The spin magnetic moment of cobalt in the compound $Hg[Co(SCN)_4]$ is (in $B.M.$)

Which of the following complex ions is not diamagnetic?

Which of the following is expected to be a paramagnetic complex?

The pair of metal ions that can give a spin-only magnetic moment of $3.9 \, BM$ for the complex $[M(H_2O)_6]Cl_2$ is

What is the magnetic moment of a divalent ion in aqueous solution if its atomic number is $28$ (in $BM$)?

The octahedral complex $[Co(NH_3)_5SO_4]Cl$ exists in two isomeric forms $X$ and $Y$. Isomer $X$ reacts with $AgNO_3$ to give a white precipitate,but does not react with $BaCl_2$. Isomer $Y$ gives a white precipitate with $BaCl_2$ but does not react with $AgNO_3$. Isomers $X$ and $Y$ are $.....$