Why octane is used as fuel ?

Answer 1

Its used in fuel because it resists autoignition, which is the ignition temperature of a substance is the lowest temperature at which a chemical will spontaneously ignite in a normal atmosphere, without an external source of ignition, such as a flame or spark. Autoignition causes engine-knocking.

Answer 2

Octane is an alkane with the chemical formula C8H18. It has 18 isomers.

One of the isomers, 2,2,4-trimethylpentane or isooctane, is of major importance, as it has been selected as the 100 point on the octane rating scale, with n-heptane as the zero point. Octane ratings are ratings used to represent the anti-knock performance of petroleum-based fuels (octane is less likely to prematurely combust under pressure than heptane), given as the percentage of 2,2,4-trimethylpentane in an 2,2,4-trimethylpentane / n-heptane mixture that would have the same performance. It is an important constituent of gasoline.
This means that octane itself is not used as fuel.

Answer 3

Octane rating is a measure of anti-knock properties of a fuel. The compound isooctane is given a rating of 100. It burns well (does not knock) in an engine.

Answer 4

Octane is not exactly the fuel, its "simplified" to iso-octane for motor vehicles.

This fuel in gasoline engines provides the resistance to self-combustion thus requires a spark to initiate the combustion/energy release/explosion.

However, Diesel is centane based as the compression itself causes it to self combust, no spark is required.

Answer 5

Previous answers are correct, but fail to mention that octane was added when fuel became unleaded, to act as a lead substitute.

Answer 6

Its not fuel but standardization liquid for good quality Petrol as pure iso-octane has no knock inside PETROL ENGINES