SubjectCover

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

Introduction to Organic Chemistry

185 practice questions

Topics covered

Practice questions

111–120 of 185

  1. Question 111

    2 marks · Hard

    A hydrocarbon molecule is named 4-methylhexane.

    Determine from which end of the main chain numbering should start to give the position of the methyl side chain, and explain your choice.

    Answer and see the solution →
  2. Question 112

    5 marks · Hard

    The following hydrocarbon is shown using its skeletal formula:

    Geometry diagram with points C1, C2, C3, C4, C5, M3A
    Skeletal formula of a branched alkane.
    (a)

    State the length (number of carbon atoms) in the longest chain of the molecule.

    [1 mark]
    (b)

    Name the side chain and state the carbon atom number on which it is attached.

    [2 marks]
    (c)

    Write the complete IUPAC name for this molecule.

    [2 marks]
    Answer and see the solution →
  3. Question 113

    2 marks · Hard

    Give the coding (name) for each of the following side chains found in organic molecules:

    Side chain structural formulaCode (name)
    \ce{CH_3}-
    \ce{CH_3CH_2}-
    Answer and see the solution →
  4. Question 114

    1 mark · Easy

    State what structural isomers have in common.

    Answer and see the solution →
  5. Question 115

    3 marks · Easy

    (a)

    State the difference between a straight-chain alkane and a branched-chain alkane.

    [1 mark]
    (b)

    Draw the displayed formula for a branched structural isomer of C5H12.

    [2 marks]
    Answer and see the solution →
  6. Question 116

    2 marks · Easy

    Propane (C3H8) has no structural isomers. Predict and state the number of structural isomers for butane (C4H10).

    Answer and see the solution →
  7. Question 117

    2 marks · Easy

    Explain why it is not possible to convert one structural isomer of pentane directly into another simply by rotating bonds.

    Answer and see the solution →
  8. Question 118

    3 marks · Easy

    The table shows the number of isomers for selected alkanes.

    AlkaneMolecular formulaNumber of isomers
    MethaneCH41
    EthaneC2H61
    PropaneC3H81
    PentaneC5H123
    (a)

    Describe the trend in the number of isomers as the number of carbon atoms increases.

    [1 mark]
    (b)

    Suggest why methane, ethane, and propane each have only one isomer.

    [2 marks]
    Answer and see the solution →
  9. Question 119

    1 mark · Easy

    Give the molecular formula for the straight-chain alkane with five carbon atoms.

    Answer and see the solution →
  10. Question 120

    3 marks · Easy

    (a)

    State the molecular formula for hexane.

    [1 mark]
    (b)

    Explain what makes two different hexane molecules structural isomers.

    [2 marks]
    Answer and see the solution →