Audi smoking exhaust What petrol is? Definition by Wikipedia
Gasoline also known as petrol outside North America, is a transparent, petroleum-derived liquid that is used primarily as a fuel in internal combustion engines. It consists mostly of organic compounds obtained by the fractional distillation of petroleum, enhanced with a variety of additives.
On average, a 42-gallon barrel of crude oil (159 L) yields about 19 US gallons (72 L) of gasoline when processed in an oil refinery, though this can and does vary based on the crude oil source's assay.
The characteristic of a particular gasoline blend to resist igniting too early (which causes knocking and reduces efficiency in reciprocating engines) is measured by its octane rating. Gasoline is produced in several grades of octane rating. Tetraethyllead and other lead compounds are no longer used in most areas to regulate and increase octane-rating, but many other additives are put into gasoline to improve its chemical stability, control corrosiveness and provide fuel system 'cleaning,' and determine performance characteristics under intended use. Sometimes, gasoline also contains ethanol as an alternative fuel, for economic or environmental reasons.
Źródło: https://en.wikipedia.org/wiki/Gasoline
When the mechanic?
Nowadays, the fast pace of life makes that we can not always afford to rest and leisure. So when the car comes to a minor fault, which in no way affects the ride comfort, usually we ignore it. Of course, much it depends on where there was such a small failure and whether it affects the operation of other mechanisms or systems in the car. But keep in mind that even a small problem can lead to much bigger problems. It happens that neglected for a long time fault can lead to more serious damage. As a result, rather than pay less for parts and replace them, we have to bear higher costs related to the comprehensive service.
Oil - not only for cooking
An oil is any neutral, nonpolar chemical substance that is a viscous liquid at ambient temperatures and is both hydrophobic (immiscible with water, literally "water fearing") and lipophilic (miscible with other oils, literally "fat loving"). Oils have a high carbon and hydrogen content and are usually flammable and slippery.
The general definition of oil includes classes of chemical compounds that may be otherwise unrelated in structure, properties, and uses. Oils may be animal, vegetable, or petrochemical in origin, and may be volatile or non-volatile. They are used for food, fuel, lubrication, and the manufacture of paints, plastics, and other materials. Specially prepared oils are used in some religious ceremonies as purifying agents.
Źródło: https://en.wikipedia.org/wiki/Oil