Line structures, also known as skeletal structures or line bond structures, are a simplified way of drawing organic molecules that are commonly used by organic and biological chemists. The convention is quite simple and makes it easier to draw molecules, but line structures do take a little bit of getting used to. Carbon atoms are depicted not by a capital C, but by a corner between two bonds, or a free end of a bond. Open-chain molecules are usually drawn out in a zig-zig shape. Hydrogens attached to carbons are generally not shown: rather, like lone pairs, they are simply implied (unless a positive formal charge is shown, all carbons are assumed to have a full octet of valence electrons). Hydrogens bonded to nitrogen, oxygen, sulfur, or anything other than carbon are shown, but are usually drawn without showing the bond.
Line structures are used to represent organic molecules in a compact and simplified way. They are particularly useful for larger, more complex biological molecules, where it becomes impractical to use full Lewis structures. Line structures make it much easier to see the basic structure of the molecule and the locations where there is something other than C-C and C-H single bonds.
In order to interpret condensed and line structures, it is important to understand how to draw them. To draw the condensed structure of a given Lewis Structure or line structure, one must first understand the basic structure of the molecule. For example, if you look ahead in a chapter on organic chemistry, you will see that the figures are somewhat different from the Lewis structures you are used to seeing in your general chemistry book. In some sources, you will see condensed structures for smaller molecules instead of full Lewis structures. To draw the line structure of a given Lewis Structure or condensed structure, one must understand the convention of line structures. Carbon atoms are depicted not by a capital C, but by a corner between two bonds, or a free end of a bond. Open-chain molecules are usually drawn out in a zig-zig shape. Hydrogens attached to carbons are generally not shown: rather, like lone pairs, they are simply implied (unless a positive formal charge is shown, all carbons are assumed to have a full octet of
Line Diagram Chemistry image
