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So, I'm trying to figure out how to convert ethane to ethanoic acid and the textbook hasn't helped really, anyone know the reagents and conditions?
Much thanks
Original post by Jack_Kavanagh
So, I'm trying to figure out how to convert ethane to ethanoic acid and the textbook hasn't helped really, anyone know the reagents and conditions?
Much thanks


Ethane= Hydrocarbon
Ethanoic acid = Carboxylic acid.

What i'd do is, convert the hydrocarbon into an alochol via 2 nucleophilic subsitutions. You can use NaBr, which would give you bromoethane. You could then add water, and could hydrolyse the bromoethane to get ethanol. This is because of OH ions. Then use potassium dichromate and di h204 and reflux to completely oxidise the ethanol into ethanolic acid. Should work.
Original post by funky2722
Ethane= Hydrocarbon
Ethanoic acid = Carboxylic acid.

What i'd do is, convert the hydrocarbon into an alochol via 2 nucleophilic subsitutions. You can use NaBr, which would give you bromoethane. You could then add water, and could hydrolyse the bromoethane to get ethanol. This is because of OH ions. Then use potassium dichromate and di h204 and reflux to completely oxidise the ethanol into ethanolic acid. Should work.


Thank you, that really helped!
I should really know this :/
Original post by Bulletzone
I should really know this :/


Hey man, it's fine, I didn't either and I've got an exam in 3 weeks
Original post by Jack_Kavanagh
Hey man, it's fine, I didn't either and I've got an exam in 3 weeks


It's just the mechanisms and a few Inorganic equations which kill me :frown:
Original post by Bulletzone
It's just the mechanisms and a few Inorganic equations which kill me :frown:


Same here, man
Original post by Bulletzone
It's just the mechanisms and a few Inorganic equations which kill me :frown:


Yeah lol, just remember :
Electrophilic addition has to be with alkenes as electrophiles are electron deficient and the pi bond in alkenes provides a higher electron density.
Nucelophilic subsitution has to be with alkanes or anything with a polar bond as they need something positively charged to donate to.
Free radical sub is anything where uv light is given.
For as that's it unless you're doing A2.
Also, try to visualise what you have and what you need to get to. And work backwards. So for a carboxylic acid you either do reverse esterification (hydrolysis) or oxidation of an alcohol. then think, how do i get an alchol???? I'm not amazing at chemisty, but I try to break things down, hopefully helps.
Reply 8
Avatar for Sam00
Sam00
19
Wow, I knew this of the top of my head last year, now into the first year of a degree and would have to study it again to understand 😩
Original post by funky2722
Yeah lol, just remember :
Electrophilic addition has to be with alkenes as electrophiles are electron deficient and the pi bond in alkenes provides a higher electron density.
Nucelophilic subsitution has to be with alkanes or anything with a polar bond as they need something positively charged to donate to.
Free radical sub is anything where uv light is given.
For as that's it unless you're doing A2.
Also, try to visualise what you have and what you need to get to. And work backwards. So for a carboxylic acid you either do reverse esterification (hydrolysis) or oxidation of an alcohol. then think, how do i get an alchol???? I'm not amazing at chemisty, but I try to break things down, hopefully helps.


Elimination reaction we have to know.
Original post by Bulletzone
Elimination reaction we have to know.


Removal of water from an alchol? What's hard about that? It just H2SO4 at 180 degrees right, or is it 170?
Original post by funky2722
Removal of water from an alchol? What's hard about that? It just H2SO4 at 180 degrees right, or is it 170?


I dunno :frown:
Original post by Jack_Kavanagh
So, I'm trying to figure out how to convert ethane to ethanoic acid and the textbook hasn't helped really, anyone know the reagents and conditions?
Much thanks


Ummm, from pure memory...

- Add steam to the ethane to turn it into ethanol with a H3PO4 catalyst
- Use K2Cr2O7 to oxidise it to a carboxylic acid? (Under reflux, not distillation; distillation is to turn ethanol into ethanal)

I also really should know this lol but I think that might be right
Original post by Ash8991
Ummm, from pure memory...

- Add steam to the ethane to turn it into ethanol with a H3PO4 catalyst
- Use K2Cr2O7 to oxidise it to a carboxylic acid? (Under reflux, not distillation; distillation is to turn ethanol into ethanal)

I also really should know this lol but I think that might be right


Yeah I don't think would work as ethane is an alkane and adding water wouldn't do anything. It needs to be an alkene for this I thought, as the double bond breaks and then the extra OH atoms join?
Reply 14
Avatar for alow
alow
19
Original post by funky2722
Ethane= Hydrocarbon
Ethanoic acid = Carboxylic acid.

What i'd do is, convert the hydrocarbon into an alochol via 2 nucleophilic subsitutions. You can use NaBr, which would give you bromoethane.


Nope. Alkanes don't react via nucleophilic substitution.
Original post by alow
Nope. Alkanes don't react via nucleophilic substitution.


Just realised, the bond isn't polar. Hmm in that case, use free radical substituion using bromine radicals. Really sorry about that :frown:
Edit: This should give bromoethane and then you can use nucleophilc subsitution?
Just get a CGP revision guide and cram all the information before your AS exam, there is no application in AS Chemistry, just learn it
Original post by funky2722
Lol you couldn't be more wrong, there's barely anything to revise, it's all application.


I got an A last year with 2 weeks revision and quite a high one too, and I got 96% in my A2 chemistry mock and I've been revising since Feb so I can assure you there really isn't any application, you'll be fine

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