c
AqA
A-level
CHEMISTRY
Paper 3
June 2023
pg. 1
, 2
Do not write
outside the
Section A box
Answer all questions in this
section.
0 ethanoate
Ethyl 1 can be made by reacting ethanol with ethanoic acid in the presence of
concentrated sulfuric acid.
Method
1. A mixture of ethanol, ethanoic acid, and concentrated sulfuric
acid, with anti-bumping granules, is heated under reflux for 10
minutes.
2. The apparatus is rearranged for distillation.
3. The mixture is heated to collect the liquid that distils between 70 and 85 C
4. The distillate is placed in a separating funnel. Aqueous sodium
carbonate is added, and a stopper is placed in the funnel. The
mixture is shaken, releasing pressure as necessary.
5. The lower aqueous layer is removed and the upper organic layer is
placed in a small conical flask.
6. Anhydrous calcium chloride is added to the sample in the conical
flask. The flask is shaken well and left for a few minutes.
7. The liquid from the flask is redistilled and the distillate is
collected between 74 and 79 C
0 1 .1 State the role of concentrated sulfuric acid in this reaction.
[1 mark]
0 1 .2 The reaction mixture is flammable.
Suggest how the reaction mixture should be heated in step 1.
[1 mark]
*02
IB/M/
* Jun23/7405/3
, 3
Do not write
outside the
0 1 .3 Figure 1 shows how a student set up the apparatus for reflux box
in step 1. You should assume that the apparatus is clamped
correctly.
Figure 1
Identify two mistakes the student made in setting up the
apparatus. State the problem caused by each mistake.
[4 marks]
Mistake 1
Problem caused
Mistake 2
Problem caused
Turn over ►
*03
IB/M/
* Jun23/7405/3
, 4
Do not write
outside the
0 1 .4 State why sodium carbonate is added to the distillate in box
step 4.
Explain why there is a build-up of pressure in the [2
separating funnel. marks]
0 1
.5 Give a reason why two layers form in the separating funnel.
Suggest why ethyl ethanoate forms the upper layer.
[2 marks]
Reason
Suggestion
0 1 .6 State why anhydrous calcium chloride is added in step 6.
[1 mark]
*04
IB/M/
* Jun23/7405/3
AqA
A-level
CHEMISTRY
Paper 3
June 2023
pg. 1
, 2
Do not write
outside the
Section A box
Answer all questions in this
section.
0 ethanoate
Ethyl 1 can be made by reacting ethanol with ethanoic acid in the presence of
concentrated sulfuric acid.
Method
1. A mixture of ethanol, ethanoic acid, and concentrated sulfuric
acid, with anti-bumping granules, is heated under reflux for 10
minutes.
2. The apparatus is rearranged for distillation.
3. The mixture is heated to collect the liquid that distils between 70 and 85 C
4. The distillate is placed in a separating funnel. Aqueous sodium
carbonate is added, and a stopper is placed in the funnel. The
mixture is shaken, releasing pressure as necessary.
5. The lower aqueous layer is removed and the upper organic layer is
placed in a small conical flask.
6. Anhydrous calcium chloride is added to the sample in the conical
flask. The flask is shaken well and left for a few minutes.
7. The liquid from the flask is redistilled and the distillate is
collected between 74 and 79 C
0 1 .1 State the role of concentrated sulfuric acid in this reaction.
[1 mark]
0 1 .2 The reaction mixture is flammable.
Suggest how the reaction mixture should be heated in step 1.
[1 mark]
*02
IB/M/
* Jun23/7405/3
, 3
Do not write
outside the
0 1 .3 Figure 1 shows how a student set up the apparatus for reflux box
in step 1. You should assume that the apparatus is clamped
correctly.
Figure 1
Identify two mistakes the student made in setting up the
apparatus. State the problem caused by each mistake.
[4 marks]
Mistake 1
Problem caused
Mistake 2
Problem caused
Turn over ►
*03
IB/M/
* Jun23/7405/3
, 4
Do not write
outside the
0 1 .4 State why sodium carbonate is added to the distillate in box
step 4.
Explain why there is a build-up of pressure in the [2
separating funnel. marks]
0 1
.5 Give a reason why two layers form in the separating funnel.
Suggest why ethyl ethanoate forms the upper layer.
[2 marks]
Reason
Suggestion
0 1 .6 State why anhydrous calcium chloride is added in step 6.
[1 mark]
*04
IB/M/
* Jun23/7405/3
