18. The octane number of zero is assigned to A.2-methyl octane B.n-heptane C.iso-octane D.3-methyl octane
Answer: Option B Solution: n-heptane is defined as the zero point of the octane rating scale. 2,2,4-Trimethylpentane has an octane rating of 100, whereas n-heptane has an octane rating of 0. The octane number is based on an arbitrary scale which is a measure of its ability to resist knocking, as it burns on combustion.
