PREPARATION OF A SIMPLE ESTER Unit 2 PPA 2

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PREPARATION OF A SIMPLE ESTER (Unit 2 PPA 2)
The aim of the experiment is to prepare the ester
ethyl ethanoate from ethanol and ethanoic acid.
(1) What kind of reaction occurs when an alcohol
and carboxylic acid react to form an ester?
(1) Condensation reaction.
(2) (a) The reactants and products are
highly flammable. This reduces the
risk of them catching fire. (b) (i) This acts
as a condenser and stops loss of
the volatile reactants and
product. (ii) This gives a higher yield
of ester by stopping the reverse
reaction.
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(3) At the end of the reaction the contents of
the boiling tube and poured into a beaker
containing sodium hydrogen-carbonate solution.
What two things would you see happening when
this occurs?
(3) Bubbles of carbon dioxide gas are given
off and an oily layer of the
(insoluble) ester appears on top of the
aqueous solution.
(4) A student reacted 2.30g of ethanol with an
excess of ethanoic acid. The mass of ethyl
ethanoate obtained was 2.86g. Using the
balanced equation for the reaction shown below,
calculate the percentage yield. C2H5OH
CH3COOH ?? C2H5OOCCH3 H2O
1 mol
1mol at 100 yield
46g 88g at 100 yield
2.3g 4.4g at 100 yield
Percentage yield 2.68 / 4.4 x 100 60.9