6 The Effect on Temperature of Filling the Cooker-Pails One-Fourth, One-Half, Three-Quarters, and Entirely Full
Materials
Cooker or hay-box pail of eight quarts’ capacity
Pail of two quarts’ capacity
“Space adjuster”
Water
Thermometer
Notebook and pencil
Fill the large cooker-pail one-fourth full of water. Bring it to a boil and put it into the cooker for a definite period of time, not less than one hour. Record the resulting temperature. If desired to make the test more comprehensive, leave the water in the cooker for six, nine, or twelve hours, being careful to allow the cooker to become cold between each test. Perform the same experiment with the same pail one-half full, again when it is three-fourths full, and again when entirely full. Record the results in tabular form and compare them. Repeat these tests with a pail of two quarts’ capacity. What is the influence on temperature of having pails partially, or completely, filled?
The explanation is that evaporation takes place in partially filled pails.