evaporation
2007-06-11 21:41:02 · 4 answers · asked by lazel_25 1 in Science & Mathematics ➔ Engineering
a lack of air pressure.
2007-06-11 21:45:32 · answer #1 · answered by serfdom 2 · 0⤊ 0⤋
Amended:
If the liquid and its vapor - combined is the closed system, then reducing the pressure will lower the boiling point and allow some of the liquid to evaporate from heat removed from the liquid itself. You have not really added thermal heat to the system, you have changed the conditions and the fluid has adjusted itself to a new equilibrium at the new condition.
However, you have expended some work on the system by reducing that pressure. If you restore the pressure the fluid will go back like it was ( providing there was perfect thermal insulation).
Is this what is called an Adiabatic process ? I don't remember; it has been a while.
2007-06-12 11:02:10 · answer #2 · answered by Bomba 7 · 0⤊ 0⤋
You cannot. The latent heat of vapourization has to come from somewhere. If no other source is there, it will be taken from the liquid itself, which will cool.
When this happens the liquid is cooler than the surroundings. Heat now flows from the ambient to the liquid.
This is how desert coolers work. Clothes hung out on a line dry.
2007-06-11 23:23:14 · answer #3 · answered by A.V.R. 7 · 1⤊ 0⤋
put it in a vacuum.
2007-06-11 23:42:21 · answer #4 · answered by Anonymous · 0⤊ 0⤋