The gas evolved on heating $CH_3MgBr$ in methanol is

Identify $A$ in the given chemical reaction.

Among the isomeric alkanes of molecular formula $C_{5}H_{12}$,identify the one that on photochemical chlorination yields:
$(i)$ $A$ single monochloride.
$(ii)$ Three isomeric monochlorides.
$(iii)$ Four isomeric monochlorides.

Explain the isomerization reaction of alkanes.

Identify the total number of monochlorinated products formed when $2$-methylpentane reacts with $Cl_2 / hv$.

The reaction of ethyl bromide and $n$-propyl bromide with sodium in ether gives .................