The metal complex that is diamagnetic is (Atomic number: $Fe = 26, Cu = 29$)

$(a) \ CoCl_{3} \cdot 4 NH_{3}$
$(b) \ CoCl_{3} \cdot 5 NH_{3}$
$(c) \ CoCl_{3} \cdot 6 NH_{3}$
$(d) \ CoCl(NO_{3})_{2} \cdot 5 NH_{3}$
Number of complex(es) which will exist in $cis-trans$ isomerism is/are ....

Consider the complex ions,$trans-[Co(en)_2Cl_2]^+$ $(A)$ and $cis-[Co(en)_2Cl_2]^+$ $(B)$. The correct statement regarding them is :

Match List-$I$ with List-$II$ :

List-$I$	List-$II$
$(a).$ $[Co(NH_3)_6][Cr(CN)_6]$	$(i).$ Linkage isomerism
$(b).$ $[Co(NH_3)_3(NO_2)_3]$	$(ii).$ Solvate isomerism
$(c).$ $[Cr(H_2O)_6]Cl_3$	$(iii).$ Coordination isomerism
$(d).$ $cis-[CrCl_2(ox)_2]^{3-}$	$(iv).$ Optical isomerism

Choose the correct answer from the options given below:

The complexes given below show:

Correct increasing order of spin magnetic moment $($in $B.M.)$ for the following complexes is:
$(I) \ [FeF_6]^{3-} \ (II) \ [V(H_2O)_6]^{2+} \ (III) \ [Fe(H_2O)_6]^{2+}$