Purifying organic liquids help

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Bertybassett
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Hi, I am slightly confused on the steps and order of purifying an organic liquid. So i've seen a couple of sources say use a separating funnel, but my textbook says that this is done when the product is insoluble in water? if we were purifying say an ester, surely this is soluble in water? so why would we use the separating funnel?

am I correct in thinking that after this, we then add a drying agent, filter to remove the dring agent, then carry out distillation?

Do you always add the drying agent first (then fitler), and then distillation?

i'm basically a little confused on the order and when and why we use the separating funnel?

thanks
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Chinemerem1
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(Original post by Bertybassett)
Hi, I am slightly confused on the steps and order of purifying an organic liquid. So i've seen a couple of sources say use a separating funnel, but my textbook says that this is done when the product is insoluble in water? if we were purifying say an ester, surely this is soluble in water? so why would we use the separating funnel?

am I correct in thinking that after this, we then add a drying agent, filter to remove the dring agent, then carry out distillation?

Do you always add the drying agent first (then fitler), and then distillation?

i'm basically a little confused on the order and when and why we use the separating funnel?

thanks
You distil, then drying agent, then carry out redistillation.

The separating funnel has two layers, aqueous and organic, so I would assume esters are immiscible in water, since esters are organic. When I think back to GCSE I remember one of the properties of perfumes/esters is that they should be insoluble in water they don't wash off easily.
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Bertybassett
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that's not the order others have said though. so are all organic liquids immiscible/insoluble?
(Original post by Chinemerem1)
You distil, then drying agent, then carry out redistillation.

The separating funnel has two layers, aqueous and organic, so I would assume esters are immiscible in water, since esters are organic. When I think back to GCSE I remember one of the properties of perfumes/esters is that they should be insoluble in water they don't wash off easily.
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Claisen
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Long chain esters = not miscible in water therefore we can using liquid-liquid extraction (separating funnel).
Short chain esters = miscible in water therefore we can use distillation.

Dehydrating agent is good for removing water / aqueous acid catalyst. If you are interested in chemistry, you could read up about the Dean-Stark apparatus.
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Chinemerem1
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(Original post by Bertybassett)
that's not the order others have said though. so are all organic liquids immiscible/insoluble?
I was going off my textbook (OCR).
No, polar organic liquid are usually soluble.
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Bertybassett
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#6
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this vid uses a different order https://www.youtube.com/watch?v=8oKC0EYoHbQ
(Original post by Chinemerem1)
I was going off my textbook (OCR).
No, polar organic liquid are usually soluble.
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