I Background Boyle’s Law states that the volume of a fixed mass of gas varies inversely with pressure at a constant temperature. II Purpose The purpose of this experiment was to show that the pressure on the air in the syringe was varied because of Boyle’s law, which states that the volume of a fixed amount of dry gas is inversely proportional to the pressure, while the temperature is held constant. III Procedure The first step was to adjust the head on a syringe so that there was 35-40mL of air trapped in the syringe, and hold the air by capping the syringe with an airtight plastic tip.
Next was to read the volume of air in the syringe to make it as close to tolerance as the accuracy of the syringe will allow. Next was to record that volume as the initial volume for zero weights in your data table. Then was to balance the first weight on the piston. Then by measuring the chemistry books as a constant mass. Then twisted the piston gently overcoming any frictional forces until the piston had come to a rest. Next was to record the volume of gas inside the syringe, and then repeat the procedure until there were an adequate number of books balanced on the piston.
After reaching about four books then was to remove the books and allow the system to return to zero pressure. Next was to repeat each step a second time. It was important to know that to get the volume back to the original reading it might take twisting the piston several times. Last was to repeat the fourth step, giving three separate sets of data for each of the five pressure measurements. IV Conclusion w/ Calculations and Analysis # Books “pressure”| Trial 1 Volume| Trial 2 Volume| Trial 3 Volume| Average Volume| 0| 40| 40| 40| 40|.
1| 29| 39| 31| 33| 2| 24| 26| 24| 24. 6| 3| 19| 19| 20| 19. 3| 4| 16| 15 | 16| 15. 6| 5| 14| 14| 14| 14| Calculated Averages: 40 + 40 + 40 / 3 = 40 29 + 39 + 31/ 3 = 33 24 + 26 + 24 /3 = 24. 6 19 + 19 + 20 /3 = 19. 3 16 + 15 +16 /3 = 15. 6 14+ 14 +14 /3 = 14 This experiment proves Boyle’s Law by showing that when pressure increases volume decreases. The more books placed on top of the syringe minimize the volume of the air inside the syringe.
This is shown very clearly in graph one. Gases are compressible because their molecules are more spread out and when the pressure increases they become more compact and the volume decreases. The kinetic molecular theory states that all molecules are in constant motion, because they are in constant motion it is easier for them to become more compact. By creating an inverse graph of the volumes it is possible to find volumes for pressures that were not physically tested.
This shows the mathematical proportion, which then relates to the formulas that develop (such as V1, P1, and T1), that exist to find the variables that are needed to solve the calculations. Some sources of error during the experiment could be switching off with other groups books so the books that were being used were different every time, although this could only create a very small amount of error in the results. Another source of error could have been human error from misreading the measurement of the volume on the syringe.
One more source of error could have been starting the syringe trapped at 40 mL of air because it could have changed slightly from one trail to another. Since it is physically hard to balance five books on top of a syringe without breaking the syringe it proves to limit the amount of data that should be gathered to make a full analysis. When repeating this experiment to eliminate error I would use five of the same chemistry books, have two people holding the tube at all times, and have one designated measurement reader.