A-level
CHEMISTRY
Paper 2 Organic and Physical Chemistry
Time allowed: 2 hours
Materials For Examiner’s Use
For this paper you must have:
• the Periodic Table/Data Booklet, provided as an insert (enclosed)
• a ruler with millimetre measurements Question Mark
• a scientific calculator, which you are expected to use where appropriate.
1
Instructions
• Use black ink or black ball-point pen. 2
3
4
5
6
7
8
9
10
TOTAL
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Please write clearly in block capitals.
Centre number Candidate number
Surname
Forename(s)
Candidate signature
I declare this is my own work.
• Fill in the boxes at the top of this page.
• Answer all questions.
• You must answer the questions in the spaces provided. Do not write outside the box around each
page or on blank pages.
• If you need extra space for your answer(s), use the lined pages at the end of this book. Write the
question number against your answer(s).
• All working must be shown.
• Do all rough work in this book. Cross through any work you do not want to be marked.
Information
• The marks for questions are shown in brackets.
• The maximum mark for this paper is 105.
*Jun217405201* IB/M/Jun21/E12 7405/2
Answer all questions in the spaces provided.
Coconut oil contains a triester with three identical R groups.
0 1 This triester reacts with potassium hydroxide.
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0 1 .1
Complete the equation by drawing the structure of the other product of this reaction in
the box.
Name the type of compound shown by the formula RCOOK
Give one use for this type of compound.
[3 marks]
Type of compound
Use
0 1 .2 The triester in coconut oil has a relative molecular mass, Mr = 638.0
In the equation shown at the start of Question 01, R represents an alkyl group that can
be written as CH3(CH2)n
Deduce the value of n in CH3(CH2)n Show
your working.
[3 marks]
n
*02*
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A 1.450 g sample of coconut oil is heated with 0.421 g of KOH in aqueous ethanol until
0 1 .3 all of the triester is hydrolysed.
The mixture is cooled.
The remaining KOH is neutralised by exactly 15.65 cm3 of 0.100 mol dm–3 HCl
Calculate the percentage by mass of the triester (Mr = 638.0) in the coconut oil.
[6 marks]
Percentage by mass
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*03*
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1 4 Suggest why aqueous ethanol is a suitable solvent when heating the coconut oil
with KOH.
Give a safety precaution used when heating the mixture.
Justify your choice.
[3 marks]
Reason
Safety precaution
Justification
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*04*
0 2
This question is about fuels.
0 2 .1 The petrol fraction obtained from crude oil can be used as fuel in cars.
State the meaning of fraction, as used in the term petrol fraction.
[1 mark]
15
0 2 .2
Hexadecane (C16H34) can be cracked at high temperature to form petrol.
Complete the equation to show the cracking of one molecule of hexadecane to form
hexane and cyclopentane only.
Give the name of a catalyst used in this cracking reaction.
[3 marks]
Catalyst
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Carbon dioxide is formed when petrol is burned.
0 2 .3 Carbon dioxide acts as a greenhouse gas when it absorbs infrared radiation.
Give a reason why carbon dioxide absorbs infrared radiation.
[1 mark]
Question 2 continues on the next page
*05*
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2 4 Compound Z (HOCH2CH2NH2) can be used to remove carbon dioxide from the
mixture of waste gases produced in some power stations.
Figure 1 shows part of a suggested mechanism for the reaction of Z with
carbon dioxide.
Figure 1
Draw two curly arrows to complete the mechanism in Figure 1.
Name compound Z (HOCH2CH2NH2)
Deduce the role of Z in step 2 of the mechanism.
[4 marks]
Name
Role
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CHEMISTRY
Paper 2 Organic and Physical Chemistry
Time allowed: 2 hours
Materials For Examiner’s Use
For this paper you must have:
• the Periodic Table/Data Booklet, provided as an insert (enclosed)
• a ruler with millimetre measurements Question Mark
• a scientific calculator, which you are expected to use where appropriate.
1
Instructions
• Use black ink or black ball-point pen. 2
3
4
5
6
7
8
9
10
TOTAL
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2
Do not write
outside the
box
Please write clearly in block capitals.
Centre number Candidate number
Surname
Forename(s)
Candidate signature
I declare this is my own work.
• Fill in the boxes at the top of this page.
• Answer all questions.
• You must answer the questions in the spaces provided. Do not write outside the box around each
page or on blank pages.
• If you need extra space for your answer(s), use the lined pages at the end of this book. Write the
question number against your answer(s).
• All working must be shown.
• Do all rough work in this book. Cross through any work you do not want to be marked.
Information
• The marks for questions are shown in brackets.
• The maximum mark for this paper is 105.
*Jun217405201* IB/M/Jun21/E12 7405/2
Answer all questions in the spaces provided.
Coconut oil contains a triester with three identical R groups.
0 1 This triester reacts with potassium hydroxide.
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3
Do not write
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0 1 .1
Complete the equation by drawing the structure of the other product of this reaction in
the box.
Name the type of compound shown by the formula RCOOK
Give one use for this type of compound.
[3 marks]
Type of compound
Use
0 1 .2 The triester in coconut oil has a relative molecular mass, Mr = 638.0
In the equation shown at the start of Question 01, R represents an alkyl group that can
be written as CH3(CH2)n
Deduce the value of n in CH3(CH2)n Show
your working.
[3 marks]
n
*02*
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A 1.450 g sample of coconut oil is heated with 0.421 g of KOH in aqueous ethanol until
0 1 .3 all of the triester is hydrolysed.
The mixture is cooled.
The remaining KOH is neutralised by exactly 15.65 cm3 of 0.100 mol dm–3 HCl
Calculate the percentage by mass of the triester (Mr = 638.0) in the coconut oil.
[6 marks]
Percentage by mass
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*03*
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1 4 Suggest why aqueous ethanol is a suitable solvent when heating the coconut oil
with KOH.
Give a safety precaution used when heating the mixture.
Justify your choice.
[3 marks]
Reason
Safety precaution
Justification
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*04*
0 2
This question is about fuels.
0 2 .1 The petrol fraction obtained from crude oil can be used as fuel in cars.
State the meaning of fraction, as used in the term petrol fraction.
[1 mark]
15
0 2 .2
Hexadecane (C16H34) can be cracked at high temperature to form petrol.
Complete the equation to show the cracking of one molecule of hexadecane to form
hexane and cyclopentane only.
Give the name of a catalyst used in this cracking reaction.
[3 marks]
Catalyst
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Carbon dioxide is formed when petrol is burned.
0 2 .3 Carbon dioxide acts as a greenhouse gas when it absorbs infrared radiation.
Give a reason why carbon dioxide absorbs infrared radiation.
[1 mark]
Question 2 continues on the next page
*05*
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2 4 Compound Z (HOCH2CH2NH2) can be used to remove carbon dioxide from the
mixture of waste gases produced in some power stations.
Figure 1 shows part of a suggested mechanism for the reaction of Z with
carbon dioxide.
Figure 1
Draw two curly arrows to complete the mechanism in Figure 1.
Name compound Z (HOCH2CH2NH2)
Deduce the role of Z in step 2 of the mechanism.
[4 marks]
Name
Role
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