Shawna Hendricks
CHM 144 C
Robert Baum
Colleen Heffner and Andrew Flannery
Abstract:
The hypothesis of whether or not the relationships between the properties of gases will all be direct is experimented. This was done by experimenting three variables of properties of gases such as temperature, pressure, and volume. Temperature and pressure were tested together while volume was kept constant, then the relationship between volume and pressure was tested while keeping temperature constant, and finally the relationship between volume and temperature was tested while keeping pressure constant. All of these experiments were graphed and calculated to prove that the hypothesis was correct. After reviewing the graphs and evidence done in the experiment, it was concluded that the relationships were all direct with one another.
Introduction:
Exploring the properties of gases was the final experiment that was done in lab. Chemical behavior of gases depends on their composition, all gasses have remarkably similar physical properties. Gases can be described physically in four variables: pressure(p), volume(v), temperature(t), and amount (number of moles, n).These gas laws are combined to form an ideal gas law: PV=nRT. R is a proportionality constant known as the gas constant and can be obtained by measuring the volume, temperature, and pressure of a given amount of gas and substituting the values. For an ideal gas those variables can be found by measuring the other one. The ideal gas law quantitively describes the physical state of an ideal gas, even though no such ideal gas actually exists. For the hypothesis, it was calculated that if the pressure goes up the volume will go us as well. This was conducted by the fact that in the equation both P and V next to each other, if one has a big number it will increase the other. It was also calculated in the same way for the relationship between volume and temperature because to find volume one must use temperature. So therefore if temperature is a large number then volume must also be a large number. Finally the relationship between pressure and temperature was calculated that they will both rise together. This was conducted using the same equation as above. After writing these hypothesis and realizing what was written, it really did not make much sense that each one would raise the other. One should really use simple math and keep in mind that certain things are kept constant and not everything would have a direct relationship. That's why the purpose of this experiment is to determine the relationships between two of the four variables in the ideal gas law, while the other two are held constant. In all experiments, n will be held constant because in all experiments will be conducted on an enclosed sample of air. The relationships between the other three variables (P,V,T) will be conducted by holding one of them constant in each of the three experiments and observing the relationship between the other two. Each of the relationships will be tested separately in their own experiment. To test the relationship between pressure and volume at constant temperature, Boyle's law will be used. Using Gay-Lussac's Law the relationship between pressure and temperature will be tested where volume will be kept constant. Finally where pressure was kept constant was the relationship between volume and temperature that will be tested by Charles' Law.
Methods:
Relationship between Pressure and Volume at Constant Temperature This is to study the relationship between the volume of an enclosed gas sample in a 60 mL syringe and the pressure exerts at a constant (room) temperature. Using the plunger to position the pistol of a syringe so that there is a measured volume of air trapped in the barrel of the syringe; adjust the volume to 55 mL. We used the handle to adjust the clamp until its foot was just