Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Unit
Organic Chemistry
785 practice questions
Topics covered
Practice questions
51–60 of 335 · Normal
Question 51
3 marks · Normal
Answer and see the solution →A hydrocarbon has the molecular formula C6H14. How many structural isomers are possible for C6H14? Show your reasoning.
Question 52
3 marks · Normal
Answer and see the solution →Explain how you would decide whether two structures for C5H12 drawn below are isomers or not.
Structure 1: CH3–CH2–CH2–CH2–CH3 Structure 2: CH3–CH(CH3)–CH2–CH3
Question 53
4 marks · Normal
Answer and see the solution →The following table gives the molecular formulae and numbers of structural isomers possible for members of the alkane series:
Alkane Molecular formula Number of isomers Methane CH4 1 Ethane C2H6 1 Propane C3H8 1 Butane C4H10 2 Pentane C5H12 3 Hexane C6H14 ? (a)[1 mark]Compare the number of isomers as the number of carbon atoms increases from C4H10 to C6H14.
(b)[2 marks]Explain why the number of structural isomers increases as you go from C4H10 to C6H14.
(c)[1 mark]Use the data to predict the number of isomers for C6H14.
Question 54
1 mark · Normal
Answer and check →Which statement is true about structural isomers?
- A.They have the same molecular and structural formulae.
- B.They have the same atoms joined in a different order.
- C.They are different elements with the same mass number.
- D.They all have a straight chain structure.
Question 55
2 marks · Normal
Answer and see the solution →State one difference and one similarity between structural isomers.
Question 56
4 marks · Normal
Answer and see the solution →Heptane (C7H16) is an alkane. Answer the following about its isomers.
(a)[1 mark]Explain why heptane can form structural isomers.
(b)[2 marks]Draw the skeletal formula of two different isomers of C7H16.
(c)[1 mark]State one feature that all isomers of C7H16 share.
Question 57
2 marks · Normal
Answer and see the solution →State the functional group present in all alcohols. Give its displayed formula.
Question 58
3 marks · Normal
Answer and see the solution →Explain why methanol and ethanol are both classified as alcohols, even though their formulas are different. Include reference to naming rules in your answer.
Question 59
4 marks · Normal
Answer and see the solution →The table below gives the molecular formula of several organic compounds. Complete the table by stating whether each compound is an alcohol and, if so, writing its functional group.
Compound Molecular formula Alcohol (Yes/No)? Functional group (if any) Methanol CH3OH Ethanoic acid CH3COOH Propanol C3H7OH Propene C3H6 Question 60
1 mark · Normal
Answer and check →The compound with the formula CH3CH2OH is correctly named:
- A.Ethanol
- B.Methanol
- C.Ethanoic acid
- D.Propanol