Organic Chemistry

Introduction Organic chemistry is the study of carbon and its compounds. The major sources of carbon are the fossil fuels petroleum, natural gas, and coal. Currently, about 7 million organic compounds account for about 90% of all known substances. Each year, over 50,000 new organic compounds are synthesized.

Introduction, Continued A hydrocarbon is a compound that contains only carbon and hydrogen. A hydrocarbon derivative is a compound derived from a hydrocarbon, but containing other elements, such as fluorine, nitrogen, and oxygen. There are two types of hydrocarbons: 1.Saturated hydrocarbons 2.Unsaturated hydrocarbons

Hydrocarbons –Compound made up entirely of carbon and hydrogen –Majority of petroleum components –Carbon always forms four bonds. –Hydrogen always forms one bond.

Petroleum –Primary use as a fuel –Used for many other products as well Examples are fertilizers, insecticides, plastics, food preservatives, paints, inks, lubricants, detergents, solvents, and medicines.

Chains of carbon –Chain length—number of carbon atoms in the longest continuous chain Chain length of eight

Linear hydrocarbon –Each of the nonterminal carbons are attached to two other carbon atoms –Does not form a straight line of carbons since the bonding angle is 109.5°

Branched hydrocarbon –At least one carbon atom is attached to more than two other carbon atoms. –Small branch forming off the main carbon chain

For the following molecule what is the length of the main chain and what is the length of the branch chain?

For the following molecule what is the length of the main chain and what is the length of the branch chain? Main chain: six carbons Branch chain: two carbons

Line drawings –Representation showing only the C—C bonds, omitting the H bonds –Bonds not shown are assumed to be H bonds.

Double and triple bonds are shown with multiple dashes.

What would the molecular formula be for each of the following molecules:

What would the molecular formula be for each of the following molecules: (a) C 7 H 16 (b) C 6 H 12 (c) C 6 H 6

Saturated Hydrocarbons A saturated hydrocarbon has only single bonds between the carbon atoms. Carbon can form four single covalent bonds to other atoms. A saturated hydrocarbon with only single bonds belongs to the alkane family.

Unsaturated Hydrocarbons An unsaturated hydrocarbon has either a double or triple bond between two carbon atoms. –If it has a double bond, it is an alkene (b). –If it has a triple bond, it is an alkyne (c). An aromatic hydrocarbon has a benzene ring. A benzene ring is a six-membered ring of carbon atoms with alternating single and double bonds (d).

Classification of Hydrocarbons Below is a flowchart for the classification of hydrocarbons.

Structural Isomers Two compounds with the same molecular formula, but different structural formulas are isomers. Butane has the formula C 4 H 10. We can draw the formula in two ways: CH 3 CH 2 CH 2 CH 3 and CH 3 CH(CH 3 )CH 3 The two isomers have different physical properties.

Structural Isomers Isomers –Compounds with the same formula, but different structures