EXERCISE 8 



WHAT EFFECT IS PRODUCED UPON A VOLUME OF AIR BY A CHANGE 



IN ITS TEMPERATURE? 



Materials. A glass flask or bottle ; a one-holed rubber stopper which fits the flask or bottle ; a 

 glass tube about 18 inches in length ; a drinking glass or other similar vessel. 



Directions. Insert one end of the glass tube through a one-holed rubber stopper, then place the 

 stopper in the neck of the flask or bottle. Hold the apparatus in an inverted position with the free 

 end of the tube in a vessel of water. Warm the flask with the hands. What occurs ? Keep the hands 

 on the flask as long as there is any result. Then remove the hands, but keep the end of the tube 

 under water and allow the flask to cool, noting what happens. 



Explain the results you have seen. What have you learned about the behavior of air when 

 heated ? when cooled ? 



Additional problems. When an automobile tire has been pumped full of air in the early morning and 

 then allowed to stand in the sunlight for some hours, it sometimes bursts. Why ? 



One type of glass fruit jar is sealed by applying the cap to the jar while the jar and contents are hot, 

 the cap not being screwed or clamped to the jar. What holds the cap on the jar ? 



Could the flask and tube of the above exercise be used as a thermometer ? 



