Chemistry - Hydrocarbon Question with Solution | TestHub

Octane number is the percentage by volume of iso-octane in the mixture of$\mathrm{i}\mathrm{s}\mathrm{o}-\mathrm{o}\mathrm{c}\mathrm{t}\mathrm{a}\mathrm{n}\mathrm{e}$and$\mathrm{n}-\mathrm{h}\mathrm{e}\mathrm{p}\mathrm{t}\mathrm{a}\mathrm{n}\mathrm{e}$which has the same antiknocking properties as the fuel under examination. Given fuel (25% n-heptane +75% iso-octane) Hence, octane number = 75 (because iso octane is 75%)