Unit 3: Structure 3: Classification of Matter
Topic 3.2: Functional Groups — Classification of Organic Compounds Questions
Practice 20 exam-style questions for IB Chemistry Topic 3.2. Review the question stems below, then unlock the full Question Bank to access markschemes, model answers, and AI grading.
1Draw1 mark
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Draw the two structural isomers of this compound.
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State what a skeletal formula shows and what it leaves out.
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State the general formula of the homologous series of alkanes, and explain why successive members differ by CH₂. [2]
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Glucose has the molecular formula C₆H₁₂O₆.
Deduce its empirical formula.
Deduce its empirical formula.
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Identify one piece of experimental evidence showing that benzene does not contain alternating single and double carbon-carbon bonds.
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State the number of chiral centres in 3-bromobutan-2-ol, CH3-CHBr-CH(OH)-CH3.
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Draw or describe the full structural formula and the condensed structural formula of propan-2-ol.
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State what is meant by an empirical formula, a molecular formula and a structural formula, using ethanoic acid as an example.
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Explain why CH₃CH₂CH₂CH₃ and CH₃CH(CH₃)CH₃ have the same molecular formula but different boiling points.
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Deduce the molecular formula of a compound whose empirical formula is CH₂ and whose relative molecular mass is 56.
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Define a homologous series and state three features shared by its members.
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State the general formula of the alkanes, alkenes and alcohols, and name the first member of each series.
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Explain why the boiling points of the alkanes increase steadily as the number of carbon atoms increases.
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Explain why the boiling points of straight-chain alkanes increase with chain length.
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Outline how the molecular ion peak is identified in a mass spectrum.
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Explain why the ¹H NMR spectrum of ethanol shows three signals.
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Calculate the number of structural isomers it has.
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Outline the condition for a molecule to show optical isomerism.
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Give the IUPAC name of CH₃CH₂CH₂COOH and of CH₃CH(CH₃)CH₂OH.
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Compounds A and B both have the molecular formula C₃H₈O. A is propan-1-ol and B is methoxyethane. State what term describes their relationship, and state one physical property in which they differ, with a reason.
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