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lozabella

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we did a prac making ethyl ethanoate and i need to compare the physical properties of components of the mixture which allow separation by a) distillation and b) the use of a separating funnel....n im kinda confused as to what exactly i'm supposed to be writing...any help would be awesome please:D
 

illin

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ethanol + ethanoic acid = Ethyl ethanoate + water

standard equation with sulfuric acid used as a catalyst.
a) distillation can be used to separate ethanol and ethanoic acid based upon their respective bioling pts
polar bonds occur between two atoms with a great difference in their electronegativity.
An Alkanoic acid has 3 polar bonds, alkanol has 2. Therefore bonds in the alkanoic acid are stronger than in then alkanol. Alkonic acids have twice as much Hydrogen Bonding as in Alkanols (draw a diagram). Therefore melting and Boiling points of the alkanioc acids are greater than those of alkanols.

b) Separating funnel

Both are immiscible and therefore it is possible to separate them due to this.

The sulfuric acid used as the catalyst absorbs the water, as the reaction is a condensation reaction, and the water condenses out.
 
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mitochondria

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To make an ester you need an alcohol and an acid (you probably already know that :p) and in your case (ethyl ethanoate) the alcohol is CH3CH2OH and the acid is CH2COOH.

CH3CH2OH + CH3COOH -----> CH3CH2O-COCH3 + H2O

You would have used concentrated H2SO4 to absorb the water.. to simplify things a bit, let's assume the reaction proceeds all the way to the right hand side of the equation.

The mixture you get at the end, therefore, will be a mixture of ethyl ethanoate and water, which have different physical properties such as *big hint* density and boiling point - and these are what you'll be comparing and writing about :)

So.. do you know what you'll be doing now? Come back if you need more help :) Hope that helps!
 

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