Acetone, CH_3COCH_3, is a laboratory solvent that is also commonly used as a nai
ID: 536280 • Letter: A
Question
Acetone, CH_3COCH_3, is a laboratory solvent that is also commonly used as a nail polish remover. a. Describe the submicroscopic events taking place at the surface of liquid acetone when it evaporates. b. Do all of the acetone molecules moving away from the surface of the liquid escape? If not, why not? What three criteria must be met for a molecule to escape from the surface of the liquid and move into the gas phase? c. If you spill some nail polish remover on your hand, the spot will soon feel cold. Why? d. If you spill some acetone on a lab bench, it evaporates much faster than the same amount of acetone in a test tube. Why? e. If you spill acetone on a hot in the laboratory, it evaporates much more quickly than the same amount of acetone spilled on the cooler lab bench. Why?Explanation / Answer
Describe the submicroscopic events taking place at the surface of liquid acetone when it evaporates.
Ans:Molecules of acetone evaporate, forming a vapor. Condensation of some of the acetone molecules takes place upon losing kinetic energy.
Do all of the acetone molecules moving away from the surface of the liquid escape? If not, why not? What three criteria must be met for a molecule to escape from the surface of the liquid and move into the gas phase?
Ans:Not all of the acetone molecules moving away form the surface escape because only some of the molecules have sufficient energy to escape the surface and move into gas phase, others will condense back upon collision with other molecules.
If you spill some nail polish remover on your hand, the spot will soon feel cold. Why?
Ans:The evaporation of the solvent used in the nail polish remover causes a decrease in thermal energy- making the surface cooler.
If you spill some acetone on a lab bench, it evaporates much faster than the same amount of acetone in a test tube. Why?
Ans:The nail polish remover that is spilled on the bench has a far larger surface area, which leads to an increased rate of evaporation.
If you spill acetone on a hot plate in the laboratory, it evaporates much more quickly than the same amount of acetone spilled on the cooler lab bench. Why?
Ans: Increased temperatures speed of the rate of evaporation.