Nucleophilic and Electrophilic Substitution

The video introduces two key reactions in IB Chemistry topic 10.2: nucleophilic and electrophilic substitution. Nucleophilic substitution involves a halogenoalkane reacting with sodium hydroxide, where the chlorine atom is replaced by a hydroxide ion. Electrophilic substitution involves benzene reacting with bromine in the presence of a catalyst, where a hydrogen atom is replaced by a bromine atom. Both reactions are explained with examples, highlighting the roles of nucleophiles and electrophiles.

What are the two types of reactions introduced in this section?

• Oxidation and reduction

• Hydrolysis and condensation

• Nucleophilic substitution and electrophilic substitution

• Nucleophilic addition and electrophilic addition

In the nucleophilic substitution example, what is the role of the hydroxide ion?

• It acts as a catalyst

• It acts as a solvent

• It acts as a nucleophile

• It acts as a Lewis acid

What happens to the chlorine atom in the nucleophilic substitution reaction?

• It is replaced by a hydroxide ion

• It is reduced

• It is oxidized

• It forms a double bond

What is the significance of the lone pair on the hydroxide ion in nucleophilic substitution?

• It donates electrons to form a new bond

• It accepts electrons from the carbon atom

• It stabilizes the reaction intermediate

• It acts as a catalyst

What catalyst is used in the electrophilic substitution reaction with benzene?

• H2SO4

• AlCl3

• FeBr3

• FeCl3

In electrophilic substitution, what happens to the bromine molecule before it reacts with benzene?

• It is dissolved

• It is reduced

• It is oxidized

• It is polarized

What role does FeBr3 play in the electrophilic substitution reaction?

• It acts as a solvent

• It acts as a nucleophile

• It acts as a Lewis base

• It acts as a Lewis acid

What is the result of the electrophilic substitution reaction between benzene and bromine?

• Formation of benzene chloride

• Formation of benzene fluoride

• Formation of benzene oxide

• Formation of benzene bromide

What is the main difference between nucleophilic and electrophilic substitution reactions?

• Both involve electron donation

• Nucleophilic substitution involves electron acceptance, while electrophilic substitution involves electron donation

• Nucleophilic substitution involves electron donation, while electrophilic substitution involves electron acceptance

• Both involve electron acceptance

Which of the following is true about a Lewis acid in the context of electrophilic substitution?

• It donates a lone pair of electrons

• It accepts a lone pair of electrons

• It forms a covalent bond with a nucleophile

• It acts as a reducing agent