Class 8 Science Chapter 7 – Particulate Nature of Matter PPT
This
84-slide illustrated PowerPoint presentation covers
Class 8 Science Chapter 7: Particulate Nature of Matter from the new NCERT textbook
Curiosity (Session 2026-27). Prepared by Sumeet Sahu, Unique Study Point, Indore — 100% free, no login required.
What Is This Chapter About?
Chapter 7 of Class 8 Science (Curiosity) introduces one of the most important ideas in science — that all matter around us is made of tiny, invisible particles called
constituent particles. These particles have spaces between them, attract each other, and are always in motion. The chapter explains why sugar dissolves in water, why perfume spreads across a room, and why solids, liquids, and gases behave differently.
Chapter Index Covered in This PPT
- Section 7.1 – What Is Matter Composed of?
- Section 7.2 – What Decides Different States of Matter?
- Section 7.3 – How Does the Interparticle Spacing Differ in the Three States?
- Section 7.4 – How Particles Move in Different States of Matter?
- Exercises and Revision – All NCERT exercise questions with answers (Q1 to Q9)
Section 7.1 – What Is Matter Composed of? (Slides 1–18)
This section builds the foundational idea that matter is made of particles that are too small to see. Key topics covered:
- What matter is made of — constituent particles (atoms and molecules)
- Why particles are extremely small — they cannot be seen even under an ordinary microscope
- Interparticle spaces — when sugar dissolves in water, its particles occupy the spaces between water particles
- Why unstirred sugar-water is not sweet at the top but sweet throughout when stirred
- Salt dissolving in ocean water — salt is present but unseen
- Chalk powder activity — every speck of chalk is still composed of the same chalk particles
- Interparticle forces of attraction — particles attract each other
- Evidence that matter is particulate: dissolving, diffusion, compressibility
Section 7.2 – What Decides Different States of Matter? (Slides 19–36)
This section explains why the same substance can be a solid, liquid, or gas depending on how tightly its particles are held. Key topics:
- Interparticle forces of attraction decide the state of matter
- Thermal energy (heat energy) — how adding heat increases particle vibration
- Solid state — particles closely packed, definite shape, definite volume, cannot be compressed
- Liquid state — particles loosely packed, no fixed shape, definite volume, slightly compressible
- Gaseous state — particles far apart, no fixed shape, no fixed volume, highly compressible
- Melting point — the temperature at which a solid melts into a liquid
- Boiling point — the temperature at which a liquid converts to gas
- How does a solid melt? — heat increases thermal energy until interparticle forces can no longer hold particles
- Properties comparison table: Solid vs Liquid vs Gas
Section 7.3 – Interparticle Spacing in the Three States (Slides 37–52)
This section uses 3D visual models to compare how particles are arranged in solids, liquids, and gases. Key topics:
- Solid: particles closely packed, minimum interparticle spacing, ordered arrangement
- Liquid: particles a little loosely packed, slightly more interparticle spacing, random but close arrangement
- Gas: particles far apart, maximum interparticle spacing, completely random arrangement
- Important NCERT fact: gaps between particles in solids are NOT filled with air — they contain nothing at all
- Why solids are incompressible — no room to compress
- Why gases are highly compressible — large interparticle spaces
- Interparticle spacing comparison across all three states
Section 7.4 – How Particles Move in Different States (Slides 53–59)
This section explains particle motion (kinetic energy) in each state. Key topics:
- Particles in solids — vibrate about fixed positions, do not move freely
- Particles in liquids — vibrate and slide over each other, move freely within the liquid
- Particles in gases — move rapidly in all directions, fill any container completely
- Diffusion — spontaneous spreading of particles from high to low concentration
- Diffusion in gases — perfume / incense spreading across a room
- Diffusion in liquids — ink dropping into water
- Diffusion is faster in gases than in liquids
- Effect of temperature on diffusion — faster at higher temperatures
NCERT Exercise Questions with Answers (Slides 57–83)
All NCERT Curiosity Chapter 7 exercise questions are covered with detailed answers and 3D visual explanations:
- Exercise Q1 – Is chalk powder still composed of the same substance on grinding?
- Exercise Q2 – True or false statements about melting, states, interparticle attractions, and camphor
- Exercise Q3 – Why do solid, liquid, and gas have different properties?
- Exercise Q4 – Why do gases fill the entire available space?
- Exercise Q5 – Arrange in order of increasing interparticle spacing
- Exercise Q6 – Why is it easier to compress gases than liquids?
- Exercise Q7 – What happens to particles when ice is heated?
- Exercise Q8 – Why does camphor fragrance fill the entire room?
- Exercise Q9 – Why can salt not be seen when dissolved in water?
Key Concepts Covered
- Constituent particles — atoms and molecules that make up matter
- Interparticle spaces — gaps between particles in all states of matter
- Interparticle forces of attraction — the forces that hold particles together
- Thermal energy — heat energy that causes particles to vibrate and move
- Melting point and boiling point
- Diffusion — definition and real-life examples
- Compressibility — why gases compress easily, solids do not
- States of matter — solid, liquid, gas — properties comparison
PPT Features
- 84 slides, fully aligned with NCERT Curiosity 2026-27 new syllabus
- Hyperrealistic 3D illustrated visuals — every concept shown as a clear 3D model
- Exam Focus slides — important points marked for school examinations
- NCERT exercise questions and answers included
- USP double-border design — easy to project in classroom
- Prepared by Sumeet Sahu, experienced CBSE teacher, Unique Study Point, Indore
- 100% free — no login, no hidden charges
Frequently Asked Questions
What is the particulate nature of matter?
The particulate nature of matter means that all matter — solids, liquids, and gases — is made up of tiny particles (atoms or molecules) that are too small to see with the naked eye. These particles have spaces between them (interparticle spaces), attract each other (interparticle forces), and are always in motion.
What is diffusion in Class 8 Science Chapter 7?
Diffusion is the spontaneous spreading of particles from a region of high concentration to a region of low concentration. Example: the smell of perfume or incense spreading across a room is diffusion of gas particles. Diffusion is faster in gases than in liquids and faster at higher temperatures.
What are interparticle spaces?
Interparticle spaces are the gaps between the constituent particles of matter. In solids, interparticle spaces are very small. In liquids, they are slightly larger. In gases, interparticle spaces are very large, which is why gases can be compressed and can fill any container.
What is the difference between melting point and boiling point?
The melting point is the temperature at which a solid converts into a liquid. The boiling point is the temperature at which a liquid converts into a gas. Both depend on how strong the interparticle forces of attraction are in that substance.
Why can gases be compressed but solids cannot?
Gases can be compressed because they have very large interparticle spaces — the particles can be pushed closer together. Solids cannot be compressed easily because their particles are already closely packed with very little interparticle space left.
Also Study – Chapter 7 Complete Package
For complete preparation of Class 8 Science Chapter 7 Particulate Nature of Matter, use both resources together:
About Unique Study Point
Unique Study Point (USP) is a free CBSE study materials coaching institute based in Amitesh Nagar, Indore, Madhya Pradesh. We provide free PPTs, notes, worksheets, and practice papers for Classes 6 to 10, fully aligned with the new NCERT 2026-27 syllabus. All materials are prepared by Sumeet Sahu, an experienced CBSE teacher. Download our app from the Google Play Store or visit www.uniquestudyonline.com. For coaching admissions, call 8103405051.