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Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Unit

Organic Chemistry

785 practice questions

Start practising (785 questions)

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Practice questions

731–740 of 785

  1. Question 731

    3 marks · Normal

    A polyester is formed from 10 molecules of butane-1,4-diol (HOCH2CH2CH2CH2OH) and 10 molecules of hexane-1,6-dioic acid (HOOCCH2CH2CH2CH2CH2COOH). Calculate the number of water molecules produced when these monomers react completely to form one long polyester chain.

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  2. Question 732

    3 marks · Normal

    Explain why a polyester molecule contains ester groups and describe how these groups are formed during polymerisation.

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  3. Question 733

    4 marks · Normal

    The table shows the properties of two polyesters.

    Properties of Polyesters A and B
    PolyesterMonomers UsedMelting Point / CTensile Strength
    Aethane-1,2-diol + benzene-1,4-dicarboxylic acid258High
    Bpropane-1,3-diol + benzene-1,4-dicarboxylic acid140Medium
    (a)

    State one similarity and one difference in the monomers used to make Polyesters A and B.

    [2 marks]
    (b)

    Using the data in the table, suggest a reason for the difference in melting point between Polyester A and Polyester B.

    [2 marks]
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  4. Question 734

    1 mark · Normal

    Which of the following statements about polyesters is correct?

    1. A.Polyesters are formed by addition polymerisation of alkenes.
    2. B.Polyesters are made from diols and dicarboxylic acids by condensation polymerisation.
    3. C.Only one type of monomer is needed to form a polyester.
    4. D.No water is lost when making a polyester.
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  5. Question 735

    2 marks · Normal

    Give one everyday use of polyesters and state one property of polyesters that makes them suitable for this use.

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  6. Question 736

    4 marks · Normal

    (a)

    Write a balanced chemical equation using structural formulae for the reaction between ethane-1,2-diol (HOCH2CH2OH) and butane-1,4-dioic acid (HOOCCH2CH2CH2COOH) to form a polyester and water.

    [2 marks]
    (b)

    Explain why the product formed is called a polyester.

    [2 marks]
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  7. Question 737

    2 marks · Hard

    State the names of the two functional groups present in the monomers that react together to form a polyester. For each group, state the name of the organic compound type it is found on (use "diol" or "dicarboxylic acid").

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  8. Question 738

    5 marks · Hard

    The polymerisation of propane-1,3-diol and benzene-1,4-dicarboxylic acid forms a polyester. Propane-1,3-diol has the formula and benzene-1,4-dicarboxylic acid has the formula .

    (a)

    Draw the structural formula of both monomers.

    [2 marks]
    (b)

    Explain why water is eliminated when the two monomers react to form the polyester.

    [1 mark]
    (c)

    State one everyday use of polyesters produced in this way.

    [1 mark]
    (d)

    Name the type of polymerisation that occurs and give one reason for this classification.

    [1 mark]
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  9. Question 739

    2 marks · Hard

    Describe the main structural features that all polyesters have in common. Suggest why these features are important for the properties and uses of polyesters.

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  10. Question 740

    1 mark · Easy

    Draw the structure of the repeat unit of polylactic acid (PLA) formed from lactic acid monomers.

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