Blue cobalt chloride paper gets its blue colour from ${\left[{\mathrm{CoCl}}_4\right]}^{2-}$ ions. Give the oxidation number of the cobalt in this complex.

Write the expression for stability constant for the given reaction:

${\left[{\mathrm{PtCl}}_4\right]}^{2-} + 2{\mathrm{NH}}_3 \rightleftharpoons {\mathrm{PtCl}}_2{\left({\mathrm{NH}}_3\right)}_2 + 2{\mathrm{Cl}}^{-}$

Write the expression for stability constant for the given reaction:

Write the expression for stability constant for the given reaction:

${\left[\mathrm{Ni}{\left({\mathrm{H}}_2\mathrm{O}\right)}_6\right]}^{2+}\left(\mathrm{aq}\right) + 4{\mathrm{NH}}_3\left(\mathrm{aq}\right) \rightleftharpoons {\left[\mathrm{Ni}{\left({\mathrm{NH}}_3\right)}_4{\left({\mathrm{H}}_2\mathrm{O}\right)}_4\right]}^{2+}\left(\mathrm{aq}\right) + 4{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)$