CHM 101/102 Laboratory Manual Gas Laws General Chemistry 101/102 Laboratory Manual University of North Carolina at Wilmington

CHM 101/102 Laboratory Manual Gas Laws Purpose Purpose  To study the relationships that exist among the properties of temperature, pressure, and volume for gases.  To learn methods for measuring the temperature, pressure, and volume of gases. Safety Considerations Safety Considerations  There are no special safety considerations associated with this activity.  There are no chemical wastes generated by this activity.

CHM 101/102 Laboratory Manual Gas Laws Part 1: Boyle’s Law Part 1: Boyle’s Law  Open the Applications folder on your computer and double click on the “Microlab” Prompt as shown in the photo.

CHM 101/102 Laboratory Manual Gas Laws Part 1: Boyle’s Law Part 1: Boyle’s Law  Click on the “Gas Laws” prompt and then double click on the “Boyles Law” program to open up the file for the first part of the experiment.

CHM 101/102 Laboratory Manual Gas Laws Procedure: Part 1: Boyle’s Law Procedure: Part 1: Boyle’s Law  Obtain the plastic tubing and two syringes located in the ziplock bag labeled “Gas Laws Experiment”, located in the plastic container for Microlab Equipment.  Disconnect the plastic tubing from the syringe. Connect the fitting of the tubing to the port labeled “Pressure” on the back of the Microlab kit as shown in the picture to the right.

CHM 101/102 Laboratory Manual Gas Laws Procedure: Part 1: Boyle’s Law Procedure: Part 1: Boyle’s Law  Obtain a syringe with a plunger and open the plunger up to the 10 mL mark.  Now, re-connect the other end of the plastic tubing to the top of the syringe.

CHM 101/102 Laboratory Manual Gas Laws  Begin data collection by clicking the “Start” prompt.  While holding the plunger of the syringe steady at 10 mL, type in the value “10” in the keyboard input box.  Click on “Enter and Continue” for the volume and pressure data to be collected.

CHM 101/102 Laboratory Manual Gas Laws  Move the plunger to the 9 mL mark and type in this value in the input box, then press “Enter and Continue”.  Set the plunger to subsequent volume settings (ex. 8, 7, 6, 5 and then up to 6, 7, 8, 9, 10, 11, 12 and 13 mL).  Press “Enter and Continue” while holding the plunger at each volume setting.

CHM 101/102 Laboratory Manual Gas Laws  After you have completed your measurements, press the “Stop” prompt.  Volume and pressure data will be available in the table below the graph, as in the photo shown.

CHM 101/102 Laboratory Manual Gas Laws  Your graph will look similar to the one on the photo, where the red line indicates pressure on the y-axis (in units of torr) versus volume on the x-axis (in mL).  (Ignore the blue line.)

CHM 101/102 Laboratory Manual Gas Laws  Before beginning Part 2 of the experiment you will be asked if you would like to save the data from Part 1. Always click “NO”. Procedure: Part 2: Pressure vs Temperature Procedure: Part 2: Pressure vs Temperature

CHM 101/102 Laboratory Manual Gas Laws  To begin the second experiment open the Applications and Microlab folders.  Click on “Gas Laws” and then double click on the experiment labeled “Pressure vs. Temperature Relationship-CHM 102”. Part 2: Pressure versus Temperature

CHM 101/102 Laboratory Manual Gas Laws  Connect the temperature sensor to the temperature port A in front of the Microlab Kit.  Remove the syringe with the plunger and attach the syringe containing the black stopper to the plastic tubing.  Remove the rubber stopper from the syringe and then push it back in making sure it fits tightly.  Use a rubber band to attach the temperature sensor to the syringe as shown in the photo.

CHM 101/102 Laboratory Manual Gas Laws Procedure: Part 2 Procedure: Part 2  Place the syringe in each water bath, starting with ice water, for two minutes.  Record both the temperature and pressure readings observed for each water bath. ice water room temp hot water

CHM 101/102 Laboratory Manual Gas Laws Procedure: Part 2 Procedure: Part 2  Click “Continue” when the syringe and temperature probe are immersed in the water bath.

CHM 101/102 Laboratory Manual Gas Laws Procedure: Part 2 Procedure: Part 2  Pressure and temperature values will be collected for each water bath.  You may wish to collect data for combinations of water bath temperatures by adding some ice to the tap water, or to the hot water. This will give you more than just 3 data points for your experiment.

CHM 101/102 Laboratory Manual Gas Laws Procedure: Part 2 Procedure: Part 2  When you have finished data collection click the “Stop” prompt.  A graph of pressure on the y- axis (in torr) versus temperature on the x-axis (in Celsius) will be drawn for you, similar to the one in the photo.