Understanding Alkane Halogenation

What is the general formula for alkanes?

Which of the following is a product of the chlorination of methane?

• Ethane

• Chloroethane

• Chloromethane

• Dichloroethane

Explain why the halogenation of alkanes is considered a substitution reaction.

• Because a hydrogen atom is replaced by a halogen atom.

• Because a halogen atom is added to the alkane.

• Because a double bond is formed.

• Because a halogen atom is removed from the alkane.

Describe the role of ultraviolet light in the halogenation of alkanes.

• It acts as a catalyst to speed up the reaction.

• It provides the energy needed to break the halogen molecule into radicals.

• It cools down the reaction mixture.

• It is used to dissolve the reactants.

Predict the major product of the bromination of propane and justify your answer.

• 1-bromopropane, because the reaction favors the formation of primary radicals.

• 2-bromopropane, because the reaction favors the formation of more stable secondary radicals.

• 1,2-dibromopropane, because the reaction always leads to di-substitution.

• 1,3-dibromopropane, because the reaction favors the formation of tertiary radicals.

What is the mechanism involved in the halogenation of alkanes?

• Electrophilic addition

• Nucleophilic substitution

• Free radical substitution

• Elimination

Analyze the effect of temperature on the selectivity of halogenation reactions.

• Higher temperatures increase selectivity for primary radicals.

• Higher temperatures decrease selectivity, leading to a mixture of products.

• Higher temperatures have no effect on selectivity.

• Higher temperatures increase selectivity for tertiary radicals.

Which halogen is least reactive in the halogenation of alkanes?

• Fluorine

• Chlorine

• Bromine

• Iodine

Design an experiment to demonstrate the halogenation of an alkane, including the necessary safety precautions.

• Use a closed system with a halogen lamp and ensure proper ventilation.

• Use an open flame to initiate the reaction and wear protective goggles.

• Mix the alkane and halogen in a beaker and leave it in sunlight.

• Use a microwave to heat the mixture and wear gloves.