Reactivity R 3.4—Electron-pair sharing reactions SN1/SN2 HL

What is a nucleophile?

• A nucleophile is an electron pair donor in a chemical reaction.

• A nucleophile is a proton donor in a chemical reaction.

• A nucleophile is an electron pair acceptor in a chemical reaction.

• A nucleophile is a type of catalyst that speeds up reactions.

Identify a nucleophile in the reaction: CH3Br + OH- → CH3OH + Br-

• OH-

• CH3Br

• Br-

• CH3OH

Explain the role of a nucleophile in a nucleophilic substitution reaction.

• A nucleophile accepts an electron pair from an electrophile.

• A nucleophile donates an electron pair to an electrophile, facilitating the substitution of a leaving group.

• A nucleophile stabilizes the transition state without participating in the reaction.

• A nucleophile is a type of leaving group in the reaction.

What is the difference between a neutral nucleophile and a negatively charged nucleophile?

• A neutral nucleophile is more reactive than a negatively charged nucleophile.

• Negatively charged nucleophiles are always uncharged and less reactive.

• Both types of nucleophiles have the same reactivity regardless of charge.

• A neutral nucleophile is uncharged and less reactive, while a negatively charged nucleophile is more reactive due to its negative charge.

Write the equation for a nucleophilic substitution reaction involving a halogenoalkane and a hydroxide ion.

• R-X + OH- → R-OH + X-

• R-X + OH- → R-O + X-

• R-X + H2O → R-OH + HX

• R-X + OH- → R-XO + H+

Describe the movement of electron pairs in a nucleophilic substitution reaction using curly arrows.

• Electron pairs are transferred from the electrophile to the nucleophile.

• Curly arrows indicate the movement of protons to the nucleophile.

• Curly arrows represent the formation of new bonds without breaking existing ones.

• In a nucleophilic substitution reaction, curly arrows show the nucleophile donating electron pairs to the electrophile and the breaking of the bond to the leaving group.

What is heterolytic fission?

• Heterolytic fission involves the formation of neutral species from a covalent bond.

• Heterolytic fission is the equal sharing of electrons between two atoms.

• Heterolytic fission is the breaking of a bond where both electrons are lost to the environment.

• Heterolytic fission is the breaking of a covalent bond where one atom retains both electrons, leading to the formation of charged species.

Provide an example of heterolytic fission with an equation.

• HCl → H+ + Cl-

• H2O → H+ + OH-

• NaCl → Na+ + Cl-

• CH4 → C+ + 4H+

Explain how ions are formed through heterolytic fission.

• Ions are formed through heterolytic fission by the uneven breaking of a covalent bond, leading to the creation of a cation and an anion.

• Ions are formed through the equal sharing of electrons in a covalent bond.

• Ions are formed when two atoms collide and fuse together.

• Ions are created by the complete transfer of electrons from one atom to another.

What is an electrophile?

• An electrophile is a negatively charged ion that repels electrons.

• An electrophile is a chemical species that accepts electrons from a nucleophile.

• An electrophile is a type of solvent used in chemical reactions.

• An electrophile is a chemical species that donates electrons to a nucleophile.