PROCEDURE
28
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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