Question

What is the chemical formula for petrol and diesel?

Answer 1

Hint: We know that petrol and diesel are used as fuel in various vehicles such as cars, trucks, motorbikes, etc. They are used in various machineries. We get petrol and diesel from a source called petroleum.

Complete answer:
We all have seen petrol and diesel, they are present in liquid form. They are mainly used as fuel in automobiles and various machines. Now let’s study about petrol and diesel first before studying about its chemical formula.
Petrol
Petrol is a liquid mixture which is derived from a source called petroleum. In this liquid mixture, mostly aliphatic hydrocarbons are present and it is improved with the presence of aromatic hydrocarbons such as toluene, iso-octane or benzene. Aromatic hydrocarbons increase their octane ratings which can be defined as a measure of a fuel to avoid knock which is caused when there is premature ignition in the cylinder of an engine which further destroys the engine.
Now let’s talk about its chemical composition. As we have learned above, petrol consists of hydrocarbons. Now the hydrocarbons have carbon atoms from \[5\] to \[12\] per molecule. But it is not fixed as petrol is blended as per the need. A typical petrol is a mixture of various chemicals such as paraffin, olefins and naphthalene. Petrol has a basic chemical formula since it is a mixture of various chemicals and is also blended as per its need. So, it’s general chemical formula is ${C_n}{H_{2n + 2}}$.
Diesel
Diesel is also derived from a source called petroleum. It is also used as a fuel for diesel based engines. Diesel engines were invented by an engineer named Rudolf Diesel. As we have seen, it is also used in liquid form. When fractional distillation is done on petroleum fuel oil then we obtain diesel from it, and this type of diesel is most common.
Now let’s talk about its chemical composition. Diesel is also a mixture of various hydrocarbons (aliphatic or aromatic). Diesel is a mixture of $25\% $ of aromatic hydrocarbons such as alkyl benzenes and naphthalene and $75\% $ of saturated hydrocarbons such as paraffin. Its chemical formula is ranging from ${C_{10}}{H_{20}} - {C_{15}}{H_{28}}$.

Note:
As we have seen above petrol and diesel do not have any specific formula but it has a range of formula since its hydrocarbon chains keeps on changing as per our needs. We blend these fuels according to the need of the machine.