Which of the following has the highest boiling point?

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

The angle strain in cyclopropane is:

$Ph^{-}MgCl \xrightarrow{\text{Hydrolysis}} \text{Product}$
Product will be

Why is Wurtz reaction not preferred for the preparation of alkanes containing an odd number of carbon atoms? Illustrate your answer by taking one example.

Identify the decreasing order of boiling point of the following alkanes:
$(i)$ $n$-pentane
$(ii)$ Isopentane
$(iii)$ Neopentane