The correct representation of tetrahydroxidozincate (II) is:
1. \([Zn(OH)_4]^{2-}\)
2. \([Zn(OH)_4]^{-}\)
3. \([Zn(OH)_4]^{3-}\)
4. \([Zn(OH)_4]\)

$1.$ ${\mathrm{K}}_2\left[\mathrm{Cr}{\left({\mathrm{C}}_2{\mathrm{O}}_4\right)}_3\right]$
$2.$ ${\mathrm{K}}_3\left[\mathrm{Cr}{\left({\mathrm{C}}_2{\mathrm{O}}_4\right)}_3\right]$
$3.$ ${\mathrm{K}}_3\left[\mathrm{Cr}{\left({\mathrm{C}}_2{\mathrm{O}}_4\right)}_2\right]$
$4.$ ${\mathrm{K}}_2\left[\mathrm{Cr}{\left({\mathrm{C}}_2{\mathrm{O}}_4\right)}_4\right]$

The complex that is used as an anticancer agent is:

1. mer-[Co(NH₃)₃Cl₃         

2. cis-[PtCl₂(NH₃)₂]

3. cis-K₂[PtCl₂ Br₂]           

4. Na₂CoCl₄

A solution of [Ni(H₂O)₆]²⁺ is green, but a solution of [Ni(CN)₄]^2– is colorless because:

If 1/3rd of the total chlorine of the compound is precipitated by adding AgNO₃ to its aqueous solution, then the most likely structure of CrCl₃.6H₂O among the following is:

IUPAC name of [Pt(NH₃)₃(Br)(NO₂)Cl]Cl is:

Cobalt(III) chloride forms several octahedral complexes with ammonia.
A compound among the following that does not give a test for chloride ions with silver nitrate at 25 °C is:

The hypothetical complex
chlorodiaquatriamminecobalt(III) chloride can be
represented as:

1. $\left[\mathrm{CoCl}{\left({\mathrm{NH}}_3\right)}_3{\left({\mathrm{H}}_2\mathrm{O}\right)}_2\right]{\mathrm{Cl}}_2$

2. $\left[\mathrm{Co}{\left({\mathrm{NH}}_3\right)}_3\left({\mathrm{H}}_2\mathrm{O}\right){\mathrm{Cl}}_3\right]$

3. $\left[\mathrm{Co}{\left({\mathrm{NH}}_2\right)}_3{\left({\mathrm{H}}_2\mathrm{O}\right)}_2\mathrm{Cl}\right]$

4. $\left[\mathrm{Co}{\left({\mathrm{NH}}_3\right)}_3{\left({\mathrm{H}}_2\mathrm{O}\right)}_3{\mathrm{Cl}}_3\right]$

The IUPAC name of [\(\mathrm {C r \left(en\right)_{3}}\)]\(\mathrm{C l}_{3}\)${\mathrm{}}_{}$ is: