Consider the following isomerism:
$i$. Ionization
$ii$. Hydrate
$iii$. Coordination
$iv$. Geometrical
$v$. Optical
Which of the above isomerisms are exhibited by $[Cr(NH_3)_2(OH)_2Cl_2]^-$?

Identify the diamagnetic octahedral complex ions from below $:$
$A. [Mn(CN)_6]^{3-}$
$B. [Co(NH_3)_6]^{3+}$
$C. [Fe(CN)_6]^{4-}$
$D. [Co(H_2O)_3F_3]$
Choose the correct answer from the options given below $:$

Which of the following is not correctly matched?

Which of the following complexes will show coordination isomerism?
$A. [Ag(NH_3)_2][Ag(CN)_2]$
$B. [Co(NH_3)_6][Cr(CN)_6]$
$C. [Co(NH_3)_6][Co(CN)_6]$
$D. [Fe(NH_3)_6][Co(CN)_6]$
$E. [Co(NH_3)_6][Fe(CN)_6]$
Choose the correct answer from the options given below:

Total number of unpaired electrons in the complex ions $[Co(NH_3)_6]^{3+}$ and $[NiCl_4]^{2-}$ is...............

The calculated spin-only magnetic moments of $K_3[Fe(OH)_6]$ and $K_4[Fe(OH)_6]$ respectively are $:$