Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Section
Structural isomerism in the alkanes
19 practice questions
Practice questions
1–8 of 8 · Easy
Question 1
1 mark · Easy
Answer and see the solution →State what structural isomers have in common.
Question 2
3 marks · Easy
Answer and see the solution →(a)[1 mark]State the difference between a straight-chain alkane and a branched-chain alkane.
(b)[2 marks]Draw the displayed formula for a branched structural isomer of C5H12.
Question 3
2 marks · Easy
Answer and see the solution →Propane (C3H8) has no structural isomers. Predict and state the number of structural isomers for butane (C4H10).
Question 4
2 marks · Easy
Answer and see the solution →Explain why it is not possible to convert one structural isomer of pentane directly into another simply by rotating bonds.
Question 5
3 marks · Easy
Answer and see the solution →The table shows the number of isomers for selected alkanes.
Alkane Molecular formula Number of isomers Methane CH4 1 Ethane C2H6 1 Propane C3H8 1 Pentane C5H12 3 (a)[1 mark]Describe the trend in the number of isomers as the number of carbon atoms increases.
(b)[2 marks]Suggest why methane, ethane, and propane each have only one isomer.
Question 6
1 mark · Easy
Answer and see the solution →Give the molecular formula for the straight-chain alkane with five carbon atoms.
Question 7
3 marks · Easy
Answer and see the solution →(a)[1 mark]State the molecular formula for hexane.
(b)[2 marks]Explain what makes two different hexane molecules structural isomers.
Question 8
2 marks · Easy
Answer and see the solution →How many carbon atoms are present in the alkane with the molecular formula C8H18?