hydration of ethene (1 Viewer)

[table for 1]

quick Q

the hydration of ethene to from ethanol: using a dilute H2SO4 catalyst or phosphoric acid H3PO4?

i've got a diff answer from two sources. or can it be both, but more common is dilute H2SO4?

 

[nit]

Either H2SO4 or H3PO4 is suitable - the catalyst simply needs to be some mineral acid that protonates readily - ie any strong acid that doesn't interfere with the reaction. The acid is required in order for the mechanism of hydration of ethene to proceed. And it must be dilute to avoid absorption of H2O by the sulfuric acid, which, in accordance with Le Chatelier's principle, would drive the reaction to the left.

 

[table for 1]

ok, thank you =]

 

[physician]

quick Q

the hydration of ethene to from ethanol: using a dilute H2SO4 catalyst or phosphoric acid H3PO4?

i've got a diff answer from two sources. or can it be both, but more common is dilute H2SO4?

It can be both....

H2SO4 is used in laboratory preperation in small quantities
whilst... H3PO4 is used for industrial preperation in large quantities

 

[Dreamerish*~]

i always remembered it as

1. C₂H₄ + H₂O --> C₂H₅OH

there's H₂O on the left side of the equation... therefore the acid catalyst is dilute. (dilute acid has more H₂O in it )

2. C₂H₅OH --> C₂H₄ + H₂O

there's no H₂O on the left so the acid used is concentrated.

i don't know if this'll confuse anyone even more but it makes it easier for me

 

[lilkatie]

Hey that's a cool way to remember it, was just thinking about that this arvo

 

[~*HSC 4 life*~]

or just think that the 'ds' can't be together
ie
dehydration --> strong sulfuric acid

hydration --> dilute sulfuric acid

get me?

 

[Casmira]

I know its not how it works, but i remember it by thinking the concetrated being the strongest, decomposes ethanol into water and ethene and the other obviously does the opposite

 

[Dreamerish*~]

as long as it helps you remember xD

 

[thunderdax]

Should we also remember standard temp/pressure for hydration ie 330 C/60 atm?

 

[Dreamerish*~]

probably not...

 

[jarro_2783]

If the H2SO4 draws out water, and it's a catalyst to the hydration of ethene you would want less of it, ie. lower concentration. Because if the hydration is given by:

H2O + C2H4 --> C2H5OH (is that the formula of ethanol?)

If sulfuric acid draws out water, then it will take the water away from the left hand side of the rection, which will force the reaction to the left by Le Chatelier's principle. You don't want that, you want it to go right. So if H2SO4 is a catalyst, it would need to be less concentrated.

How do you do those subscript things?