GAS LAWS SMORGASBORD LAB

PRELAB: Draw the 4 PVTn relationship graphs.

GOAL: to explain observed phenomena using what you know about the gas laws and kinetic

molecular theory (particle motion).

General Procedures:

  1. List each station in your lab notebook with its number and title.
  2. Answer all questions in your lab notebook.
  3. Wear safety goggles for all stations in this lab.
  4. Leave each station clean and neat!!! I am not your mother.

Station 1: Cartesian Diver

  1. The diver is the small tube half-filled with water inside the 2L bottle. Note the position of the diver inside the bottle as the bottle sits on the lab table.
  2. Squeeze the bottle firmly. What happens to the diver? What are you doing to the gases in the bottle AND the diver when you squeeze?
  3. Now, unsqueeze the bottle. What happens to the diver? What are happening to the gases in the bottle AND the diver?
  4. Squeeze the bottle again and watch the gas in the diver carefully. What happens?
  5. Draw a 5-cell cartoon to record what you observed. Show particles in your cartoon to explain what you observed. Consider PVTn relationships.
  6. What do you think makes the diver behave in this way? Which of the PVTn gas relationships is in action? Explain why.

Station 2: Can Crusher

  1. Put about 10 mL water in the pop can. Heat the can on the hot plate until you can see steam leaving the can (when the water is boiling).
  2. Use the tongs to grab the can near the top and to quickly place the can (opening down) in the ice water bath.
  3. Describe what happened. Lift the can up out of the water bath and describe what you see.
  4. Draw a 5-cell cartoon to record what you observed.Show particles in your cartoon to explain what you observed. Consider PVTn relationships.
  5. Explain what is happening at the particle level at each stage of the process.What PVTn relationships are in action? Explain why.
  6. Would the same thing have happened if you put the can in the ice water bath with the opening up? Why or why not?

Station 3: Balloon Magic

  1. Put about 10mL water in the 250 mL flask.
  2. Heat the flask system on the hotplate until the water is boiling.
  3. Record your observations.
  4. Carefully place the balloon on the top of the flask and observe what happens.
  5. Use the tongs to move the flask to the ice water bath. Record your observations of what happens.
  6. Draw a 5-cell cartoon to record what you observed. Show particles in your cartoon to explain what you observed. Consider PVTn relationships.
  7. Explain what happens to the balloon on the hotplate. What PVTn relationship is in action? Explain why.
  8. Explain what happens to the balloon in the ice water bath. What is happening at the particle level?

Station 4: Happy Birthday

  1. Put a small glob of clay in the center of the shallow dish to hold a birthday candle upright.
  2. Add 1 – 2 centimeters of water to the dish. Add one or two drops of food coloring to make the water more visible. Light the birthday candle.
  3. Place the Erlenmeyer flask mouth down over the candle. Stand it up right in the dish over the candle. Refer to the diagram at right.
  4. Record your observations.
  5. What did you see around the mouth of the flask when you first put it into the water. Explain what is happening.
  6. What effect did the water have on the gas inside the flask? How do you know?
  7. The candle is replacing O2 in the flask with CO2. Explain why water rose into the flask.
  8. Draw a 5-cell cartoon to record what you observed. Show particles in your cartoon to explain what you observed. Consider PVTn relationships.
  9. What PVTn relationships are in action here? Explain why.