Question

In $[Co{\left( {N{H_3}} \right)_6}]C{l_3}$ the number of covalent bond is:
A.3
B.6
C.9
D.18

Answer 1

We can calculate the covalent bonds by multiplying the number of bonds formed within the ligand and the total number of ligand molecules.

Complete step by step answer:
As we know coordination complex as a compound that consists of a central atom (ion) that is metallic and is known as the coordination centre. It is enclosed by array bound molecules (or) ions called ligands (or) complexing agents. Transition metals are coordination complexes. A coordination complex whose centre comprises a metal atom is called a metal complex of d block element.
We can draw the structure of $[Co{\left( {N{H_3}} \right)_6}]C{l_3}$ as,

In the complex $[Co{\left( {N{H_3}} \right)_6}]C{l_3}$ we can see that the central metal atom is cobalt and the ligands are $N{H_3}$ and chloride ions.
The covalent bonds could be calculated by multiplying the number of bonds formed within the ligand and the total number of ligand molecules.
The six molecules of $N{H_3}$ are linked to cobalt through six coordinate covalent bonds. Each $N{H_3}$ molecule is bonded to three atoms of hydrogen through covalent bonds.
The total number of ligand molecules is six and the number of bonds formed within $N{H_3}$ is three. Each nitrogen atom is linked with each hydrogen atom by three covalent bonds.
The total number of $N - H$ bonds is calculated as $6 \times 3 = 18$.
The number of covalent bonds in $[Co{\left( {N{H_3}} \right)_6}]C{l_3}$ is six.

So, the correct answer is Option D .

Note:
We must remember that the coordination compounds contain specific colours. Therefore, they are used in industries for intense colourations. Phthalocyanine is a class of coordination complexes that the dyes and pigments industry use.
EDTA is another complex compound that is used for determining the hardness of water. Coordination compounds could also be used as catalysts. These days, they are used in the polymer industry. Coordination compounds can be used in the extraction of metals from their ores. Extraction of nickel and cobalt by hydro-metallurgical processes requires a lot of complex ions.