Separating Mixtures: Does the Order Matter in Physical Methods?

[fatherlewis]

when separating mixtures using only physical methods, does the order in which you separate them mater?

for example, if i had had urea and napthalene in the mixture...both are water soluble...so to take the urea out i first take out the napthalene through sublimitation and then the urea through water solubility filtration (evaporation the water)...so if i hadn't taken the napthalene out first would that affect anything in the grand scheme of things?

 

[Borek]

Naphthalene is not water soluble.

And yes - sometimes selecting correct order allows separation.

 

[GCT]

when separating mixtures using only physical methods, does the order in which you separate them mater?

for example, if i had had urea and napthalene in the mixture...both are water soluble...so to take the urea out i first take out the napthalene through sublimitation and then the urea through water solubility filtration (evaporation the water)...so if i hadn't taken the napthalene out first would that affect anything in the grand scheme of things?

I am not familiar with this method however my impression was that sublimation is relevant to a solid. How do you plan to collect the naphthalene? I am not certain if there are any concerns with boiling an aqueous solution of naphthalene since it has a freezing point of 80 C - 90 C.