Marcel slowly heated cold water until
it boiled, and he checked the temperature every minute. He recorded his results
in the data table below.
Use the information provided above to
answer the questions below.
22. Marcel repeated the experiment using a sealed lid on the
container while heating the water at the same rate as before. As a result of
the added pressure, he should expect the temperature by the experiment to be:
a) Higher than 100*C.
b) Lower than 100*C.
c) Still at 100*C.
d) There is no way to predict what it should be in this case.
The best answer is a.
This occurs because higher pressure increases
the boiling temperature, while decreasing the pressure lowers the boiling temperature
(Think of cooking a hot dog in boiling water on a fire on a high mountain. Objects
take longer to cook in boiling water where the air pressure is lower (in the
mountains) because they don't get as hot.)
--------------- ---------------
Slichter