topics covered
NCERT Class 8 Science — Curiosity (Sanskrit) — Chapter 7 — अध्यायः ७ द्रव्याणां कणात्मिका प्रकृतिः. Verified by NCERT Help Editorial Team. Reviewed on 29 Jul 2026. Last updated 10 Aug 2026.