Alkanes and Aromatic Hydrocarbons Organic Compounds Bonding in Hydrocarbons Naming Alkanes Properties of Alkanes

“ The most important hypothesis in all of biology…is that everything that animals do, atoms do. In other words, there is nothing that living things do that cannot be understood from the point of view that they are made of atoms acting according to the laws of physics.” Richard Feynman ( )

Organic Compounds  Contain carbon  Have covalent bonds  Have low melting points  Have low boiling points  Burn in air (oxygen)  Are soluble in nonpolar solvents  Form large molecules

Alkanes Contain C and H only Contain single bonds C-C Have 4 bonds to every carbon (C) atom Are nonpolar

Complete Structural Formulas Show the bonds between each of the atoms H H  H  C  HH C H  H H CH 4, methane

More Alkanes H HCondensed Structural Formulas H C C HCH 3 CH 3 H HEthane H H H H C C C HCH 3 CH 2 CH 3 H H H Propane

IUPAC Names Name# carbons Structural Formula Methane1CH 4 Ethane2CH 3 CH 3 Propane3CH 3 CH 2 CH 3 Butane4CH 3 CH 2 CH 2 CH 3 Pentane5CH 3 CH 2 CH 2 CH 2 CH 3

IUPAC NAMES Name # carbons Structural Formula Hexane 6 CH 3 CH 2 CH 2 CH 2 CH 2 CH 3 Heptane 7 CH 3 CH 2 CH 2 CH 2 CH 2 CH 2 CH 3 Octane 8 CH 3 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 3 Nonane 9 CH 3 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 3 Decane 10 CH 3 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 3

Learning Check A. What is the condensed formula for H H H H H C C C C H H H H H B. What is its molecular formula? C. What is its name?

Solution A.CH 3 CH 2 CH 2 CH 3 B. C 4 H 10 C.butane

Reactions of Alkanes Combustion alkane + O 2 CO 2 + H 2 O + heat

Combustion In the Cell Metabolic oxidation is combustion C 6 H 12 O 6 + 6O 2 6CO 2 + 6H 2 O + heat glucose

Learning Check Complete the combustion reaction for C 3 H 8 + O 2 + Balance your equation

Solution Step 1 C 3 H 8 + O 2 CO 2 + H 2 O Step 2 C 3 H 8 + O 2 3 CO H 2 O Step 3 C 3 H O 2 3 CO H 2 O

Learning Check Complete and balance the reaction for the complete combustion of C 7 H 16

Solution Step 1 C 7 H 16 + O 2 CO 2 + H 2 O Step 2 C 7 H 16 + O 2 7 CO H 2 O Step 3 C 7 H O 2 7 CO H 2 O