Particulate Nature of Matter Class 8 Notes

Particulate Nature of Matter Class 8 Notes

Particulate Nature of Matter Class 8 Notes

1. Particulate nature of matter: All matter is made up of tiny particles, which can be atoms or molecules.
2. Interparticle spacing: The distance between particles in a substance.
3. Interparticle attractions: The forces that hold particles together within a substance.
4. Eventually: In the end, especially after a lot of delays.
5. Specks: A small spot, a very small amount.
6. Incense stick: A thin stick often made of bamboo, coated in aromatic materials that releases a sweet-smelling fragrance when burned (Agarbatti).
7. Plunger: Piston.
8. Dissolution: The process of a substance dissolving in a liquid to form a solution.
9. Spatula: A broad, flat, strip used to mix, spread and lift material.
10. Streaks: A long, thin mark of a different colour or substance.
11. Constituent particles: The basic building blocks of matter, which can be atoms, molecules, or ions.
12. Suspended particulate matter (SPM): The tiny particles, such as dust or smoke, that are suspended in the air.
13. Boiling point: The temperature at which a liquid turn into vapour at atmospheric pressure.
14. Evaporation: A process where liquid particles escape into the gas phase.
15. Gaseous state: The state of matter where particles are far apart and move freely.
16. Incompressible: When the particles are already closely packed and the volume does not change significantly under pressure.
17. Vapour formation: The process by which particles transition from the liquid state to the gaseous state.
18. Potassium permanganate: A chemical compound often used in experiments to demonstrate diffusion in liquids.

1. Matter

1. Definition: Anything that has mass and occupies. space.
2. Composed of particles (atoms and molecules).

2. States of Matter

Solid

1. Particles are closely packed.
2. Strong interparticle forces.
3. Fixed shape and volume.
4. Limited movement (vibrational).

Liquid

1. Particles are close but can move past each other.
2. Moderate interparticle forces.
3. Fixed volume but takes the shape of the container.
4. More freedom of movement compared to solids.

Gas

1. Particles are far apart.
2. Weak interparticle forces.
3. No fixed shape or volume; fills the entire container.
4. High kinetic energy and constant movement.

3. Interparticle Forces

1. Attractive forces that hold particles together.
2. Strength determines the state of matter.
3. Increased distance reduces the strength of these forces.

4. Interparticle Spacing

1. Exists in all states of matter.
2. Space between particles is not empty; it is often referred to as interparticle spaces.
3. Example: Sugar dissolving in water occupies spaces between water molecules.

5. Movement of Particles

1. In Solids: Limited to vibrational motion.
2. In Liquids: Particles slide past each other.
3. In Gases: High-speed movement; can spread and fill available space.
4. Example: Fragrance from an incense stick spreading in a room.

6. Real-Life Applications

1. Dissolving: Sugar in water, where sugar particles occupy spaces between water particles.
2. Cleaning: Soap molecules surround oil particles to lift stains.
3. Air Pollution: Suspended particulate matter (SPM) refers to tiny dust particles in the air.

7. Historical Context

1. Concept of particles dates back to ancient philosophers.
2. Acharya Kanad introduced the idea of Parmanu (atom) as the smallest indivisible particle.