The conversion of ethyl bromide to ethyl iodide using sodium iodide and dry acetone is known as:

The reactivities of $methyl$ $chloride$,$propyl$ $chloride$ and $chlorobenzene$ are in the order:

Which of the following is product $A$ in the above reaction?

$A$ dihalogen derivative $X$ of a three-carbon hydrocarbon reacts with alcoholic $KOH$ to give another hydrocarbon,which gives a red precipitate with ammoniacal $Cu_2Cl_2$. Reaction of $X$ with aqueous $KOH$ gives an aldehyde. The compound $X$ is .......

Which of the following pairs of compounds on heating gives butanenitrile?

Which of the following species is most reactive in $S_{N}2$ reaction?