WHAT ARE THE CONSTITUENTS OF PETROL AND DESIEL

Petrol is a complex mixture of at least 100 different compounds, mostly hydrocarbons. Petrol constituents of Aliphatic hydrocarbons which includes, Aliphatic-Straight chains Aliphatic-Branched Aliphatic-Cyclic and Aromatic Hydrocarbons mixed with iso-octane (2,2,3 trimethyl pentane) or aromatics to increase its octane rating.

Diesel is composed of about 75% saturated hydrocarbons (primarily paraffins including n, iso, and cycloparaffins), and 25% aromatic hydrocarbons (including naphthalenes and alkylbenzenes). The average chemical formula for common diesel fuel is C12H23, ranging approximately from C10H20 to C15H28.

Difference in the compositions of petrol and diesel is:

Diesel -- alkanes containing 12 or more carbon atoms

Petrol --  mixture of alkanes and cycloalkanes (5 to 12 carbon atoms)