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11.1 Organic Compounds

11.2 The Tetrahedral Structure of Carbon

11.3 Polarity of Organic Molecules

Chapter 11 Introduction to Organic Chemistry

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Carbon Carbon has 4 valence electrons; hydrogen has 1.

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• C • H • •

To achieve an octet, carbon forms four bonds. H H

• • |H C H H—C—H CH4 , methane

• • | H H

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Organic Molecules

In organic molecules, valence electrons form covalent bonds between carbon atoms.

H H H H• • • • | |

H C C H H—C—C—H • • • • | | H H H H

Ethane, CH3—CH3

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Other Covalent Bonds Carbon atoms form bonds mostly with H

and other C atoms, but also with atoms of O, N, S, and halogens F, Cl, and Br.

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Tetrahedral Structure of Carbon

When a carbon atom has four single covalent bonds, VSEPR theory predicts that the bonds and their atoms are arranged in a tetrahedral shape.

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Tetrahedral Structure of Carbon

In molecules with two or more carbon atoms, each carbon atom with four single bonds has a tetrahedral shape.

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Polarity of Organic Molecules

The covalent bonds C-C and C-H are nonpolar. Covalent bonds in which C bonds with O, N, F,

Cl, or Br are polar. Organic molecules are nonpolar when dipoles

cancel and polar when dipoles do not cancel.

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Organic Compounds

Typically, organic compounds Contain carbon. Have covalent bonds. Have low melting points. Have low boiling points. Are flammable. Are soluble in nonpolar solvents.