$A$ fuel contains $25 \%$ $n-$heptane and $75 \%$ iso-octane. Its octane number is

The smallest compound,which on photochlorination produces diastereomers is

Give the decreasing order of reactivity for the halogenation reaction of alkanes.

$A$ sample of $2,3-$dibromo$-3-$methylpentane is heated with zinc dust. The resulting product is isolated and then heated with $HI$ in the presence of red phosphorus. Indicate the structure that represents the final organic product formed in the reaction.

The reaction,$CH_3Br + Na \to$ Product,is called

$n$-Butane $\xrightarrow{Cl_2/hv}$ Give the total number of monochloro products (including stereoisomers) possible in the above reaction.