4E30.20 - Constant Volume Gas Thermometer

See paragraph one in the procedure section.
Code Number:
Demo Title:
Constant Volume Gas Thermometer
Volume vs. Pressuer
Area of Study:
Heat & Fluids
Constant Volume Gas Thermometer

Place the marking tab at the top of the green liquid before heating the bulb.  Heat the bulb with your hands or CAREFULLY with a grill lighter.  Note that the liquid level moves away from the marking tab as the gas expands.  Raise the other movable side of the manometer until the liquid level is once more even with the marking tab.  Your volume is now the same as when you started even though the temperature and pressure are higher.  

Ice can also be used to cool the bulb for a contraction mode of operation.

  • Roger Blickensderfer, "Physics in Chemistry Lab", TPT, Vol. 32, # 1, Jan. 1994, p. 18. 
  • Allan P. Feldman, "A Model of the Savery Steam Engine", TPT, Vol. 19, # 6, Sept., 1981, p. 414.
  • Edward V. Lee, "Determination of Boltzmann's Constant", TPT, Vol. 13, # 5, May 1975, p. 305.
  • Marvin Ohriner, "A Constant Volume Gas Thermometer", TPT, Vol. 9, # 4, April 1971, p. 197.
  • Phillip O. Berge, G. Ulrich Nienhaus, and Jeffrey B. Ziegler, "Constant Volume Gas Thermometer Without Mercury", AJP, Vol. 62, #7, July 1994, p. 666.

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