Gas Investigation

Name: _________________________________________________________ Date: ________________________ Period: _________ Investigating relationships between P, V & T Something that makes you go “Hmmmmm?” 1. A small helium tank measures about two feet tall. Yet it can fill over 50 balloons! How can such a small tank contain enough helium to fill so many balloons? 2. You decide to go camping one weekend in the summer. When you arrive to your campground, you fill up your air mattress and then go fishing. When you return much later in the evening and discover that your air mattress has deflated some even though it is brand new and has no holes in it. Why did this happen? Set-Up ● Go to the website www.explorelearning.com. At the top right, click “Enroll in a class here.” Enter the following class code: _________________________ and click continue . Make sure the class is your class period and click Register Now. Type in a username as was instructed prior to going to the computers. Click “Launch Gizmo” under the Boyle’s Law and Charles’ Law! The Gizmo shows a container of gas; the little purple spheres represent molecules. Activity A: Boyle’s Law Get the Gizmo ready: ● On the BOYLE’S LAW tab, set the temperature to 300 K and press OK. Question: How does pressure affect the volume of a gas? 1. Form a hypothesis: In this experiment, you will pile weights on the lid of the container of gas. What do you think will happen as more weight is added to the lid? Use a complete sentence in an “If….then…” format and think about everything this might affect! 2. Notice: Look at the DESCRIPTION pane. What is the mass of the lid? _________________ How much pressure does the lid exert on the gas? ________________________________ (NOTE: This model does not include atmospheric pressure, which is 101,325 N/m2.) 3. 4. Collect data: Using the Select mass slider to place weights on the lid, record the pressure and volume of the gas for each of the following settings. Added mass on the lid Total mass (lid + added mass) 0 kg 10 kg 10 kg 20 kg 20 kg 30 kg 30 kg 40 kg Pressure* Volume Analyze: a. As the pressure increases, what happens to the volume of the gas? _____________________________________________ b. Is this an indirect or direct relationship? (FYI: This relationship is called Boyle’s Law) ________________________________ c. Why do you see this relationship between pressure and volume? Use complete sentences describing all changes that occur. The words volume and pressure should not be in your answer, but rather describing what is actually happening to the molecules will help you form the basis of your explanation. 5. Calculate: Compare the pressure and volume values in your data table. a. How did doubling the pressure change the gas volume? Show your work. b. How did tripling the pressure change the gas volume? Show your work. c. How did quadrupling the pressure change the gas volume? Show your work. 6. Predict: If the added mass on the lid was 50 kg, a total mass of 60 kg would exert pressure on the gas inside the container. What would be the volume of the gas? Show your work. 7. Test: Test your prediction using the Gizmo. What is the volume of the gas? __________________ Was your prediction correct? If not, where did you go wrong? 8. Create a graph: Select the GRAPH tab. Set the mass slider to 0 kg, and click Record to plot a point on the graph. Plot a point for each possible mass to create a graph showing the relationship between pressure and volume. Sketch this graph below with appropriate labels, axis, title, and scale! a. 9. How does the shape of the graph illustrate Boyle’s Law? Apply: Think about that small helium tank that can fill 50 balloons from the beginning. What must be true about the helium in the tank compared to the helium in the balloons? Explain using what you learned in this part of the investigation. Activity B: Charles’ Law Get the Gizmo ready: ● Select the CHARLES’ LAW tab. Set the Mass to 0 kg and click OK. Question: How does temperature affect the volume of a gas? 1. Form hypothesis: How will the volume of a gas change as the temperature rises and falls? Use a complete sentence in an “If….then…” format and think about everything this might affect! 2. Collect data: Record the pressure and volume of the gas at each of the given temperatures. Temperature Pressure* Volume 100 K 200 K 300 K 400 K 500 K 3. Analyze: a. As the temperature increases, what happens to the volume of the gas? __________________________________________ b. Is this an indirect or direct relationship? (FYI: This relationship is called Charle’s Law) ________________________________ c. Why do you see this relationship between volume and temperature? Use complete sentences describing all changes that occur. The words volume and temperature should not be in your answer, but rather describing what is actually happening to the molecules will help you form the basis of your explanation. 4. Think about it: Why do you think the pressure was the same in each test? 5. Calculate: Compare the temperature and volume values in your data table. a. How did doubling the temperature affect the gas volume? Show your work. b. How did tripling the temperature affect the gas volume? Show your work. c. How did quadrupling the temperature affect the gas volume? Show your work. 6. Predict: Suppose the temperature was 50 K. What would be the volume of the gas? Show your work. 7. Test: Test your prediction using the Gizmo. What is the volume of the gas? _____________ Was your prediction correct? If not, where did you go wrong? 8. Create a graph: Select the GRAPH tab. Set the temperature slider to 50 K, and click Record to plot a point on the graph. Plot a point every 50 degrees to create a graph showing the relationship between temperature and volume. Sketch this graph below with appropriate labels, axis, title, and scale! a. 9. How does this graph illustrate Charles’ law? Apply: Explain why your air mattress deflated from when you blew it up during the day to when you came back at night based on what you learned in this part of the simulation. Conclusion/Analysis: Answer the assessment questions underneath the simulation. If you are completing this at home, you will need to make your own login information separate from the one you used in class!!!! Choose your first initial and last name as your username. For example: my login for this would be ejohnson.