Materials Required 

• Plastic syringe without needle  
• Beaker
• Water  
• Oil

The Procedure

Real Lab Procedure

• Hold the cylinder of a plastic syringe of maximum available size in one of your hands.  
• Insert the piston into the syringe cylinder and bring it to a certain level inside the syringe cylinder. In this situation air (gas) is inside the syringe.  
• Note and record the reading of the piston in the syringe, i.e., initial reading.
• Close the outlet nozzle of the syringe strongly by one of the fingers of the same hand holding the syringe cylinder.
• Apply a little force on the piston to push it in the syringe cylinder (that is to compress the air). 
• Keep on applying the force on the piston to push it further inside the syringe cylinder until it stops moving.
• Note and record the reading of the piston in the syringe cylinder i.e., the final reading.
• Take out the piston from the syringe and unplug the nozzle.  
• Fill the syringe with water.  
• Insert the piston into the syringe.  
• Slowly push it inside the cylinder to allow the air pass through the nozzle of the syringe. Ensure that there is no air bubble inside the cylinder.  
• Note the reading of the piston in the syringe i.e., initial reading for water. 
• Again, close the nozzle of the syringe strongly. 
• Apply force on the piston to push it in (or to compress the water inside).  
• Note and record the final reading.  
• Repeat the experiment with other liquids. Record observations. 

Simulator Procedure

• An Introductory note is shown; 

  “The term "compressibility" refers to the amount that a given volume of a substance, whether solid, liquid, or gas, decreases when subjected to pressure. The degree of compressibility depends upon the intermolecular spacing between the particles of a matter. The greater the space between the particles, the greater the possibility of the constituent particle being compressed after pressure is applied. The intermolecular spacing between gas particles is very large when compared to liquid particles because the particles in a gas molecule are loosely packed. Most of the volume of gas is composed of a large amount of empty space between the particles.”

• Click on the Next button.
• Select water from dropdown. 
• Click on the syringe to take it.
• Drag and drop the syringe towards the beaker containing water. 
• Click on the piston of the syringe. 
• Click on the piston to push. 
• Select Oil from dropdown. 
• Click on the syringe to take it. 
• Drag and drop the syringe towards the beaker containing oil. 
• Click on the piston of the syringe. 
• Click on the piston to push. 
• Select Air from dropdown. 
• Click on the syringe to take it. 
• Click on the piston of the syringe. 
• Click on the piston to push. 
• Click on the Inference icon: 

  “From the experiment, we can understand that although the gases have more degree of compressibility it does not mean that the liquids cannot be compressed. They can also be compressed, but a greater amount of pressure is required. The intermolecular space between gas particles is much larger than the intermolecular space between liquid particles. Hence, gases are more compressible, and liquids are not.”

Observation

We will notice that the syringe with air is much easier to insert than the syringe with water. 

Results and Discussion 

Infer from the observations that the gases are readily compressible while liquids are not. This shows that gases have more vacant space between the constituent particles.   

Precaution

• Use a piece of cloth to securely close or plug the syringe cylinder's nozzle. 
• Don’t use the syringe’s needle because it could harm. 
• The motion of piston inside the syringe must be tight. Otherwise, air (or liquid) may leak from the gas-piston boundary (or liquid-piston boundary).