Chapter 21- An Introduction to Organic Chemistry

• All organic compounds contain carbon. However, not all compounds containing carbon are organic.

• Organic compounds may have hydrogen, oxygen, nitrogen and sulfur etc in addition to carbon.

• Compounds that contain carbon and hydrogen only are called hydrocarbons.

HOMOLOGOUS SERIES AND FUNCTIONAL GROUPS

• A homologous series is a family of organic compounds with similar chemical properties.

• Compounds of the same homologous series contain the same functional group.

• A functional group is an atom or a group of atoms that give the molecule its characteristic properties.

• The general characteristics of the homologous series are: same functional group, similar chemical properties, and gradual change in physical properties.

NAMING ORGANIC COMPOUNDS

• Names of organic compounds are divided into two parts: a prefix that tells the total number of carbon atoms in the compound, and the suffix that names the homologous series of the compound.

• Prefixes: meth- (one), eth- (two), prop- (three), but- (four)

• Suffixes: -ane (alkane), -ene (alkene), -ol (alcohol), -oic acid (carboxylic acid)

FRACTIONAL DISTILLATION

• Petroleum is a mixture of hydrocarbons that are separated by fractional distillation due to the difference in boiling points.

• The crude oil is heated. At different boiling points, different factions boil over.

• Factions from first to last: refinery gas, gasoline, naptha, kerosine, lubricating oil, bitumen.

USES OF FACTIONS

• Petroleum gas: heating and cooking.

• Gasoline: fuel for car engines.

• Naptha: feedstock for chemical industry.

• Kerosine (paraffin): fuel for aircraft engines.

• Diesel oil: fuel for diesel engines.

• Lubricating oil: lubricating machines.

• Bitumen: paving road surfaces.