Among TiF 62-, CoF 62-, Cu 2 Cl 2 and NiCl 42- which are colourless species?

Question

Among TiF 62-, CoF 62-, Cu 2 Cl 2 and NiCl 42- which are colourless species? (A) Cu 2 Cl 2 and NiCl 42- (B) CoF 63- and NiCl 42- (C) CoF 63- and TiF 62- (D) TiF 62- and Cu 2 Cl 2

Tardigrade Admin · Accepted Answer

Among the given, Cu +in ( Cu 2 Cl 2) and Ti 4+ (in TiF 62- ) have no unpaired electrons. So, no d-d transition is possible. Hence, these two are colourless species.

Q. Among $T i F_{6}^{2 -}, C o F_{6}^{2 -}, C u_{2} C l_{2}$ and $N i C l_{4}^{2 -}$ which are colourless species?

$C u_{2} C l_{2}$ and $N i C l_{4}^{2 -}$

$C o F_{6}^{3 -}$ and $N i C l_{4}^{2 -}$

$C o F_{6}^{3 -}$ and $T i F_{6}^{2 -}$

$T i F_{6}^{2 -}$ and $C u_{2} C l_{2}$

Among the given, $C u^{+}$ in $(C u_{2} C l_{2})$ and $T i^{4 +}$ (in $T i F_{6}^{2 -}$ ) have no unpaired electrons. So, no $d - d$ transition is possible. Hence, these two are colourless species.

Q. Among TiF62−​,CoF62−​,Cu2​Cl2​ and NiCl42−​ which are colourless species?

Cu2​Cl2​ and NiCl42−​

CoF63−​ and NiCl42−​

CoF63−​ and TiF62−​

TiF62−​ and Cu2​Cl2​