Which of the following is a weak field ligand?

The crystal field stabilisation energy $(CFSE)$ and the spin-only magnetic moment in Bohr Magneton $(BM)$ for the complex $K_3[Fe(CN)_6]$ are,respectively

An ion $M^{2+}$ forms the complexes $[M(H_2O)_6]^{2+}$,$[M(en)_3]^{2+}$,and $[MBr_6]^{4-}$. Match the complex with the appropriate colour.

Why are low spin tetrahedral complexes not formed?

What will be the correct order for the wavelengths of absorption in the visible region for the following complexes: $[Ni(NO_{2})_{6}]^{4-}, [Ni(NH_{3})_{6}]^{2+}, [Ni(H_{2}O)_{6}]^{2+}$?

$\left[ Ti \left( H_{2} O \right)_{6} \right]^{3+}$ absorbs light of wavelength $498 \, nm$ during a $d-d$ transition. The octahedral splitting energy for the above complex is $....... \times 10^{-19} \, J$. (Round off to the Nearest Integer). Given: $h = 6.626 \times 10^{-34} \, Js$,$c = 3 \times 10^{8} \, ms^{-1}$.