Properties of Materials

Question 1:

How Will You Separate Solids (Dirt or Salt) From the Liquid (Water)?

Answer:

The following methods can be used to separate dirt or salt from water:

• Salt can be separated from water by the process of evaporation.
• Dirt can be separated by the process of sedimentation (settling of dirt particles at the base of the container) and decantation.
• Alum can be mixed with water to increase the rate of sedimentation and separate clear water.

 

Question 2:

Glass Is Fragile but Still Used to Make Windows on a Large Scale. Why Do You Think So?

Answer:

Glass is used to make windows due to following reasons:

• It is cheaper than other materials.
• It is transparent and allows light to pass through it.
• It is convenient to clean the glass.

 

Question 3:

Switches in the Electric Boards Are Made of Plastic Instead of Wood. Why?