Chapter 8: Introduction to Organic Chemistry: Hydrocarbons

The Story of Carbon

• Early scientists struggled to determine what was responsible for

the difference between living (organic matter) and non-living

organisms

1828, Friedrich Wöhler heated the inorganic salt ammonium

cyanate and produced urea (found in blood and urine.) This

discredited the “vital force” theory and since then organic

chemistry has rapidly evolved.

Organic compound:

A compound that contains the element

carbon.

Organic chemistry

The study of carbon-containing compounds.

Organic vs. Inorganic Compounds

• An estimated 500,000 inorganic compounds have been identified, but more

than 9 million organic compounds are known.

• Carbons can form stable covalent bonds with other carbon atoms and with

atoms of other elements.

Expanded structural representation:

A structural molecular formula showing all the

covalent bonds (think Lewis structures!)

Condensed structural representation:

A structural molecular formula showing the

general arrangement of atoms but without all the covalent bonds.

Skeletal structural representation:

A structural molecular formula showing carbon

atoms as points, with hydrogens bonded to carbon assumed. Other atoms (e.g., nitrogen,

oxygen, and chlorine) are shown explicitly, as well as hydrogens bonded to these

noncarbon atoms.

Functional group:

A unique reactive combination of atoms that

differentiates molecules of organic compounds of one class from those

of another.

• The arrangement of organic compounds into a relatively small number of

classes simplifies their study.

• The groups are formed because they provide distinct patterns of

reactivity. For instance, small alcohols like methanol (CH3OH) behave in

many of the same ways as much larger alcohols.

Alkane

A hydrocarbon that contains only carbon–hydrogen bonds and carbon–carbon

single bonds.

Saturated hydrocarbon:

Another name for an alkane.

Unsaturated hydrocarbon:

A hydrocarbon that contains one or more carbon–carbon

multiple bonds.