1. 1 11.1 Organic Compounds 11.2 The Tetrahedral Structure of Carbon 11.3 Polarity of Organic Molecules Chapter 11 Introduction to Organic Chemistry

2. 2 Carbon Carbon has 4 valence electrons; hydrogen has 1. C H To achieve an octet, carbon forms four bonds. H | H  C  H H—C—H CH 4, methane | H H

3. 3 Organic Molecules In organic molecules, valence electrons form covalent bonds between carbon atoms. H H | H  C  C  H H — C — C — H | | H H H H Ethane, CH 3 — CH 3

4. 4 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.

5. 5 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.

6. 6 Tetrahedral Structure of Carbon In molecules with two or more carbon atoms, each carbon atom with four single bonds has a tetrahedral shape.

7. 7 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.

8. 8 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.