Fundamentals of Carbon Chemistry

Natural sources of carbon compounds

- Fractional Distillation and cracking of crude oil

- Fractional Distillation: Crude oil is a mixture of hydrocarbon compounds with different b.p.

- Cracking: breaking down of large molecules of hydrocarbons into smaller ones

  (1) methods: Thermal cracking and catalytic cracking

  (2) important uses: change heavy oil to petrol to meet market demand; source of alkenes

Unique nature of carbon

Catenation: the ability of one element to form chains or rings in which its atoms are bounded one another

Characteristics of homologous series

- same functional group

- similar chemical properties

- show a gradual change in physical properties

Isomerism (95 essay question)

- existence of different compounds with the same molecular formula but different structural formula

- Isomers: compounds having the same molecular formula but with their atoms arranged differently in

  space.

- Structural isomerism: same molecular formula but different structural formula

   (1) chain isomerism: chain isomers have different carbon skeletons; do not have same physical

         properties.

   (2) Functional isomerism: isomers with different functional group

   (3) Position isomerism: same carbon skeletons and functional group but they differ in positions occupied

        by functional group.

- Geometrical isomerism (cis-trans isomerism):

  (1) free rotation about C=C bond is prevented because this will break the pi-bond.

  (2) same molecular formula and structural formula

  (3) difference in the arrangement of atoms in space

  (4) do not have same physical properties, so can be separated by physical methods

        trans-isomer: more regular shape --> packing of molecules more closelyy --> higher m.p.

        cis-isomer: less regular shape --> packing of molecules less closelyy --> lower m.p.

  (5) contain same functional group(s), hence similar chemical properties

Naming derivatives of hydrocarbons

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