Boyles and Gay-Lussacs Law Gas Methods - Research Paper Example

Experiment on Gas Laws – Boyles and Gay-Lussac’s Law By Course: FY014 Tutor: University: Department: Date of Experiment: Date Due Abstract Gas laws can be studied by performing different experiments in a laboratory. This paper is a report on an experiment that had an objective of examining analytically and graphically Boyles and Gay-Lussac’s gas law. Two experiments were done using various apparatus. In the first instance, a valve set at atmospheric pressure was employed in experimenting Boyle’s law. Various recordings were made following the experiment. This experiment confirmed that at a constant temperature and fixed mass of a gas,. Later on, a sealed cylindrical tube that allowed adjustment of temperature was set up to learn about Gay-Lussac’s Law. Readings of temperature, and pressure was recorded at an interval of 10 seconds. After plotting a graph of Pressure against temperature, it became clear that absolute temperature was. Introduction This report covers an experiment that was done on gas laws comprising of Boyle’s and Gay-Lussac’s Law. The experiment aimed at studying both Boyles and Gay-Lussac’s law. The first part of the experiment sort to explore Boyle’s law using a valve set at atmospheric pressure. Various pressures and volumes were observed and counter checked if they were responding to Boyle’s law. The results of the experiment were plotted graphically to confirm validity of Boyle’s law. To study Gay-Lussac’s Law, a sealed cylindrical tube that allowed adjustment of temperature was deployed. Pressure was measured using water Manometer. After turning on source of heat, temperature, and pressure was recorded every 10 seconds. The results were plotted on a graph of temperature v pressures, which affirmed direct proportionality of temperature, and pressure at a constant volume. Theory Boyle’s Law was developed by Robert Boyle in 1661. According to this law, pressure and volume of a specific quantity of air have a relationship if temperature was kept constant. The researcher found out that volume V1 of air exerted pressure P1. On changing the volume of air, Boyle noted that pressure also changed. However, pressure returned to its original point P1 when volume was adjusted back to V1. This observation was made when temperature was kept constant. Boyle graphically demonstrated the relationship between P and V as shown in Figure 1 below. Figure 1:  The graph above shows that pressure and volume had a connection, which was not linear. This implies that for a specific V, it is possible to determine P in a unique way. When Boyle plotted P against 1/V, the result was a straight line as shown in figure 2. This culminated to a conclusion that pressure and volume of fixed quantity of air at a constant temperature were related in the following manner:  (Lionel, 2001) Figure 2:  Following the discoveries above, Boyle deduced that at a constant temperature and fixed mass of a gas,  The second gas law, Charles’ Law, was discovered by Jacques Charles. This law establishes the nature of change in volume of a gas at a constant pressure. The researcher discovered that at a constant mass and pressure of a gas, volume varied linearly with temperature. In a nutshell, keeping mass and pressure constant while increasing temperature of certain quantity of gas would led to an increase in volume of the gas. Charles came up with the following mathematical relationship:  . The simplified form of Charles’ law with T in Kelvin is:  Joseph Louis Gay-Lussac developed the third law called Gay-Lussac Law, which states that Kelvin temperature and pressure are directly proportional. This means that heating up gas makes the gas to move faster consequently building pressure. The relationship between temperature and pressure at a constant volume and in Kelvin Temperature is given by the equation:  It is apparent that pressure, volume, and temperature have a relationship, given fixed amount of gas. This relationship is established in ideal gas law given by: . At a fixed n, the following equation is generated:. Method In the first part of the experiment, a cylindrical tube that allowed adjustment of volume was set up. First, valve was released to enable adjustment of pressure to atmospheric, which was zero on the gauge. While keeping the valve open, connecting rod was pulled to a volume of 50ml. The next step was to close the release valve and proceed to pull the connecting rod out to 100ml mark. At this point, meter reading was obtained and recorded. It was essential to execute the exercise fast to avoid inaccurate results brought about by leakage. On different calibration marks of 150ml, 200ml, and 250ml, corresponding pressures and temperatures were recorded. The entire procedure was repeated five times and average pressure for each volume calculated. By using the values of BAR, pressure in Pascal and in pounds per square inch was calculated. The second of the experiment used a sealed cylindrical tube, which facilitated heating of gas to adjust the temperature. To set the pressure to atmospheric pressure, silicon tube was disconnected. It was then reconnected to mark the start of the experiment. Water Manometer was necessary to measure pressure. Each millimetre difference in level of water represented  At this point, temperature, and pressure reading was obtained and recorded. Source of heat was then turned on and the readings of both temperature and pressure were obtained at an interval of 10 seconds. A graph of temperature v pressure was plotted and examined if it agreed with constant volume law. Results and Discussions The results were tabulated as follows: Part 1 1st 2nd 3rd 4th 5th v p (in Bar) p (in Bar) p (in Bar) p (in Bar) p (in Bar) Total Average p (in kPa) p (in PSI) 100 0.8 0.7 0.7 0.8 0.75 3.75 0.75 75.975 10.875 150 0.6 0.6 0.65 0.66 0.6 3.11 0.622 63.0086 9.019 200 0.4 0.45 0.45 0.4 0.4 2.1 0.42 42.546 6.09 250 0.3 0.3 0.35 0.3 0.3 1.55 0.31 31.403 4.495 The table shows volume and corresponding pressure in BAR. The experiment was repeated five times and average obtained. Pressure in BAR were later converted to kPa and PSI using the equation:  A graph of pressure Vs volume is plotted below. The graph of P vs V shows that the relationship between pressure and volume was not linear. However, on plotting pressure against 1/volume, the graph looked as shown below. v 1/v p (in kPa) 100 0.01 1.013 150 0.006667 0.675333 200 0.005 0.5065 250 0.004 0.4052 The graph shows that p and v are linear in nature. It is clear from the trend line that. This is compared with Boyle’s law, which states that. The value of this constant is 101.3 as shown by the trend line. In a nutshell,. In this case,  The output from the second experiment was in the table below. Part II Temperature Pressure 24 52.3 24 53 24 53.5 24 54 26 54.8 26 55.5 27 56 28 57 29 57.7 29 58.5 30 60 31 63 32 64.5 35 65 37 65.7 37 66.1 37 67 Using the data, a graph of pressure against temperature is plotted as shown below. Equation of the trend line is. X intercept is supposed to show absolute temperature, i.e. temperature when pressure is zero. This is calculated from trend line by equating y to zero:   Absolute temperature is  Conclusion Gas laws were investigated by conducting two experiments. In the first part, the results and subsequent analysis confirms that at a constant temperature and fixed mass of a gas, volume and pressure were related in the form of: . The second part of the experiment shows that on extrapolating the graph of pressure vs temperature, x intercept was. This x intercept is the absolute temperature, i.e. temperature when pressure is zero. Reference list Lionel, R 2001, Principles of Physical Chemistry, Prentice-Hall, New Jersey. Read More