The C<sub>4</sub>-benzenes are a class of organic aromatic compounds which contain a benzene ring and four other carbon atoms. There are three tetramethylbenzenes, six dimethylethylbenzenes, three diethylbenzenes, three isopropylmethylbenzenes, three n-propylmethylbenzenes and four butylbenzenes. The saturated compounds have formula C<sub>10</sub>H<sub>14</sub> and molecular weight 134.22 g/mol. C<sub>4</sub>-benzenes are found in petroleum. Petrol (gasoline) can contain 5-8% C<sub>4</sub>-benzenes.