Question

Which of the following compounds are expected to show similar colour in aqueous medium?

• A. $FeC{l}_2$ and $CuC{l}_2$
• B. $VOC{l}_2$ and $CuC{l}_2$
• C. $VOC{l}_2$ and $FeC{l}_2$
• D. $FeC{l}_2$ and $MnC{l}_2$

Answer 1

The correct option is B $VOC{l}_2$ and $CuC{l}_2$

Metal ions having the same number of unpaired electrons in the d-subshell will show similar colour. Thus, $V^{4+}\left(3d^1\right)$ and $C{u}^{2+}\left(3d^9\right)$ will have same colour because of the same number of unpaired electrons i.e., 1.