Boyle’s Law Demo

Physics II

March 2005

 

Robert Boyle was the first to publish the relationship between pressure and volume for a constant amount of gas held at a constant temperature.

 

This relationship if often stated as P ~ 1/V or PV = constant.  The ideal gas law gives this constant as nRT where n is the number of moles, T temperature in Kelvin, and R is the universal gas constant 8.315 J/(mol K).

 

Equipment:

          Vernier LabPro

          Vernier LabPro power supply

          USB cable to cable LabPro to PC

          Vernier Pressure Sensor PS-DIN with DIN-BTA adapter

                   (NOTE:  DO NOT use Biology Gas sensor BGP-DIN)

          20 cc syringe

          LoggerPro Software installed on PC

          BoylesLaw.MLB experiment file  http://members.cox.net/gilvick

 

This demo is run using the Logger Pro software package.  Open the experiment BoylesLaw found on the physics web page above. 

 

Run 4 separate demos with initial conditions of 20, 15, 10, & 5 cm taking data at 20, 15, 10, & 5 cm.

 

Using the ‘Data’ tab ‘Store Latest Run’ and ‘Rename Run’ to reflect the starting volume of each run.

 

Using the ‘Data’ tab sort on volume.

 

 

Consider:

          Compute n for the air in the syringe for each run.

          Run the logger P analysis “inverse” and comment on the constant WRT the calculated PV.

          Would this experiment work the same way with a larger syringe?

          The 20 cc syringe has a diameter of 2 cm.  Could you do this experiment with a syringe with a 6 cm diameter?