Question

find out the different types of petrol and diesel that are available at petrol bunk

Answer 1

Branded petrol in India, was actually started by Bharat petroleum. The name is Speed.
This difference between normal petrol and branded petrol is that these have some additives which increases the octane number and hence is better for the engine.
Besides that, for normal petrol the prices are fixed as per norms by government. Speed, being a branded petrol, the prices are not fixed as per norms by govt but is decided by the petroleum companies.
Also, it was spread that using branded petrol after using normal petrol may degrade the engine life which is not at all true. Also, the brand petrol decreases emissions and it increases the mileage as well. The prices are little higher though
Diesel, also called petrodiesel in Technical Terms, is called High Speed Diesel (HSD) which is also produced from the fractional distillation of crude oil between 200 °C and 400 °C resulting in a mixture of carbon chains and is composed of saturated hydrocarbons (primarily paraffins including n, iso, and cycloparaffins), and aromatic hydrocarbons (including naphthalenes and alkylbenzenes).
The principal measure of Diesel fuel quality is its cetane number . A higher cetane number indicates that the fuel ignites more readily when sprayed into hot compressed air.
Diesel engines do not use high-voltage spark ignition (spark plugs) burning the fuel in more air than is required for the chemical reaction. They thus use less fuel. Because they have high compression ratios and no throttle, diesel engines are more efficient than many spark-ignited engines. Engines running on diesel also provide more torque, and are less likely to stall , as they are controlled by a mechanical or electronic governor.