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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) Question Mark
• a ruler with millimetre measurements
1
• a scientific calculator, which you are expected to use where appropriate.
2
Instructions 3
• Use black ink or black ball-point pen. 4
• Fill in the boxes at the top of this page.
5
• Answer all questions.
• You must answer the questions in the spaces provided. Do not write outside 6
the box around each page or on blank pages. 7
• If you need extra space for your answer(s), use the lined pages at the end of 8
this book. Write the question number against your answer(s).
• All working must be shown. 9
• Do all rough work in this book. Cross through any work you do not want to 10
be marked.
TOTAL
Information
• The marks for questions are shown in brackets.
• The maximum mark for this paper is 105.
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, 2
Do not write
outside the
Answer all questions in the spaces provided. box
0 1 Coconut oil contains a triester with three identical R groups.
This triester reacts with potassium hydroxide.
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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, 3
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outside the
0 1 . 3 A 1.450 g sample of coconut oil is heated with 0.421 g of KOH in aqueous ethanol box
until 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
Turn over ►
*03*
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, 4
Do not write
outside the
0 1 . 4 Suggest why aqueous ethanol is a suitable solvent when heating the coconut oil box
with KOH.
Give a safety precaution used when heating the mixture.
Justify your choice.
[3 marks]
Reason
Safety precaution
Justification
15
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