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Danielisew
Q) State one of the advantages of reacting ethanoyl chloride with ethanol to make an ester rather than reacting ethanoic acid with ethanol.

I was thinking maybe with an acyl chloride, the chain length would increase but it seems to increase the same for both?


the by-product (HCl) is gaseous and more easily lost..
Reply 2
HCL give off can be collected and sold or recycled into another process?
Reply 3
also its more reactive and hence easier to carry out and more efficient
Reply 4
On an industrial scale, HCl is a pain to get rid off as it is corrosive.
Reply 5
I believe that the Ethanoyl Chloride reaction gives a better yield and happens faster.
Reply 6
Thanks everyone :smile:
Faster reaction, higher yield and if the HCl is siphoned off you get a pure product and a byproduct that can be used for other industrial processes.
Reply 8
It goes to completion
Reply 9
Most important: cheapest (however the fact that it goes to completion is rather important).
Reply 10
surely acetic acid is cheaper? Ethanoyl chloride is alot more fun to handle though, forms HCl with contact with water, like when it touches your skin and the air :smile:.
Reply 11
tomsey11
surely acetic acid is cheaper? Ethanoyl chloride is alot more fun to handle though, forms HCl with contact with water, like when it touches your skin and the air :smile:.


To set up the reaction with an alcohol and carboxylic for the same yield you would obtain with the ethanoyl chloride ... well that is gonna be costly.

:shifty: stay away from me if you are holding acid!!

Only kidding.
Reply 12
DeanK2
To set up the reaction with an alcohol and carboxylic for the same yield you would obtain with the ethanoyl chloride ... well that is gonna be costly.


I'm confused :frown:. Are you saying it would be more expensive to achieve a decent yield with ethanoic acid? That depends on the difference in the two prices and yields...This may be totally over-analysing the original question.. :wink:
They are basically looking for HCl as the answer. It is agas and hence easier to remove which in turn pulls the reaction to the right hand side. With the acid you get an equilibrium, i.e. it does not go to completion without further action..
Reply 14
charco
They are basically looking for HCl as the answer. It is agas and hence easier to remove which in turn pulls the reaction to the right hand side. With the acid you get an equilibrium, i.e. it does not go to completion without further action..


Only one reaction is reversible - removing the HCl does not affect the rate as it is not a homogeneous mixture, and nor is the reaction reversible.
DeanK2
Only one reaction is reversible - removing the HCl does not affect the rate as it is not a homogeneous mixture, and nor is the reaction reversible.


The reason the reaction is not reversible is the loss of HCl - that is the point I was making!
Reply 16
charco
They are basically looking for HCl as the answer.

Not really, as you could quite easily consider production of HCl gas a bad thing.
Dynasty
Not really, as you could quite easily consider production of HCl gas a bad thing.

Indeed, the advantage of using ethanoic anhydride instead of chloride is that no HCl is produced.
Reply 18
its because the HCl produced is a gas, so the products dont need to be distilled later. Also, because its a one was reaction, you get the product that you want. In the other one, beacuse its reversible, youll have to distill the products to separate them.
Reply 19
Revd. Mike
Indeed, the advantage of using ethanoic anhydride instead of chloride is that no HCl is produced.


???

Why mention this?

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