Which of the following has the higest knocking property ?

Options

A. Aromatic hydrocarbons
B. Olefins
C. Branched chain paraffins
D. Straight chain paraffins

Answer

4

Explanation

Knocking character of fuels is increased with decrease in octane number. The octane number increase in the order straight chain alkane `lt` branched chain alkanes `lt` olefins `lt` cycloalkenes `lt` aromatic compounds. Since straight chain alkanes have minimum octane number, hence they produce maximum knocking.