Why, when acetone is set to evaporate and the temperature is recorded, does the temperature decrease to about 5 deg. C. and then increase again as time goes on? Any help would be awesome!
2007-03-31 18:50:07 · 2 answers · asked by Anonymous in Science & Mathematics ➔ Chemistry
The temperature decreases because evaporation is an endothermic process (energy is required to break intermolecular forces) and so the temperature DOES decrease. This, along with the data from other groups in my class and the teacher saying that it should do that, makes me positive that the data is correct. I just want an explanation as to why.
2007-03-31 19:07:26 · update #1
I never knew the temperature of acetone to decrease on its own without energy being taken away. Acetone is very volatile, but the temperature should remain at room temperature. Now I have to go to the lab and experiment with this.
2007-03-31 18:55:37 · answer #1 · answered by simplynxplicable@verizon.net 3 · 1⤊ 1⤋
In theory the temperature should not change until all of the acetone has evaporated. Perhaps the thermometer was not calibrated correctly. Or maybe the thermometer itself was at a higher temperature than the boiling point of the acetone. The acetone may absorb heat from a thermometer that has a higher temperature than the acetone. When thermal balance is established the temperature may finally equalize and stop falling.
2007-04-01 01:59:26 · answer #2 · answered by physandchemteach 7 · 1⤊ 1⤋