Friends, we see many colorful things around us.
If somebody asks you to categorize above materials you would probably say Pencil, eraser, chalk pieces are solids, Water, Ink, various colour juices are liquids and Inflated balloons, smoke of the incense sticks are in gaseous states.
These are called the states or phases of the matter.
Today we will learn more about the states of the matter.
To demonstrate this we will require – three 50 ml syringes with nozzles, chalk pieces, water, incense stick and match box.
Take a first syringe and fill it with some chalk pieces. The shape and size of chalk pieces will not change. Now close the nozzle of the syringe. If you press the piston of the syringe then the chalk pieces convert into small pieces and become powder. When you apply more force on this powder it will not further change its size and shape .This shows solid has fixed shape and size and it’s in compressible. The forces between chalk molecules are so strong to oppose its free movement. They only have a choice to vibrate.
Now take the second syringe close the nozzle and fill it with some liquid like water. The water will take the shape of the syringe but the volume of water will not change. Now fix the piston and remove the air bubble and close the outlet by using nozzle. Even if you press the piston of syringe very hard the volume of water will not change. This shows the liquids does not fixed shape and are little compressible. But, here it will not be noticed by muscle power.
Now take last syringe and close the nozzle and fill smoke using incense stick. Move the piston of syringe harder, you will see there is change in the volume of the gas. Gases neither have a definite shape nor does volume do this show they are very compressible.
What we learned in this activity, solids have regular and closely packed molecules and they not compressible.
In liquids the arrangement of molecules are loosely packed and with inter molecular spacing. They can flow easily and can take the shape of the container and are very little compressible.
The gas molecules move in all directions at faster speed with large inter spacing. So the attraction forces between the molecules are low and make gas easy to compress.

Team: Ashok Rupner, Apurva Barve, Shanti Pise, Prachi Pasalkar, Shilpa Jain

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