The combined experiments of Robert Boyle and Jacques Charles are important in the study of gas characteristics. The purpose of this experiment is to explore the works of both these scientists to further understand the Gas Laws and their applicability. The Introduction Section includes background information for the experiment and provides guidance on what we want to accomplish from this experiment. The Methods Section lays out the procedure to conduct an experiment with the simulator to explore Gas properties. In the Results Section, we cover important information gathered, including data and actual experiment proceedings. In the Discussion Section, we discuss what actually happened during the procedure and the data collected during the experiment, comparing this to the hypothesis and known information. We will also explore what this data is used for and how it helps calculate information in terms of our goals. The Conclusion Section reviews the gathered information, compares it to the original experiments, addresses the importance of such findings and how it applies to outside works.
Introduction:
In the seventeenth century, scientist Robert Boyle explored the properties of gases. He found, after experiments, that at a constant temperature for a fixed mass, a gases volume and its pressure are inversely proportional. To test Boyle’s Law, the experiment must be set up to change the volume of a gas and determine changes to the gases pressure. Boyle’s law can be expressed as P 1 V 1 = P 2 V 2 = k which can help in determining the pressure of a gas in the event of a volume change and the volume of a gas in the event of a pressure change. The kinetic model is useful in explaining this event. Gas particles will travel in a straight line within a closed system, until they collide with another particle or the container’s walls. As the particles collide with the wall, they exert a force on the container. If the container’s size was to be reduced, the gas particles would be allowed to travel less, causing more frequent collisions against the container walls. This would increase the force that the gas exerts on the container. Therefore, we can say that if at a fixed mass, a volume of gas is decreased, the pressure would increase.
In the late seventeen hundreds, another scientist Jacques Charles studied the effects of temperature on gas under constant pressure. His experiments were helpful in determining the volume of a gas as the temperature changes and vice versa. = is useful in expressing Charles’ law. As pressure remains constant, any change in volume on the gas will cause a change in temperature on that gas and vice versa (Wikipedia, 2011).
During this experiment, fundamental assumptions for ideal gases apply as follows:
The goals of this experiment are:
Methods:
Part I:
Part II:
Part III:
Results:
The pump was pumped two times to introduce Heavy Species gas molecules into the gas chamber. Exhibit A shows the results of the introduction of Heavy Species gas molecules.
As shown above, Heat was stable at 300K, pressure varied from about 1.24 – 1.32 atm. The Heavy Species molecules were at 250.
It is my hypothesis that if the gas molecules are doubled, then temperature will remain constant, but pressure will increase two fold to approximately: 2.5 atm.
The same number was used for the Light Species, which was then sent into the gas chamber. Exhibit B shows the results for this experiment.
As shown above, Temperature decreased approximately 18 K and pressure increased to approximately 2.20 – 2.30 atm. This is relatively close to my hypothesis.
The simulator was reset and staged to test Part II. The Heavy Species molecules were pumped into the gas chamber at 250.
It is my hypothesis that if the volume of the chamber decreases, then temperature will increase and pressure will increase. Exhibit C shows the chamber at its final position.
As shown above, temperature increased to approximately 685 K and pressure increased to approximately 4.65 atm. The effective volume of the chamber was approximately divided in half.
The simulator was reset to stage for Part III. The Heavy Species would remain at 250 with the original volume of the chamber constant.
It is my hypothesis that if the heat were turned on, the temperature in the chamber would increase and the pressure would also increase. Exhibit D shows the results of this experiment on temperature changes.
As shown above, temperature was increased to 617 K and pressure increased to 2.60 atm.
By keeping a parameter constant we can test Charles’ Law and Boyle’s Law. Using the simulator, we apply the same simulator conditions but keep both Temperature (Boyle’s Law) and Pressure (Charles’ Law) constant on two separate experiments.
Discussion :
At the onset of this experiment, we maintained no constant parameters with the exception of molecule. When the amount of molecules was doubled in the gas chamber, with a constant volume, pressure increased. This is due to the increased amount of molecules. As the molecules enter the chamber, they travel less distance before colliding with each other or the chamber walls. This increase in frequency of collisions on the wall increases the force against the chamber walls. With an increase in force on the chamber walls, pressure therefore increased. In the second part we decreased the volume of the chamber, which effectively contributed to less molecule travel and increased collision frequency and thus pressure increased. Because temperature was not maintained constant, we can use the simplified PV=T, where volume decreased, making pressure increase, resulting in the required temperature increase for a balanced equation shift.
To calculate volume, we input numbers to obtain an estimated volume change.
(1.27 Atm/4.65 Atm)(100%/V) = 300 K/685 K
Final volume = 62.4% of original volume.
When testing Boyle’s Law, we maintain temperature constant while decreasing volume. When: P 1 V 1 = P 2 V 2
we can find the exact volume change be inputting the values from the experiment.
Therefore final volume equals 53.7% of original volume.
In testing Charles’ Law, we maintain pressure constant and decrease temperature. When: V1/T1 =V2/T2 we find the change in volume on the simulator by inputting the data values from the experiment.
Therefore final volume equals 34.3% of original volume. It is important to note that no volume field was given in the simulator which means we have to use percentages when estimating value.
Conclusion:
All the experiments conducted were successful in replicating key concepts from Boyle’s and Charles’ historical findings. With respect to assumptions and a constant mass and temperature, a gas change in pressure is inversely proportional to subsequent change in volume. This concept proves invaluable in many fields of science. A real life application of Boyle’s law can be illustrated in the event of scuba diving. When a bubble rises up toward the surface, it increases in size as the pressure of higher waters decreases. Charles’ law has shown that volume of a gas can be determined by changes in temperature. This is increasingly important as gases are often used in a plethora of applications in power generation. For example, increased temperature limits in a high pressure air system are important to understand in a closed system to prevent personnel injury and system damage.
References:
Ideal gas. (2010, December 19). In Wikipedia, The Free Encyclopedia . Retrieved 13:40,
