[Cr(H$_2$O)$_6$]$^{3+}$

[Cr(H$_2$O)$_6$]$^{2+}$

[Mn(H$_2$O)$_6$]$^{2+}$

[Fe(H$_2$O)$_6$]$^{3+}$

${d^4}$

${d^8}$

${d^6}$

None of these

${\left[ {{\rm{CoC}}{{\rm{l}}_4}} \right]^{2 - }}$

${\left[ {{\rm{Co}}{{\left( {{{\rm{H}}_2}{\rm{O}}} \right)}_2}{\rm{C}}{{\rm{l}}_4}} \right]^{2 - }}$

${\left[ {{\rm{Co}}{{\left( {{{\rm{H}}_2}{\rm{O}}} \right)}_2}2{\rm{C}}{{\rm{l}}_4}} \right]^{2 - }}$

$\left[ {{\rm{Co}}{{\left( {{{\rm{H}}_2}{\rm{O}}} \right)}_4}{\rm{C}}{{\rm{l}}_2}} \right]$

$Ag$

$Ni$

$Cr$

$Zn$

Nature of the ligand

Oxidation state of the metal ion

Geometry of the complex

Temperature of the complex

Orange yellow

Orange

Green

Pink

${d^9}$

${d^7}$

${d^8}$

${d^4}$

The e_g set is lower in energy and the t_2g set is higher in energy.

The t_2g set is lower in energy and the e_g set is higher in energy.

Both e_g and t_2g sets are degenerate.

The d orbitals do not split in a tetrahedral field.

$t_{2g}^4\,e_g^2$

$t_{2g}^4\,e_g^1$

$t_{2g}^6\,e_g^0$

$t_{2g}^5\,e_g^1$

${\rm{C}}{{\rm{N}}^ - }$

${\rm{NO}}_2^ -$

${\rm{N}}{{\rm{H}}_3}$

$en$

A small crystal field splitting energy

A large crystal field splitting energy

No crystal field splitting

A distorted geometry