Unit 4b: Ethyl Ethanoate
Preparation of Ethyl Ethanoate
Ethyl ethanoate is the acetate ester formed between acetic acid and ethanol. It is a
colourless, flammable liquid with its most known characteristic being its sweet smell.
It is commonly used in perfumes, flavourings and pharmaceuticals, but is also used
in nail polish removers. [1]
Equipment:
● Goggles
● Round bottomed flasks (100㎤ and 250㎤)
● Receiver adapter
● Tap funnel
● Thermometer pocket
● Anti-bumping granules
● 50㎤ conical flask and bung
● Measuring cylinders
● 110℃ thermometer
● Separating funnel
● Gloves
● Condenser
● Funnel and filter paper
● Heating mantle
● Sodium carbonate (30%)
● Granular calcium chloride
● Conc. sulphuric acid, conc. ethanoic acid
● Ethanol
Method:
1. Mix 50㎤ ethanol and 50㎤ glacial ethanoic acid in a 250㎤ round - bottomed
flask.
2. Slowly add 10㎤ of cooling concentrated sulphuric acid.
3. Ensure the mixture is homogeneous then fit the flask with a reflux water
condenser and boil very gently for 10 minutes.
4. Rearrange the condenser for distillation and distil off about 2/3rds of the
mixture.
5. Transfer the distillate to a separating funnel and add 25㎤ of 30% sodium
carbonate solution. Stopper the funnel, invert it and shake, opening the tap
from time to time.
6. Allow the two layers to separate and carefully run off and discard the lower
layer.
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, Btec Applied Science
Unit 4b: Ethyl Ethanoate
7. Prepare a solution of 25g calcium chloride in 25㎤ water. Add to the crude
ethyl ethanoate in the funnel and shake vigorously. Allow the mixture to
separate and run off the lower aqueous layer.
8. Run the ethyl ethanoate into a small conical flask and add a few lumps of
granular anhydrous calcium chloride and shake.
9. Decant the liquid into a clean dry 100㎤ round - bottomed flask, add anti
bumping granules and arrange for distillation. The flask should be in a cold
water bath that is gradually heated. Discard the fraction at 35 - 40℃. Collect
the fraction that boils between 74℃ and 79℃.
[figure 1: reflux distillation]
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