BTEC Level 3 National Foundation Diploma in Applied
Qualification
Science
Unit 4: Laboratory Techniques and their Application
Unit number and title
B: Explore the manufacturing techniques and testing
Learning aim
methods for an organic liquid
P3 Correctly prepare and test the purity of an organic liquid and draw conclusions
M2 Demonstrate skilful application of techniques in preparing and testing the purity
of an organic liquid and draw detailed conclusions.
1. Firstly set up the apparatus, making sure the glassware is
set up correctly, to heat up the mixture. To create the
mixture, add 10cm3 of ethanol and 10cm3 glacial ethanoic
acid into a 100cm3 round bottomed flask, ensuring that the
ethanoic acid is kept in the fume cupboard for health and
safety, for example, the fumes produced can cause lung
and eye damage. Then swirl the mixture. Whilst swirling
the mixture, carefully add 5cm3 concentrated sulphuric
acid slowly, because the reaction can get too vigorous if
the acid is added too quickly.
2. Add some anti-bumping granules. Anti- bumping granules are used to ensure that
large gas bubbles aren’t formed, this is by providing nucleation sites for small
bubbles to be able to develop. A nucleation site is where small bubbles can be
formed to prevent rapid boiling of liquids during a reaction.
3. Next, heat up the mixture for 10 minutes, to do this, use a heating mantle or a hot
plate, not a bunsen burner because the reactions may be highly flammable, due to
the alcohols, therefore, there are no naked flames, and fit the pear shaped flask
with a reflux condenser, this condenser will stop any vapour from escaping. When
the reflux has finished heating, turn off the heating mantle, and allow the mixture to
cool. This mixture will give an impure ester so appropriate separation techniques
need to be used to purify it. Moreover, it is important to not heat up the mixture for
too long, this is because it can burn and give out fumes, this causes the eyes to
water and hurt.
4. Then, set up the apparatus for distillation with a thermometer and use the heating
mantle to distil off around two thirds of the mixture into a small conical flask. This
will be the product of ethyl ethanoate.This will remove any impurities that are in the
ester, such as alcohol and sulfuric acid.
5. Next, pour the distillate into a separating funnel and wash it using 20cm3 saturated
aqueous sodium carbonate solution. Also, invert the funnel at intervals and open
the tap to release pressure due to the carbon dioxide released at this stage,
Ensuring the mixture has enough time to separate fully.
1
BTEC Assignment Brief v1.0
BTEC Internal Assessment QDAM January 2015
, 6. Discard the lower aqueous layer and decant the remaining liquid into a conical
flask.
7. Next, shake the impure ester in the funnel with a solution made by dissolving 10g
hydrated calcium chloride in 10cm3 water. Then, separate and discard the lower
layer before decanting the remaining liquid into conical flask.
8. In addition, it is important to run the ethyl ethanoate into a small conical flask and
stand the ester over a few lumps of anhydrous calcium chloride until the liquid
clears, which will take around 20 minutes.
9. The liquid then needs to be filtered or decanted, and distilled in clean dry Quickfit
and collect the fraction boiling over in the range 74-79 celsius.
10. Then, carry out a boiling point test of the sample, and then test the purity of the
sample of ethyl ethanoate using an Infrared spectrometer.
There are some risks of this experiment, such as some of the measurements may be
inaccurate. Also, the wrong filter may be used, therefore some of the mixtures that
should’ve gone are still in therefore this product might not be correct.
Boiling point of the Ethyl Ethanoate sample (o.C) 80
Overall, this experiment didn’t go well, the boiling point for my ethyl ethanoate was 80
degrees celsius, therefore, this suggests that my sample was impure, because a pure
sample of ethyl ethanoate has a boiling point of 77.1 degrees celsius. In addition, the
impurities in a liquid will cause the boiling point to rise, which suggests the reason for my
sample being 80 degrees celsius. spectrometer, to test the purity of the liquid.
This is the standard IR spectrum for pure ethyl
ethanoate. When ethyl ethanoate is analysed in
the IR spectrometer an image is produced. This
can be analysed to see if the sample is pure. If the
sample is pure it would only have the troughs that
you would expect from this compound, (as shown
in the image with the blue lines to the left). Also,
the presence of the troughs at 3000 and the nature
of the fingerprint region shows that a pure sample
has been made.
However, if the sample is impure it would contain
troughs that shouldn’t be there, (as shown in the
image with the red lines to the left). Also, shown in
the graph, there are extra troughs on the spectra
that show that some impurities are still in the
compound. For example, the first small trough is
caused by the impurities, the second large trough
shows the C-H bond in the product, then the third
large trough shows the C=O bond in the product, and finally the rest of the spectra shows
that more than one compound is present ie the sample is not pure and contains other
compounds as well as ethyl ethanoate.
