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Phase diagram issues

Hiya, so this may end up being a bit of data overload but I'm in the midst of writing a lab report and can't seem to get this phase graph right and I can't seem to find the issue?
Basically these are the recorded experimental results which is just the boiling points and refractive index of the acetone-chloroform mixture and the graph plotted to try and calculate the molar fraction

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This led me to calculate the molar fraction values to be as follows

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But considering that the more vapour there is in the mixture, the less liquid there should be? That's what confused me and the values are pretty similar for both :confused:

I also had to draw the phase diagram for this mixture based off these values, at first I got 2 very similar lines, and only got this after reversing the order of the X_A liquid values which still isn't right.

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I know this is a long shot as it is quite specific, but if anyone has any ideas I'd be super grateful :h:

Reply 1

langlitz

Original post by KaylaB

So why did you reverse one of the final graphs? I'm not 100% sure, but I'd think they should be similar shape but with the vapour line slightly above the liquid phase line

Reply 2

KaylaB

Original post by langlitz

So why did you reverse one of the final graphs? I'm not 100% sure, but I'd think they should be similar shape but with the vapour line slightly above the liquid phase line

As it's supposed to look similar to this, and reversing was the only thing was gave me which remotely resembles that :s-smilie:

Reply 3

langlitz

Original post by KaylaB

As it's supposed to look similar to this, and reversing was the only thing was gave me which remotely resembles that :s-smilie:

Yeah sure, but it doesn't necessarily need to have a high boiling azeotrope like in that diagram

Edit: and I can't really think of a way for justifying reversing the values :tongue:

(edited 7 years ago)

Reply 4

KaylaB

Original post by langlitz

Yeah sure, but it doesn't necessarily need to have a high boiling azeotrope like in that diagram

Edit: and I can't really think of a way for justifying reversing the values :tongue:

Yeah I suppose, and the data could also be to blame, considering it was a collaborative effort. We had 6 pairs of people doing 2 each, so different sets of apparatus and all that. :dontknow: