1. Identify the materials that each objects are made of Toy, Tumbler, Bag, Lock and key .
Ans:
| Objects | Materials made up of | |
| Toy | plastic, wood, clay | |
| Tumbler | steel, glass, silver | |
| Bag | cloth, plastic, leather | |
| Lock and key | steel, aluminium, copper |
2. Identify the different type of objects that are made from the same materials. Leather, Plastics Cotton, Glass, Gold .
Ans:
| Materials | Objects made of these materials |
| Leather | shoes, bags, sofa, suitcase |
| Plastics | bags, chair, bottles, pipes |
| Cotton | clothes, bed sheet, ear buds, bandage |
| Glass | mirror, plate, cups, bowls |
| Gold | spoon, chairs, rings, bangles |
3. What are the properties of materials?
Ans : Properties of Materials are :
(i) Appearance (ii) Hardness (iii) Soluble or insoluble
(iv) Transparency (v) Objects may float or sink in water .
4. What kind of materials have lustre?
Ans: Materials like metals usually have lustre:
E.g. Iron, copper, aluminium and gold.
5. Which material is referred to as soft?
Ans: Materials which can be compressed or scratched easily are called soft.
6. Which material is referred to as hard?
Ans: Materials which are difficult to compress are called hard.
7. Mix the below substance in water and check what disappears, what doesn’t?
Sugar, Sand, Chalk powder, Sawdust, Flour, Baking powder .
Ans:
| Substance | Disappears/ does not disappear in water |
| Sugar | disappears in water. |
| Sand | does not disappear in water |
| Chalk powder | disappears in water. |
| Sawdust | does not disappear in water |
| Flour | disappears in water. |
| Baking powder | disappears in water. |
8. What are soluble substances?
Ans: A substance which completely disappears or dissolved in water is called soluble substance.
9. What are insoluble substance?
Ans: A substance which does not mix with water and do not disappear even after we stir for a long time is called insoluble substance.
10. What is transparent?
Ans: Substance or materials, through which things can be seen are called transparent.
11. What is Opaque?
Ans: There are some materials through which you are not able to see. These materials are called opaque.
12. What is translucent?
Ans: The materials through which objects can be seen, but not clearly , are known as translucent.