fractional distillation quick question..??

[samiira]

Are there 2 types of fractional distillation..??
i think There is a simple one and a more complex one.. with the simple one it has that fractionating column and condensor.. but which molecules will come out first..?? is it the one with the lower boiling point ..?? and does this concept also go for the complex fractional distillation with the trays and bubble caps ..??

[Martoman]

Tray bubble cap -> industry distillation. Big fractioning tower

Smaller lab one -> in a flask.

Exact same principle. In the lab small beads do the same thing as the bubble caps and trays. They help purify the thing by continually condensing and vaporisong.

At the top you have the lowest mass. Because it is the lowest temperature at the top. I usually think about it as a *line* on the globe of the world starting in africa going north. As you go higher up you head towards the north pole (cooler) but down the bottom your in the freaking sahara.  8-)

[samiira]

So in both process, the ones with the lower boiling point come out first?

[m@tty]

The species at the top of the flask/tower is not necessarily of the lowest mass (though it may well be). It is the most volatile component.

EDIT:

So in both process, the ones with the lower boiling point come out first?

Yes.

[samiira]

Thanks Heaps..  :-]

[vea]

I thought that in the industry distillation, all species come out at the same time but in different locations?

Sorry for the thread revival but I really need some clarification.

[luken93]

I thought that in the industry distillation, all species come out at the same time but in different locations?

Sorry for the thread revival but I really need some clarification.

Nah, they all start at the bottom in a gaseous state. They then rise into increasingly cooler conditions, and when the boiling point of a compound is reached, it will condense at that level. The rest will continue rising to the very top.

[vea]

Thanks luken, should be all good now.