Hydrocarbons

compounds of carbon with hydrogen. They form the basis of organic chemistry.

Depending on the arrangement of the C-atoms, one divides:

• acyclic or aliphatic hydrocarbons. The carbon atoms are connected with each other in a chain. The saturated hydrocarbons are also called paraffins (alkanes). Unsaturated hydrocarbons with double bonds are called alkenes with triple bonds are called alkynes.
• Cyclic hydrocarbons. The carbon atoms are connected to each other in a ring. Aromatic hydrocarbons (trivial nomenclature also known as aromatics) are cyclic compounds with conjugated double bonds. Polycyclic aromatic hydrocarbons (PAH) are often carcinogenic hydrocarbons with fused ring systems.