A volatile liquid (one that easily evaporates) is put into a jar and the jar is then sealed. Does the mass of the sealed jar and its contents change upon the vaporization of the liquid?

Video transcript

Hello everyone. Today, we have the following problem if Acetone evolves a liquid is placed into a bottle and the bottle is sealed with the total mass of the sealed bottle and its contents change when the liquid vaporizes. So if we were to draw a schematic diagram where we have our container and the bottle is sealed, we would have our liquid particles as follows. And now when this liquid undergoes vaporization will draw a separate line here, it transitions from its liquid phase to its gaseous phase. And the molecules that are near the surface of the liquid will gain enough energy to break away from the cohesive forces of the liquid and escape into the surrounding as vapors. So this these are our liquid molecules and then the molecules that are able to overcome the energy of the liquid cohesive forces can escape as vapors. Now recall that the law of a conservation of mass simply states that the total number or the total mass, excuse me, of the starting material equals the total mass of the end product. So once again, the law of conservation of mass states that the total mass of the starting material must equal the total mass of the end product. And because this system here is closed, we'll actually just make sure that we can illustrate that it is closed and sealed off. This is a closed system. And this means that the Aceto molecules will remain within the system and they therefore, they do not escape into the surroundings. And so, while some of the molecules might change into vapors, the total mass of the sealed bottle and its contents remain constant. So we can conclude that the total mass of the sealed bottle and it's constant content remain constant. And with that, we have solved the problem overall, I hope this helped. And until next time.