Pressure and Temperature / Pressure and number of Particles

Objectives

  • Explain what happens to pressure when the number of particles in a system changes.
  • Explain what happens to pressure when the temperature of a closed system changes.

Teacher notes and overview of daily lessons

Using LabQuest, plastic syringe, and flasks, demonstrate the relationship between 1) pressure and temperature, and 2) pressure and the number of particles present in a closed system.

Students will share prior knowledge, observe demos, and then break into groups to draw particle diagrams and graphs of pressure vs. volume, pressure vs. temperature, and pressure vs. number of particles.

Detailed Daily Plan

Warm-up/Entry Task

What happens to the pressure in a tire when you add air to it? Why do you think that happens?

Materials (for teacher demo)

  1. Pressure and number of particles demo
  2. Plastic syringe
  3. Flask with stopper, Luer-lock, and plastic tube
  4. LabQuest computer interface
  5. Gas pressure sensor
  6. Pressure and temperature demo
  7. Hot plate
  8. Beaker with water
  9. Timer
  10. Flask with stopper, Luer-lock, and plastic tube
  11. LabQuest computer interface
  12. Gas pressure sensor

Have students share out prior knowledge. While teacher is doing demo on document cam or in front of class, another student can be recording data on whiteboard. Other students can be recording data in their journals.

Lab Procedure

  1. Pressure and number of particles demo
  2. Set up flask with stopper and gas pressure sensor as pictured above (without beaker or water or temperature probe). Make sure Luer lock is in the CLOSED position.
  3. Connect gas pressure sensor to LabQuest computer interface and open data collection window. Have students record the pressure reading.
  4. The number of air particles in the flask can be increased by using the syringe to pump air into the flask. Put syringe at a set volume (like 15mL), then screw on to the Luer lock.
  5. While holding the syringe plunger, open the Luer lock. Push the plunger down, hold, and close the Luer lock. Have students record the pressure reading.
  6. Unscrew syringe from Luer lock and re-set the plunger. Repeat C-D until you have enough data points.
  7. Pressure and temperature demo
  8. Set up flask with stopper and gas pressure sensor as pictured above (without stopper). Make sure Luer lock is in CLOSED position.
  9. Connect gas pressure sensor to LabQuest computer interface and open data collection window. Have students record the pressure reading.
  10. Place set-up on hot plate. Have students record pressure readings every minute on their data chart.

Data Table

Data Table – Pressure and number of particles

Number of “puffs” / 0 / 1 / 2 / 3 / 4
Pressure (kPa)

Data Table – Pressure and temperature

Time (minutes) / 0:00 / 1 / 2 / 3 / 4
Pressure (kPa)

Split the class into 3 groups and assign each group a “relationship” to draw (particle diagram) and graph:

  1. Pressure and Volume
  2. Pressure and number of particles
  3. Pressure and Temperature

Share out. Compile information on class poster.

Exit Slip

  1. What’s happening to the air molecules in each flask?
  2. If I measure the pressure, what will I find and why?

Pressure and number of particles

Hypothesis:

If ______

then ______

because ______

______

Data table

Number of “puffs” / 0 / 1 / 2 / 3 / 4
Pressure (kPa)

Pressure and number of particles

Hypothesis:

If ______

then ______

because ______

______

Data table

Number of “puffs” / 0 / 1 / 2 / 3 / 4
Pressure (kPa)

Pressure and temperature

Hypothesis:

If ______

then ______

because ______

______

Data Table

Temperature
(°C) / 30 / 35 / 40 / 45 / 50
Pressure (kPa)

Pressure and temperature

Hypothesis:

If ______

then ______

because ______

______

Data Table

Temperature
(°C) / 30 / 35 / 40 / 45 / 50
Pressure (kPa)