Structural formula
Many chemical compounds, especially hydrocarbons, can exist in different geometric configurations. A structural formula represents the arrangements of atoms in a way that a chemical formula cannot.A simple example of this may be seen with the hydrocarbon butane, C4H10. The four carbons may be arranged in a linear pattern, or in a branched, "T" pattern. The first arrangement is known as orthobutane, while the second is isobutane. One of the problems with structural formulae is the inability to tell the structure of the compound (see isomer).
A structural formula is named using IUPAC nomenclature.
Ring structure
A ring structure can be drawn in chair perspective.