$(i)$ $CH _{3} COOH$  $\begin{array}{*{20}{c}}
  {\begin{array}{*{20}{c}}
  {H\,\,\,\,\,\,\,O\,\,} \\ 
  {|\,\,\,\,\,\,\,\,\,\,||\,\,} 
\end{array}} \\ 
  {H – C – C – OH} \\ 
  {\,|\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,} \\ 
  {H\,\,\,\,\,\,\,\,\,\,\,\,\,\,} 
\end{array}$

$(ii)$  There are many structural isomers possible for bromopentane. Among them, the structures of three isomers are given.

$CH _{3} CH _{2} CH _{2} CH _{2} CH _{2} Br$ $\begin{array}{*{20}{c}}
  {\begin{array}{*{20}{c}}
  {\,H\,\,\,\,\,\,\,H\,\,\,\,\,\,H\,\,\,\,\,\,H\,\,\,\,\,\,\,H} \\ 
  {|\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,|} 
\end{array}} \\ 
  {H – C – C – C – C – C – Br} \\ 
  {\,\,|\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,|\,\,\,} \\ 
  {H\,\,\,\,\,\,\,H\,\,\,\,\,\,\,H\,\,\,\,\,\,\,H\,\,\,\,\,\,\,H\,} 
\end{array}$

$\begin{array}{*{20}{c}}
  {\begin{array}{*{20}{c}}
  {\,H\,\,\,\,\,\,\,H\,\,\,\,\,\,H\,\,\,\,\,\,H\,\,\,\,\,\,\,H} \\ 
  {|\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,|} 
\end{array}} \\ 
  {H – C – C – C – C – C – H} \\ 
  {\,\,|\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,|\,\,\,} \\ 
  {\,H\,\,\,\,\,\,\,H\,\,\,\,\,\,\,H\,\,\,\,\,\,\,Br\,\,\,\,\,\,H\,} 
\end{array}$

$\begin{array}{*{20}{c}}
  {\begin{array}{*{20}{c}}
  {\,H\,\,\,\,\,\,\,H\,\,\,\,\,\,H\,\,\,\,\,\,H\,\,\,\,\,\,\,H} \\ 
  {|\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,|} 
\end{array}} \\ 
  {H – C – C – C – C – C – H} \\ 
  {\,\,|\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,|\,\,\,\,\,\,\,\,\,\,\,|\,\,\,} \\ 
  {\,H\,\,\,\,\,\,\,H\,\,\,\,\,\,\,Br\,\,\,\,\,H\,\,\,\,\,\,H\,} 
\end{array}$