Which of the following pair is expected to exhibit the same colour in solution?

Step-by-step solution

In CuCl 2 , Cu 2+ has d 9 configuration, exhibit d-d transition and show colour. Similarly in VOCl 2 , V 4+ has d 1 configuration, can exhibit d-d transition and show colour. MnCl 2 = Pink colour Zn 2 + ⇒ 3d 1 0 Colourless Hg 2 + ⇒ 5d 1 0 Colourless V = 4 s 2 3 d 3 V 4 + = 4s 0 3d 1 (d - d transition) Cu +2   =   d 9 configuration = 1 - unpaired e − electrons. Since, in both CuCl 2 and VOCl 2 , Cu 2+ and V 4+ ion contain 1 unpaired electron each, so their colour may be same.