Phet Simulation Lab and Graphing Exercise: Gas Laws Access phet simulator for gasses by going to: Click on "Laws" Pump "bike" pump twice to put air in container Don't forget the conclusion questions on the last page. Boyle's Law Experiment Change Hold constant to Temperature Do not add or take away any gas Record current pressure below next to 2L volume. Increase the size of the container by dragging out the handle to the left as far as it can go. Record pressure next to 3L volume. Decrease the container size as small as it will go. Record pressure next to 1L volume. Note: The temperature should not have changed each trial. If it did, follow the directions closely and repeat the experiment. Pressure Volume Temperature 1 L 300K 2 L 300K 3 L 300K Sketch a graph of your data below (double click the graph, then click on to draw a solid line through approximate points based on data above) Charles's Law Experiment Reset simulation by click orange circle on the lower right Put two pumps of air in the chamber Change Hold constant to Pressure T Do not add or take away any gas Record current pressure and temperature below next to 2L volume. Increase the size of the container by dragging out the handle to the left as far as it will go. Record pressure and temperature next to 3L volume. Decrease the container size as small as it will go. Record pressure and temperature next to 1L volume. Note: The pressure should not have changed in each trial. If it did, follow the directions closely and repeat this experiment. Pressure Volume Temperature 1 L 2 L 3 L Sketch a graph of your data below (double click the graph, then click on to draw a solid line through approximate points based on data above) Gay-Lussac's Law Experiment Reset simulation by click orange circle on the lower right Put two pumps of air in the chamber Change Hold constant to Volume Do not add or take away any gas Lower the temperature to 100K by clicking the slide at the bottom to cool (approx 100 is ok). You can see where the temperature is in the top right of the container. Record pressure. Increase temperature to 200K. Record pressure below. Increase temperature to 300K. Record pressure below. Increase temperature to 400K. Record pressure below. Note: The volume of the container should not have changed in each trial. If it did, follow the directions closely and repeat this experiment. Pressure Volume Temperature 2 L 100K 2 L 200K 2 L 300K 2 L 400K Sketch a graph of your data below (double click the graph, then click on to draw a solid line through approximate points based on data above) Conclusion/Questions: A positive slope indicates a direct relationship between two variables whereas a negative slope indicates an inverse relationship. Direct relationships can be summarized by saying when one variable increases, the other increases. When one decreases, the other decreases. A negative slope is an inverse relationship so when one variable decreases, the other increases and vice versa. Which law(s)/graph(s) had a positive slope? Which law(s)/graph(s) had a negative slope? Which law(s)/graph(s) showed a direct relationship between the variables? Which law(s)/graph(s) showed an inverse relationship between the variables? Summarize the relationship between pressure and volume for Boyle's Law. When pressure increases, volume ______________. Summarize the relationship between volume and temperature for Charles's Law. When temperature increases, volume _____________. Summarize the relationship between pressure and volume for Gay-Lussac's Law. When temperature increases, pressure ______________. For the variables pressure, volume, temperature, and moles, which variable did not change through all of these experiments and how do you know? For the next two questions, think about pressure. Pressure is defined as force per unit of area and is caused by collisions of gases against the walls of a container. With that in mind, answer the following: Why does pressure increase when the gas particles are moving faster assuming the volume remains constant? Why does pressure decrease when the container size increases assuming temperature remains constant