Properties of Materials

Class 6 Science · Chapter 6: Materials Around Us · NCERT Curiosity section 6.3

Learn

Appearance: some materials shine (lustrous), like gold, silver and a new steel spoon. Wood, cloth and paper do not shine. A metal that looks dull can be made shiny again by rubbing it with sandpaper.

Hard or soft: a material that is difficult to scratch or press, like iron or stone, is hard. One that is easy to press or scratch, like cotton, sponge or butter, is soft.

Light: materials you can see clearly through are transparent (clear glass, clean water). Those that let some light through, blurry, are translucent (butter paper, frosted glass). Those that let no light through are opaque (wood, metal, cardboard).

In water: sugar and salt dissolve (soluble); sand, chalk and oil do not (insoluble). Some objects float (wood, cork, plastic ball), others sink (stone, iron nail, coin).

Explore: test the materials yourself.

1. Shine the torch and group each object.
2. Now stir each one in water.

Remember

• Properties include shine, hardness, how light passes (transparent, translucent, opaque), dissolving and floating.
• Test, don't guess: try each property with a simple activity.

Quick check

Butter paper lets some light through but you cannot see clearly through it. It is …

1. translucent
2. transparent
3. opaque
4. lustrous

Think about it

Which material would you choose for a pencil box that lets you see the pencils inside but is hard to break? Why?

Practice

Practise with fresh questions at three levels (easy, medium, hard), some answered hands-on, with hints and worked answers. Get 4 of your last 5 right to finish the topic.