In Excel complete the following for Boyle’s Law results:
Two Raw Data Graphs
Two Linear Graphs
Boyle’s Law Experiment Results:
Experiment 001
Volume (mL) / Pressure (Torr)4 / 859.5
6 / 426.9
8 / 166.4
10 / -8.4
12 / -127.2
14 / -217.4
16 / -282.9
18 / -334.6
20 / -375.3
Experiment 012:
Volume (mL) / Pressure (Torr)3 / 966.5
5 / 618.7
7 / 310.6
9 / 70.7
11 / -131.5
For Pressure – temperature relationship results complete Excel graphs for the following:
Graph, Data Table and Equation [Temperature, K]
Absolute Zero Graph [Temperature, Celsius]
Gay-Lussac’s Law Experiment Results (Pressure-Temperature Relationship):
Temperature (c) / Pressure (Torr)28.7 / 29.2
87.1 / 161.4
8.2 / -14.8
24.8 / 22.1
Information for Graphs:
- Graph the raw data from each of the two Boyle’s law data sets. When you examine your data table, you will see two columns. One is labeled Volume, mL. This is the actual volume of the confined gas. The second column is labeled Pressure/torr. This is the sensor pressure. To obtain the actual pressure of the gas sample, the barometric pressure (Const1:) must be added to the sensor pressure. The precision of the pressure transducer is 0±750 torr. Use three significant figures on the actual pressure values. Hand draw the best-fit curves.
- Manipulate the data to obtain a straight-line graph for each data set. Display the equation for the line and the R2 value on each graph.
- Graph the raw data from the Gay-Lussac experiment to obtain a straight line. You will have to calculate the temperature in K and the actual pressure by using the barometric pressure as above. Display the equation for the line and the R2 value on each graph. The precision of the thermometers is ±0.0001 °C so adding 273.15 will limit the significant figures of the calculated temperature values.
- To determine absolute zero, reverse the axes and plot temperature (°C )versus Pressure (torr) to obtain a graph where the y-intercept that represents “absolute zero” for the experiment.
Using the information from the Graphs- answer the following:
Boyle’s law
- Compare and contrast the linear graphs obtained from the two data sets. How are they similar? How are they different? Be very specific.
- Examine the raw data. If the volume is doubled from 10.0 mL to 20.0 mL what does a ratio of the data show happens to the pressure? Express your answer mathematically. What did you expect to happen when the volume doubled?
- Examine the raw data. If the volume is halved from 20.0 mL to 10.0 mL, what does a ratio of the data show happens to the pressure? Express your answer mathematically. What did you expect to happen when the volume halved?
- From your answers to questions 2 & 3 and the shape of the raw data plot, do you think the relationship between pressure and volume of a confined gas at constant temperature is direct or inverse? Explain your answer.
- Using the equations for the lines (y=mx+b)from your linear graphs calculate the pressure at a volume of 2.5 mL. Report this as an average value and show all work.
- Using the equations for the lines (y=mx+b)from your linear graphs calculate the pressure at a volume of 50.0 mL. Report this as an average value and show all work.
Gay-Lussac’s Law
- Using the equation for the line (y=mx+b)from your graph calculate the pressure at temperatures of 200K and 400K. Show all work. What does your calculation show happens to the pressure when the temperature is doubled? Express your answer mathematically as a ratio. What did you expect to happen when the temperature doubled?
- Examine the intercept for the equation for the line where you plotted temperature (°C ) versus Pressure (torr). Calculate a percent error for absolute zero. The temperature must be °C for this calculation.
- How could the experimental design be improved to obtain a more accurate value? Be specific.