Question

How many ions are produced from $\left[ Co{{(N{{H}_{3}})}_{6}} \right]C{{l}_{3}}$ in solution? [RPET 1999]
(A) 6
(B) 4
(C) 3
(D) 2

Answer 1

Hint: An array of anions, or neutral molecules, are joined to a central atom by coordinate covalent bonds to form coordination compounds, which are chemical compounds. A coordination entity is a chemical compound in which the central ion or atom is bound to a certain number of atoms, molecules, or ions. The atoms or molecules attached to the central metal ion are known as ligands.

Complete answer:We should remember that the coordination entity does not break during ionisation, that is, the six $N{{H}_{3}}$ group remains attached to the cobalt metal atom even after ionisation. The ionisation of $\left[ Co{{(N{{H}_{3}})}_{6}} \right]C{{l}_{3}}$ is as shown below:

$\left[ Co{{(N{{H}_{3}})}_{6}} \right]C{{l}_{3}}\rightleftharpoons {{\left[ Co{{(N{{H}_{3}})}_{6}} \right]}^{3+}}+3C{{l}^{-}}$
During ionisation of$\left[ Co{{(N{{H}_{3}})}_{6}} \right]C{{l}_{3}}$, one ${{\left[ Co{{(N{{H}_{3}})}_{6}} \right]}^{3+}}$and three $C{{l}^{-}}$ ions are produced.
Thus, 4 ions are produced from $\left[ Co{{(N{{H}_{3}})}_{6}} \right]C{{l}_{3}}$ in solution.

Correct Option: (B) 4

Additional Information: This coordination compound $\left[ Co{{(N{{H}_{3}})}_{6}} \right]C{{l}_{3}}$ is optically inactive as all the ligands attached to $Co$are the same. It is diamagnetic in nature. This is because $N{{H}_{3}}$ is a strong ligand. It can induce a pairing of electrons, and thus it has no unpaired electrons left. It is yellow-orange in colour.

Note: Coordination compounds have a wide range of uses in analytical chemistry, including as catalysts for numerous industrial processes and in qualitative or quantitative chemical analysis. Coordination compounds have importance in biological chemistry. Coordination compounds are essential in the fields of health and metallurgy.