Topic 18: Organic Chemistry – Arenes

Be able to use thermochemical, X-ray diffraction and infrared data as evidence for the structure and stability of the benzene ring Students may represent the structure of benzene as or as appropriate in equations and mechanisms.

Use —thermochemical, x-ray diffraction and infrared data as evidence for the structure and stability of the benzene ring students to connect the rule to the data and decision in the question.

This matters because —thermochemical, x-ray diffraction and infrared data as evidence for the structure and stability of the benzene ring students determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —thermochemical, x-ray diffraction and infrared data as evidence for the structure and stability of the benzene ring students to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —Thermochemical, X-ray diffraction and infrared data as evidence for the structure and stability of the benzene ring Students is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Understand that the delocalised model for the structure of benzene involves overlap of p-orbitals to form π-bonds.

Use —the delocalised model for the structure of benzene involves overlap of p-orbitals to form π-bonds to connect the rule to the data and decision in the question.

This matters because —the delocalised model for the structure of benzene involves overlap of p-orbitals to form π-bonds determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —the delocalised model for the structure of benzene involves overlap of p-orbitals to form π-bonds to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —The delocalised model for the structure of benzene involves overlap of p-orbitals to form π-bonds is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Understand why benzene is resistant to bromination, compared to alkenes, in terms of delocalisation of π-bonds in benzene compared to the localised electron density of the π-bond in alkenes.

Use —why benzene is resistant to bromination, compared to alkenes, in terms of delocalisation of π-bonds in benzene compared to connect the rule to the data and decision in the question.

This matters because —why benzene is resistant to bromination, compared to alkenes, in terms of delocalisation of π-bonds in benzene compared determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —why benzene is resistant to bromination, compared to alkenes, in terms of delocalisation of π-bonds in benzene compared to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —Why benzene is resistant to bromination, compared to alkenes, in terms of delocalisation of π-bonds in benzene compared is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Know the following reactions of benzene, limited to: i oxygen in air (combustion to form a smoky flame) ii bromine, in the presence of a catalyst iii a mixture of concentrated nitric and sulfuric acids iv fuming sulfuric acid v halogenoalkanes and acyl chlorides with aluminium chloride as catalyst (Friedel-Crafts reaction).

Use —the following reactions of benzene to connect the rule to the data and decision in the question.

This matters because —the following reactions of benzene determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —the following reactions of benzene to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —The following reactions of benzene is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Understand the mechanism of the electrophilic substitution reactions of benzene in halogenation, nitration and Friedel-Crafts reactions, including the generation of the electrophile.

Use —the mechanism of the electrophilic substitution reactions of benzene in halogenation, nitration and friedel-crafts reactions to connect the rule to the data and decision in the question.

This matters because —the mechanism of the electrophilic substitution reactions of benzene in halogenation, nitration and friedel-crafts reactions determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —the mechanism of the electrophilic substitution reactions of benzene in halogenation, nitration and friedel-crafts reactions to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —The mechanism of the electrophilic substitution reactions of benzene in halogenation, nitration and Friedel-Crafts reactions is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.

Understand the reaction of phenol with bromine water and the reasons for the relative ease of this reaction compared to benzene.

Use —the reaction of phenol with bromine water and the reasons for the relative ease of this reaction compared to benzene to connect the rule to the data and decision in the question.

This matters because —the reaction of phenol with bromine water and the reasons for the relative ease of this reaction compared to benzene determines what can be inferred or chosen; begin with the stated conditions and keep the conclusion tied to the evidence.

Example: apply —the reaction of phenol with bromine water and the reasons for the relative ease of this reaction compared to benzene to one small, clearly defined case, show the key step or comparison, and explain the result in words.

Boundary: —The reaction of phenol with bromine water and the reasons for the relative ease of this reaction compared to benzene is not a universal recommendation. Check the syllabus scope, assumptions, units and the limits of the evidence before generalising.