The color of $[Ti(H_2O)_6]^{3+}$ is due to:

Which of the following is the correct order of increasing field strength of ligands to form coordination compounds?

Crystal field stabilization energy for high spin $d^4$ octahedral complex is

For which of the following pairs of complexes is the crystal field splitting energy $\Delta_0$ for $II > \Delta_0$ for $I$?

$I$	$II$
$(a). [Cr(H_2O)_6]^{2+}$	$[Cr(H_2O)_6]^{3+}$
$(b). [Fe(H_2O)_6]^{3+}$	$[Fe(CN)_6]^{3-}$
$(c). [Fe(CN)_6]^{3-}$	$[Ru(CN)_6]^{3-}$
$(d). [NiF_6]^{4-}$	$[NiF_6]^{2-}$

The crystal field splitting energy of $[Co(oxalate)_3]^{3-}$ complex is '$n$' times that of the $[Cr(oxalate)_3]^{3-}$ complex. Here '$n$' is [Assume $\Delta_0 \gg P$].

Why do transition elements form coloured compounds?