Evan Murphy- N5 Physics Assignment Boyle’s Law AimTo investigate if the pressure of a gas which has a constantmass varies when the volume is changed.
Underlying PhysicsThe particles in different gases have a lot of free space tomove around in which means they tend to collide with each other and bounce offof the container walls. Collisions are likely to occur more often when thevolume is decreased. The particles will have more energy if the temperature isincreased which means that there will be more collisions per second which willmean that particles will collide with a much larger force. Pressure is theforce per the unit of area and can be determined by the equation: P= Pressure in (Pa) F= Force in (N) A= Area in (m2 )The Kelvin scale can change 0 Celsius into -273o K. Toconvert Celsius to Kelvin you simply just do the calculation of (degrees Celsius)– 273, this will give you your answer in Kelvin.
This lets us know the volume ofa selected gas as you can work backwards for example if you know the gas is 243oK you will know the temperature is 30o C. MethodThe air was trapped in a cylindrical container with oil. Thecontainer was connected to a pressure gauge and a pump. The pressure gauge wasthere to measure the pressure and the pump decreased the amount of air whichwas in the cylindrical container.The following values are the results of the experimentpressure against 1/Volume: Air Volume (cm3) 1/Volume(cm-3 ) Pressure 1 (kPa) Pressure2(kPa) Pressure3 (kPa) Average Pressure(kPa) 10 0.1 256 253 259 256 15 0.07 180 180 180 180 20 0.05 148 130 130 136 25 0.
04 109 100 90 100 30 0.03 100 83 77 80 With the results above we plotted a graph with a line of bestfit.AnalysisThe second source I have compares with my own graph as theyare both a straight line which goes through the origin. This shows that ifvolume increases, pressure decreases. Seenext page for second source.
ConclusionThe aim of the experiment I did was to investigate if thepressure of a gas which has a constant mass varies when the volume is changed.The experiment results show that there is definitely some relationship betweenthe change in pressure and volume. EvaluationTo make my experiment more accurate I did the experimentthree times and with these results I calculated the average. Having three setsof results meant that there was more of a chance for an accurate experiment dueto having more values to work with.