Multiple choice Which of the following is used as a test fuel component in antiknock test engines? n-Heptane Hexabromocyclododecane Hexafluoroisopropanol Hexafluoroacetone Reveal answer Fill a bubble to check yourself A Correct answer Explanation n-Heptane is the straight-chain alkane with the chemical formula H3C(CH2)5CH3 or C7H16. When used as a test fuel component in antiknock test engines, a 100% heptane fuel is the zero point of the octane rating scale.