Aromatic hydrocarbons are those that have one or more aromatic rings in their molecule.
It is a closed chain, therefore cyclical. Alternate single and double bonds between the carbons, forming a resonance. The main aromatic is benzene C6H6.
See the ways to represent benzene.
Benzene is a colorless, volatile, flammable and very toxic liquid. It is a highly hazardous compound that should not be inhaled (breathed). May cause serious illness, including leukemia.
Most aromatics are hazardous to health. In addition to benzene, there is also benzopyrene, which forms on roast meat and smoked meats and fish, and is released in the burning of cigarettes.
Benzopyrene: carcinogenic aromatic
Toluene - extracted from a tree originating in Colombia, tolu balm. Can be used as a solvent. It has a characteristic smell.
Naphthalene - known as mothballs, sold in little balls to kill insects. From it one can produce plastics, solvents and dyes.
Anthracene - colorless solid that easily sublimates. From it can be produced dyes, insecticides and preservatives.
Phenanthrene - Found in cigarette smoke, obtained from a fraction of anthracene oil.