Cyclohexane bond line structure

The cyclohexane structure is structural features drawn simply as a hexagon and the cyclopentane structure as a pentagon. In such drawings, it is understood that there is a carbon in every corner and that there are two hydrogens bonded to each carbon, even though neither the hydrogens nor the bonds are shown. Such a structure is sometimes referred to as a bond-line structure (Figure 14.19a). 

As you can see in Figure 22-6, cyclic hydrocarbons such as cyclohexane are represented by condensed, skeletal, and line structures. Line structures show only the carbon-carbon bonds with carbon atoms understood to be at each vertex of the structure. Hydrogen atoms are assumed to occupy the remaining bonding positions unless substituents are present. 

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