Chapter-4 Sorting material into Groups.

1. Material: All objects we are made of one or more material.

2. Shorting material: This material may be glass, metal, plastics, wood, paper, mud, or soil.

3. Usually metals: materials that have luster are usually metal.

4. Soluble material: salt and sugar are soluble material.

5. Insoluble material: Iron fills and stores are insoluble material.

6. Different types of materials: different types of materials have different properties.

7. Material is grouped:  Material is grouped together in the basis of similarities and differences in their properties.

8. Material grouped together: Thing are grouped together for convenience and so study ther properties.

9. Floating on water: There are many things are floating on the water are following:  

(1) Balloon

(2) Dry leaf

(3) Ball

(4) Dry wood

(5) Oil and etc

10. Examples of metals: Iron, aluminum and copper.

11. Soft material: Material which can be compressed or scratched easily are called soft material. Like cotton and sponge.

12. Hard material: Some other materials which are difficult to compress are called hard material. Like copper and iron.

13. Soluble material: Some substances have completely Disappeared are dissolved in water. These substances called soluble material. Like salt and sugar.

14. Insoluble substances: Some substances do not mix with water and disappear even after we stir for a long time. These substances are called insoluble substances. Like iron fills, stones, rubber etc.

15. Sink in water: There are many things are sink in water are following:

(1) keys 

(2) Stones

(3) Rod

(4) Bricks

(5) Glass and etc

16. Transparent objects: Some material through which things can be seen. These are called transparent material. Like glass, water, air and plastics.

17. Translucent objects: The material through which objects can be seen, but not clearly, are known as translucent objects. Like oily paper, polythene, oil and fiber sheet.

18. Opaque object: some material through which you are able to see. These materials are called opaque object. Like wood, cardboard and paper.