Question

$n$-hexadecane (cetane) has cetane number

• A. 110
• B. 90
• C. 100
• D. zero

Answer 1

Answer: (C)

The quality of diesel fuel is expressed in terms of cetane number. Cetane number of a sample of diesel is the percentage of cetane by volume in a mixture of cetane and $\alpha$-methylnaphthalene which has the same ignition properties as the diesel under examination in a test engine.
Cetane ( $n$-hexadecane) ignites rapidly and is given a cetane number of $100$ , whereas $\alpha$-methyl-naphthalene ignites slowly and is given a cetane number of zero.