Unit 08: Hydrocarbons and halohydrocarbons

8.0 Investigates the relationship between structure and properties of  hydrocarbons and halohydrocarbons.

8.1 Investigates the structure,physical properties and nature of bonds of aliphatic hydrocarbons.  (Only acyclic aliphatic compounds are considered).

Describes the nature of the bonds in alkanes, alkenes, and alkynes using suitable examples.

Explains the variation of physical properties along the homologous series of alkanes, alkenes and alkynes.

Relates the geometrical shapes of the simple alkanes, alkenes and alkynes to the hybridization of carbon atoms.

8.2 Investigates and compares the chemical reactions of alkanes, alkenes and alkynes in terms of their structures.

Relates the characteristic reactions of alkanes, alkenes and alkynes to their structures.

Explains the reaction mechanisms of chlorination of methane and the addition of bromine and hydrogen halides to ethene.

Identifies the alkenes and alkynes by chemical reactions.

Prepares ethene and ethyne and observes their reactions.

8.3 Investigates the nature of bonding in benzene.

Gives reasons why the structure for benzene first presented by Kekule does not explain all the properties of benzene.

Explains the structure and the stability of benzene.

Presents evidences in support of the true structure of benzene.

8.4 Analyses the stability of benzene in terms of its characteristic reactions.

Shows using suitable examples the tendency of benzene to undergo substitution reactions rather than addition reactions.

Describes the electrophilic substitution reactions as characteristic reactions of benzene using the mechanisms of nitration, alkylation, acylation and halogenation.

Compares the reactions of benzene with those of alkanes alkenes, and alkynes.

Describes the increase in the tendency to undergo oxidation of alkyl groups and acyl groups when they are attached to benzene.

8.5 Recognizes the directing abilityof substituent groups of monosubstituted benzene.

Identifies the substituent groups of mono substituted benzene as ortho, para or meta directing groups.

States the position to which a second substituent group attaches in a mono- substituted benzene on the basis of the directing property of the first substitued group.

8.6 Investigates the structure and polar nature of C-X bond and reactions of alkyl halides.

Classifies alkyl halides as primary, secondary and tertiary.

Relates the tendency of alkyl halides to undergo nucleophilic substitution reactions with the polar nature of the C – X bond.

Describes the preparation and the properties of Grignard reagent.

Explains the non reactivity of aryl halides and vinyl halides (halogens attached to sp2  carbon atoms) towards nucleophilic substitution.

8.7 Analyses the nucleophilic substitution reactions of alkylhalides in terms of the timing of  bond making and bond breaking steps.

Recognizes that there are two possible pathways for the nucleopilic substitution reactions of alkyl halides.

Describes the nucleophlic substitution reaction of alkyl halides as a one step reaction when bond breaking and bond making take place simultaneously.

Describes the nucleophilic substitution reaction of alkyl halides as a two step reaction when the formation of the new bond takes place after the breaking of the bond.