knowledge of the entire periodic table is not necessary to easily recall those things seen commonly with organic molecules. The harder part of organic chemistry is determining how to write out these molecules.
BONDING TRENDS IN ORGANIC CHEMISTRY Using the typical methods used for identifying organic molecules does not work very well, especially when the molecules are large and when there are basically strings of carbon atoms in varying arrangements. For this reason, there are things you need to know in order to write the different organic molecules. All organic molecules are carbon-based and, as you know, it has the ability to form four separate bonds. There are different ways to write this using the chemical abbreviation for carbon. Figure 9 shows what it looks like to write carbon in smaller molecules:
Figure 9.
Hydrogen is also relatively easy. It has one electron and can only have one bond and will have no formal charge. The exception is the single proton H+, and the hydride ion, H-. The hydride ion is a proton plus two electrons. These are highly reactive molecules that do not exist in nature but are important in discussing the chemistry of organic molecules. Next comes oxygen. This exists in one of three ways. It can exist in a neutral way with two bonds and two lone pairs of electrons. It can also become single-bonded with a negative-one negative charge. Lastly, it can come triple-bonded with a formal positive-
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