MATTER IN OUR SURROUNDINGS LESSON 1


🌟 QUICK REVISION NOTES (VERY EASY LANGUAGE)

📘 Based on your NCERT chapter

🔹 1. Matter

  • Anything that has mass and occupies space is matter

  • Examples: air, water, chair

🔹 2. Particles of Matter

✔ Matter is made of tiny particles
✔ These particles:

  • are very small

  • have space between them

  • are continuously moving

  • attract each other


🔹 3. States of Matter

Property  Solid                LiquidGas
Shape           Fixed       No fixed shapeNo fixed shape
Volume           Fixed     FixedNot fixed
Movement       Very slow           MediumVery fast
Space        Very less     ModerateVery large

🔹 4. Change of State

  • By temperature (heating/cooling)

  • By pressure

Examples:


  • Ice → Water → Steam

🔹 5. Evaporation

  • Change of liquid → gas without boiling

  • Causes cooling

Factors affecting evaporation:

  • Temperature ↑ → evaporation ↑

  • Surface area ↑ → evaporation ↑

  • Wind speed ↑ → evaporation ↑

  • Humidity ↑ → evaporation ↓

📝 COMPLETE WORKSHEET (WITH ANSWERS)

✏️ SECTION A: VERY SHORT ANSWERS

Q1. Which of the following are matter?

✔ Chair ✔ Air ✔ Almonds ✔ Lemon water ✔ Smell of perfume

❌ Not matter: love, hate, thought, cold

👉 Reason: They do not have mass or occupy space

Q2. Why does hot food smell reach farther?

👉 Because:

  • Particles move faster at higher temperature

  • Diffusion increases

Q3. Diver cutting through water shows which property?

👉 Particles of matter have space between them

Q4. Characteristics of particles of matter

✔ Very small
✔ Have space
✔ Move continuously
✔ Attract each other

✏️ SECTION B: STATES OF MATTER

Q1. Increasing order of density

👉 air < exhaust < cotton < water < honey < chalk < iron

Q2. Differences between states

Property                  Solid            Liquid               Gas
Rigidity          Yes              No             No
Compressibility            Very low            Low            High
Fluidity                       No              Yes            Yes
Density                 High              Medium             Low

Q3. Give reasons

(a) Gas fills vessel

👉 Particles move freely in all directions

(b) Gas exerts pressure

👉 Particles collide with container walls

(c) Wooden table is solid

👉 Fixed shape + strong forces

(d) Hand moves in air but not wood

👉 Air has large spaces, wood has tightly packed particles

Q4. Why does ice float?

👉 Ice is less dense than water due to open structure

✏️ SECTION C: CHANGE OF STATE

Q1. Convert Kelvin to Celsius

a) 300 K = 27°C
b) 573 K = 300°C

Q2. State of water

a) 250°C → Gas (steam)
b) 100°C → Liquid + Gas (boiling point)

Q3. Why temperature remains constant?

👉 Heat is used as latent heat to change state

Q4. How to liquefy gases?

👉 By:

  • Increasing pressure

  • Decreasing temperature

✏️ SECTION D: EVAPORATION

Q1. Desert cooler works better on hot dry day

👉 Because:

  • High temperature → faster evaporation

  • Low humidity → more evaporation

Q2. Why matka water becomes cool?

👉 Due to evaporation through pores

Q3. Why palm feels cold with perfume?

👉 Evaporation absorbs heat → cooling effect

Q4. Why tea cools faster in saucer?

👉 Larger surface area → faster evaporation

Q5. Clothes in summer

👉 Cotton clothes
✔ Absorb sweat
✔ Help evaporation

🧠 EXTRA PRACTICE (MCQs)

  1. Matter is made of:

    • a) Cells

    • b) Particles ✅

    • c) Molecules only

  2. Maximum force of attraction:

    • a) Gas

    • b) Liquid

    • c) Solid ✅

  3. Evaporation causes:

    • a) Heating

    • b) Cooling ✅

    • c) Freezing

🔥 HOTS QUESTIONS (IMPORTANT)

Q1. Why do we smell perfume instantly?

👉 Gas particles diffuse quickly due to high speed

Q2. Why is steam more dangerous than boiling water?

👉 Steam has extra latent heat → more burns

Q3. Why are gases compressible?

👉 Large spaces between particles

Matter in Our Surroundings Worksheet

Name: ____________ Class: ____________ Date: ____________

Section A

1. Tick the correct options: Chair, Love, Air, Thought, Lemon water

2. Why does smell of hot food travel faster?

3. What property allows a diver to move in water?

Section B

4. Write characteristics of particles of matter.

5. Arrange in increasing density: air, water, iron, cotton

Section C

6. Convert: 300K to Celsius

7. State of water at 100°C

Section D

8. Why does evaporation cause cooling?

9. Why do we wear cotton clothes in summer?





Fun Activities for Class 3/4
Fun Activities

1. Smell Test: Compare hot vs cold food smell.
2. Diffusion Activity: Add ink in water and observe.
3. Evaporation Game: Wet cloth vs folded cloth drying.
4. Particle Game: Students act as solid, liquid, gas.



Revision Mind Map



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