Sum of oxidation state (magnitude) and coordination number of cobalt in $$\mathrm{Na}\left[\mathrm{Co}(\mathrm{bpy}) \mathrm{Cl}_{4}\right]$$ is _________.

$$\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]^{3-}$$ should be an inner orbital complex. Ignoring the pairing energy, the value of crystal field stabilization energy for this complex is $$(-)$$ ____________ $$\Delta_{0}$$. (Nearest integer)

Total number of relatively more stable isomer(s) possible for octahedral complex $$\left[\mathrm{Cu}(\mathrm{en})_{2}(\mathrm{SCN})_{2}\right]$$ will be _________.

The conductivity of a solution of complex with formula $$\mathrm{CoCl}_{3}\left(\mathrm{NH}_{3}\right)_{4}$$ corresponds to 1 : 1 electrolyte, then the primary valency of central metal ion is __________.