I. Tick (✓) the correct option.

1. 

Ans. Molecules

2.

Ans. Wood.

3.

Ans. Glass.

4. 

Ans. Water and coconut oil.

5. 

Ans. Solids and good conductors of heat.

6. 

Ans. Clear glass.

II. Answer the following questions in one sentence.

1.

Ans. Cotton.

2. 

Ans. Yes, gold is a lustrous material.

3. 

Ans. A leaf floats on water because it is lighter than water.

4.

Ans. Wood is an opaque material because it does not allow light to pass through it.

5. 

Ans. Liquids that do not dissolve in water are called immiscible liquids.

III. Answer the following questions in two sentences.

1.

Ans. The arrangement of molecules affect the state of matter. In a solid the molecules are closely packed while in a liquid the molecules are loosely packed and in gases molecules are far apart.

2. 

Ans. When a material dissolves in a liquid it forms a solution. Salt dissolves in water and forms a salt solution.

3.

Ans. Substances that dissolve in water are called soluble substances. Example salt, sugar.

Substances that do not dissolve in water are called insoluble substances. Example sand, flour.

4. 

Ans. If an object is lighter than water it floats and if it is heavier than water it sinks.

5. 

Ans. Transparent materials allow light to pass through them. On the other hand the translucent materials partially allow the light to pass through them. Besides we can see clearly through a transparent material but we cannot see clearly through a translucent material.

IV. Answer the following questions in four to five sentences.

1. 

Ans. When an incense stick is burnt the fragrance spreads in the whole room because the smoke coming out from the incense stick is a gas and all gases spread in the available room so quickly this is why we get the fragnance everywhere inside the room.

2.

Ans. Boats are made of wood because it is lighter than water and therefore it floats on water.

3. 

Ans. Glass is used to make electric bulbs because glass is a transparent material. And therefore light comes out from the bulbs and spreads light.

4.

Ans. We can distinguish whether a given material is transparent, translucent or opaque by looking through the material. If we can see clearly through the material then it is transparent and if we cannot see through the material then it is opaque and if we can see through the material but not clearly then it is translucent material.