Carbon Skeletons

Organic compounds have a backbone of carbon atoms called the carbon skeleton. A carbon atom is tetravalent, so it can form up to four covalent bonds.

It often bonds with atoms such as hydrogen, nitrogen, and oxygen. When carbon bonds with hydrogen, it forms hydrocarbons. Hydrocarbons with only single bonds are called alkanes, such as methane, the simplest hydrocarbon, which has one carbon atom bonded to four hydrogen atoms.

Longer carbon chains create new molecules. These chains can be linear, as in hexane, or branched, as in isohexane.

Molecules with the same number of atoms but different arrangements are called structural isomers. Hexane and isohexane share the same chemical formula, C₆H₁₄, but hexane is linear, while isohexane is branched at the second carbon atom.

These carbon skeletons can also have double bonds at different positions, forming alkenes such as hexene, or triple bonds, forming alkynes such as hexyne. They can also form rings, as in cyclohexene.