getting from C6H12O6(aq) to C6H12O6(l) (1 Viewer)

kooltrainer

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In a multiple choice test i had recently, it asked for the process to get from ethanol (aq) to ethanol (l) where ethanol (aq) was from the fermentation process.

it was a choice between distillation and filtration. I know (probably) sum textbooks say distillation but this process would only give approximately 96% ethanol.research was done saying that a recent discovery made it possible to use filtration using zeolites instead of the distillation process. the zeolites would selectively attract the polar sections of the ethanol so that pure ethanol passes out, leaving water molecule behind.

Most people would've wrote distillation like the textbook and the teachers would assume its distillation . but filtration also works u see..
any comments? am i correct? should i get a mark? am i wrong? correction?
 
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dan.121212

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uh C6H1206 is glucose, i think ya mean C25H5OH(aq) ----> C2H5OH(l)
 

jcurry

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if your teaching marks you down for it, just show them the research that shows that filtration can be used cause as you said most people probably only know about distillation
i would of just answered distillation as that is the safe answer
 

kooltrainer

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dan.121212 said:
uh C6H1206 is glucose, i think ya mean C25H5OH(aq) ----> C2H5OH(l)
o ya.. C25H5OH(aq) ----> C2H5OH(l) not glucose.. hehe
and it was my tutor who said that zeolite could be used instead of the distillation process.. but couldnt find specific info abt it on net..
 
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xiao1985

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Nice discovery. Despite the fact that I usually encourage ppl to find out more about recent scientific discoveries, writing it in the HSC risks the marker NOT knowing the most advance scientific discovery, and getting penalised.
 

namburger

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Jackiee, the question was in a flow chart format
If you noticed in certain parts of the flowchart, that after filtration, the flow chart split into filtrate and solid residue . In that question, there was only one box after the unknown. It would be logical to pick distillation.
If this weren't multiple choice, than it could be easier to argue for your mark by just showing your extended research.
Other than that, relax, just 1 mark.
 

kooltrainer

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lol..
not fair man.. teachers cant be bothered updating with contemporary chemistry ..
filtration from ethanol(aq) to ethanol(l) still works.. so theres 2 answers to that multiple choice.. o_O.. everyone who picked that answer shuld get a mark..
 

undalay

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1 MARK? 1 MARK? 1M ARK?

Q1. OH i got it wrong dw just 1 mark.
Q2. homg i got it wrong dw just 1 mark.
Q3. WTF ? dw just 1 mark.
....
end of test.

DW i just lost 1 markers.

get resultback 0%.

1 mark is alottt ):

but since its an internal test, i'm sure you can argue for the mark.

You'll need to do two things.

1. Show why distillation cannot be an answer
2. Show why filtration can be.

Doing 2 is not enough, as multiple choice is the best answer.
 

kooltrainer

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jcurry said:
http://www.domainb.com/companies/companies_p/praj/20041030_produced.html

talks briefly about using a zeolite in order to seperate a large alcohol molecule and water through filtration
how did u find that.. i couldnt find it my self.. thx a lot.. i could show that to teachers.. but that article didnt specifically say filtration even though it uses a process similar to filtration.. could we still say its filtration?
 
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kooltrainer

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lol and undalay.. since filtration is more up-to-date.. filtration would be the best answer =P .. haha.. they shuld let that questiong go and give 2 answers for it..
instead of me showing that distillation cant be an answer and filtration can be.. they should show me why distillation can be and why filtration cant be.. haha jkjk
 

namburger

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undalay said:
1 MARK? 1 MARK? 1M ARK?

Q1. OH i got it wrong dw just 1 mark.
Q2. homg i got it wrong dw just 1 mark.
Q3. WTF ? dw just 1 mark.
....
end of test.

DW i just lost 1 markers.

get resultback 0%.

1 mark is alottt ):

but since its an internal test, i'm sure you can argue for the mark.

You'll need to do two things.

1. Show why distillation cannot be an answer
2. Show why filtration can be.

Doing 2 is not enough, as multiple choice is the best answer.
Haha ok, 1 mark is a lot. i rage about 1 markers like in our physics zz. but i get over em =]
 

brenton1987

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Aqueous ethanol taken straight out of a fermentation vessel is upwards of 20% ethanol at most. No one would ever run that through a bed of zeolites because it would take months to get it to 100%.
The ethanol would be distilled to 96% before being filtered to break the azeotrope.

I think youre going to have a hard time trying to talk your way into a mark.
 

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