The melting points of alkanes with an odd number of carbon atoms are ............... compared to those with an even number of carbon atoms in the chain.

Alkanes are generally resistant to oxidation under mild conditions. What is your opinion regarding the following reaction?
$C_4H_{10(g)} + \frac{13}{2}O_{2(g)} \to 4CO_{2(g)} + 5H_2O_{(l)}$

Which of the following has the highest octane number?

For the reaction of $2-$methylbutane with $Cl_2$ in the presence of $hv$,let $N$ be the total number of isomeric monochlorinated products (including stereoisomers). If these products are separated by fractional distillation,let $M$ be the number of fractions obtained. Find the values of $N$ and $M$.

The major product in the following reaction is:

Which of the following does not react with $PCl_5$?