2
BTEC Assignment Brief v1.0
BTEC Internal Assessment QDAM January 2015
Qualification
Science
Unit 4: Laboratory Techniques and their Application
Unit number and title
B: Explore the manufacturing techniques and testing
Learning aim
methods for an organic liquid
P3 Correctly prepare and test the purity of an organic liquid and draw conclusions
M2 Demonstrate skilful application of techniques in preparing and testing the purity
of an organic liquid and draw detailed conclusions.
1. Firstly set up the apparatus, making sure the glassware is
set up correctly, to heat up the mixture. To create the
mixture, add 10cm3 of ethanol and 10cm3 glacial ethanoic
acid into a 100cm3 round bottomed flask, ensuring that the
ethanoic acid is kept in the fume cupboard for health and
safety, for example, the fumes produced can cause lung
and eye damage. Then swirl the mixture. Whilst swirling
the mixture, carefully add 5cm3 concentrated sulphuric
acid slowly, because the reaction can get too vigorous if
the acid is added too quickly.
2. Add some anti-bumping granules. Anti- bumping granules are used to ensure that
large gas bubbles aren’t formed, this is by providing nucleation sites for small
bubbles to be able to develop. A nucleation site is where small bubbles can be
formed to prevent rapid boiling of liquids during a reaction.
3. Next, heat up the mixture for 10 minutes, to do this, use a heating mantle or a hot
plate, not a bunsen burner because the reactions may be highly flammable, due to
the alcohols, therefore, there are no naked flames, and fit the pear shaped flask
with a reflux condenser, this condenser will stop any vapour from escaping. When
the reflux has finished heating, turn off the heating mantle, and allow the mixture to
cool. This mixture will give an impure ester so appropriate separation techniques
need to be used to purify it. Moreover, it is important to not heat up the mixture for
too long, this is because it can burn and give out fumes, this causes the eyes to
water and hurt.
4. Then, set up the apparatus for distillation with a thermometer and use the heating
mantle to distil off around two thirds of the mixture into a small conical flask. This
will be the product of ethyl ethanoate.This will remove any impurities that are in the
ester, such as alcohol and sulfuric acid.
5. Next, pour the distillate into a separating funnel and wash it using 20cm3 saturated
aqueous sodium carbonate solution. Also, invert the funnel at intervals and open
the tap to release pressure due to the carbon dioxide released at this stage,
Ensuring the mixture has enough time to separate fully.
1
BTEC Assignment Brief v1.0
BTEC Internal Assessment QDAM January 2015
, 6. Discard the lower aqueous layer and decant the remaining liquid into a conical
flask.
7. Next, shake the impure ester in the funnel with a solution made by dissolving 10g
hydrated calcium chloride in 10cm3 water. Then, separate and discard the lower
layer before decanting the remaining liquid into conical flask.
8. In addition, it is important to run the ethyl ethanoate into a small conical flask and
stand the ester over a few lumps of anhydrous calcium chloride until the liquid
clears, which will take around 20 minutes.
9. The liquid then needs to be filtered or decanted, and distilled in clean dry Quickfit
and collect the fraction boiling over in the range 74-79 celsius.
10. Then, carry out a boiling point test of the sample, and then test the purity of the
sample of ethyl ethanoate using an Infrared spectrometer.
There are some risks of this experiment, such as some of the measurements may be
inaccurate. Also, the wrong filter may be used, therefore some of the mixtures that
should’ve gone are still in therefore this product might not be correct.
Boiling point of the Ethyl Ethanoate sample (o.C) 80
Overall, this experiment didn’t go well, the boiling point for my ethyl ethanoate was 80
degrees celsius, therefore, this suggests that my sample was impure, because a pure
sample of ethyl ethanoate has a boiling point of 77.1 degrees celsius. In addition, the
impurities in a liquid will cause the boiling point to rise, which suggests the reason for my
sample being 80 degrees celsius. spectrometer, to test the purity of the liquid.
This is the standard IR spectrum for pure ethyl
ethanoate. When ethyl ethanoate is analysed in
the IR spectrometer an image is produced. This
can be analysed to see if the sample is pure. If the
sample is pure it would only have the troughs that
you would expect from this compound, (as shown
in the image with the blue lines to the left). Also,
the presence of the troughs at 3000 and the nature
of the fingerprint region shows that a pure sample
has been made.
However, if the sample is impure it would contain
troughs that shouldn’t be there, (as shown in the
image with the red lines to the left). Also, shown in
the graph, there are extra troughs on the spectra
that show that some impurities are still in the
compound. For example, the first small trough is
caused by the impurities, the second large trough
shows the C-H bond in the product, then the third
large trough shows the C=O bond in the product, and finally the rest of the spectra shows
that more than one compound is present ie the sample is not pure and contains other
compounds as well as ethyl ethanoate.
2
BTEC Assignment Brief v1.0
BTEC Internal Assessment QDAM January 2015
