$[Co(C_2O_4)_3]^{3-}$ is a :

The number of isoelectronic species among $Sc^{3+}$, $Cr^{2+}$, $Mn^{3+}$, $Co^{3+}$, and $Fe^{3+}$ is $n$. If $n$ moles of $AgCl$ are formed during the reaction of the complex with the formula $CoCl_{3}(en)_{2}NH_{3}$ with excess $AgNO_{3}$, then the number of electrons present in the $t_{2g}$ orbital of the complex is . . . . . . .

The hybridization of the central atom in $NH_3, [PtCl_4]^{2-}, PCl_5$,and $BCl_3$ respectively is:

Which of the following complexes has its hybridisation correctly matched?

Hybridization in $[Ni(CO)_4]$ and $[Ni(CN)_4]^{2-}$ are respectively . . . . . . .

Statement $1$: $[Ti(H_2O)_6]^{4+}$ is coloured while $[Sc(H_2O)_6]^{3+}$ is colourless.
Statement $2$: $d-d$ transition is not possible in $[Sc(H_2O)_6]^{3+}$.