The volume of $HCl$, containing $73\,g\,L ^{-1}$, required to completely neutralise $NaOH$ obtained by reacting $0.69\,g$ of metallic sodium with water, is $........mL$. (Nearest Integer) (Given : molar Masses of $Na , Cl , O , H$ are $23$, $35.5,16$ and $1\,g\,mol ^{-1}$ respectively)
→$IUPAC$ name of the following compound is $\begin{array}{*{20}{c}}
{\,H\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\
{|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\
{C{H_3} - C - C{H_2} - C{H_3}} \\
{|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\
{{C_6}{H_5}\,\,\,\,\,\,\,\,\,}
\end{array}\,$
→The electrons, identified by quantum by numbers $n$ and $l,$ $(i)\, n = 4, l = 1$ $(ii)\, n = 4, l= 0$ $(iii)\, n = 3, l= 2$ $(iv)\,n = 3, l = 1$ can be placed in order of increasing energy, from the lowest to highest, as
→