IUPAC name will be

$\begin{array}{*{20}{c}}
{C{H_3} - CH - CH - C{H_3}\xleftarrow[{ether}]{{Na}}R\,' - Br\,\xrightarrow{{Mg}}'D'\,\xrightarrow{{{H_2}O}}E} \\
{\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\
{\,\,\,\,\,C{H_3}\,\,\,\,\,C{H_3}\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,}
\end{array}$

→

The reaction $Pb \left( NO _3\right)_2$ and $NaCl$ in water produces a precipitate that dissolves upon the addition of $HCl$ of appropriate concentration. The dissolution of the precipitate is due to the formation of

→

According to Molecular Orbital Theory,

($A$) $\mathrm{C}_2^{2-}$ is expected to be diamagnetic

($B$) $\mathrm{O}_2{ }^{2+}$ is expected to have a longer bond length than $\mathrm{O}_2$

($C$) $\mathrm{N}_2^{+}$and $\mathrm{N}_2^{-}$have the same bond order

($D$) $\mathrm{He}_2^{+}$has the same energy as two isolated He atoms

→

The correct order of the ionic radii of

$O ^{2-}, N ^{3-}, F ^{-}, Mg ^{2+}, Na ^{+}$ and $Al ^{3+}$ is

→