Unit 6: Reactivity 3: What Are the Mechanisms of Chemical Change?
Topic 6.3: Electron Sharing Reactions Questions
Practice 17 exam-style questions for IB Chemistry Topic 6.3. Review the question stems below, then unlock the full Question Bank to access markschemes, model answers, and AI grading.
1State1 mark
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State which type of halogenoalkane reacts predominantly by an SN1 mechanism.
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Methane reacts with bromine in the presence of ultraviolet light.
Write an equation for the initiation step of this reaction and state the type of bond fission that occurs.
Write an equation for the initiation step of this reaction and state the type of bond fission that occurs.
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Unlock Question3Predict1 mark
Predict, with a reason, which mechanism operates when 2-bromo-2-methylpropane is hydrolysed by aqueous hydroxide ions.
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State what is meant by homolytic fission and explain why it produces radicals rather than ions.
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Name the three stages in the free-radical substitution of methane by chlorine, and write an equation for the stage that requires ultraviolet light.
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Write the two propagation steps for the reaction of chlorine with methane, and explain why these steps allow the reaction to continue.
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Explain why free-radical substitution of methane with chlorine produces a mixture of products rather than pure chloromethane.
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Write the equation for the initiation step of this radical substitution.
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1-chlorobutane and 1-iodobutane are each warmed separately with aqueous sodium hydroxide.
Identify which reacts faster and explain your answer in terms of the carbon–halogen bond.
Identify which reacts faster and explain your answer in terms of the carbon–halogen bond.
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Unlock Question10Distinguish3 marks
Distinguish between homolytic and heterolytic fission of a covalent bond, and state which type produces radicals.
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Which step of radical substitution produces two radicals from one?
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Which halogenoalkane reacts fastest by an SN1 mechanism?
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Draw the mechanism for this reaction, including curly arrows.
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2-bromo-2-methylpropane, (CH₃)₃CBr, is warmed with aqueous sodium hydroxide.
State the mechanism by which it reacts, write the rate equation, and explain why this mechanism operates.
State the mechanism by which it reacts, write the rate equation, and explain why this mechanism operates.
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Outline why the rate of an SN2 reaction depends on the concentration of both reactants.
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Compare the stereochemical outcome of SN1 and SN2 reactions at a chiral carbon.
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Explain the mechanism of the reaction between 1-bromopropane and aqueous sodium hydroxide, using curly arrows.
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