PROCEDURE
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SCIENCE PROJECT
ABSOLUTE ZERO
How can the value of absolute zero be determined ?
DEFINITION : Absolute zero is the lowest possible temperature . It is the point at which the atoms of a substance transmit no thermal energy - they are completely at rest . It is zero degrees on the Kelvin scale , which translates to -273.15 degrees Celsius or -459.67 degrees Fahrenheit .
PROCEDURE
1 . Make an ice bath by filling the bucket with ice and adding cool water . The bucket should be 3 / 4 full .
2 . Using the big spoon , stir the ice bath occasionally .
3 . Put the one hole stopper into the dry 125 mL flask .
4 . Set up a hot water bath . The 500 mL beaker should be on the hot plate .
5 . Clamp the 125 mL flask upright so that most of flask is submerged in the hot water bath . ( See diagram 1 )
6 . Boil the water with the empty flask inside it for five minutes . You are doing this so that the gas inside the flask reaches the same temperature as that of the boiling water .
7 . Record the temperature of the boiling water ( which should be the same as that of the gas inside the flask ). Try to get a measurement to 0.1 degrees C . The more precise your measurements are , the more precise your determination of absolute zero will be .
8 . While the beaker is still in the hot water bath , carefully place the short glass rod into the hole in the flask ’ s stopper .
9 . Using the tongs , remove the flask from the hot bath .
10 . Invert the Erlenmeyer flask and place into the ice bath . ( See diagram 2 )
11 . Making sure the flask is underwater , remove the glass rod in the stopper .
12 . Keep the flask submerged in the ice bath for 6-7 minutes , stirring the ice bath occasionally . Water should creep inside the flask . Why ?
13 . Using your fingers , which might get chilly , raise the inverted flask until the water level inside and outside the flask are the same . This is to ensure that the pressure inside the flask is equal to atmospheric pressure . The only variable you want in this experiment is temperature .
14 . Measure the temperature of the water in the ice bath .
15 . 16 . Reinsert the glass rod into the stopper . Take the flask out of the water and set it upright .
16 . Using the graduated cylinder , record the volume of water in the flask as precisely as possible .
17 . Fill the flask to the level where the stopper was .
18 . Using the graduated cylinder , record the total volume of the flask .
19 . Subtract the volume of the water that
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