The petrol of octane number 80 has :

Options

A. 80% n-heptane + 20% iso-octane
B. 20% n-heptane + 80% iso-octane
C. 20% n-heptane + 80% n-octane
D. 80% n-heptane + 20% n-octane

Answer

B

Explanation

(B) Octane number is the percentage of iso-octane (2, 2, 4-trimethylpentane) in a mixture of iso- octane and n-heptane which has the same anti- knock properties as the given fuel. Thus a mixture having 80% iso-octane and 20% n-heptane has a octane number of 80.