Two solutions $\left( A \right)$ containing ${\rm{FeC}}{{\rm{l}}_3}\left( {aq} \right)$ and $\left( B \right)$ containing ${{\rm{K}}_4}\left[ {{\rm{Fe}}{{\left( {{\rm{CN}}} \right)}_6}} \right]$ are separated by semipermeable membrane as shown below. If ${\rm{FeC}}{{\rm{l}}_3}$ on reaction with ${{\rm{K}}_4}\left[ {{\rm{Fe}}{{\left( {{\rm{CN}}} \right)}_6}} \right]$, produces blue colour of ${\rm{F}}{{\rm{e}}_4}\left[ {{\rm{Fe}}{{\left( {{\rm{CN}}} \right)}_6}} \right]$, the blue colour will be noticed in :<br>