Question

The charge on cobalt in \[{[Co{(CN)_6}]^{3 - }}\] is
A. -3
B. +3
C. -6
D. +6

Answer 1

Hint: We have to remember that the number which is assigned to a component within the chemical formula is understood because the oxidation number. The charge on the complex ion is adequate to the sum of the charges on the metal ion and their ligands.

Complete step by step answer:
We are given complex \[{[Co{(CN)_6}]^{3 - }}\]. We have to calculate the charge on the cobalt atom in this complex.
Central metal ion: central metal ion is Cobalt
Oxidation number: oxidation number is III
Coordination number: CN is bidentate ligand that is 6
Shape of the ion: structure is octahedral
Isomers: have optical isomer
IUPAC name: hexacyanocobaltate(III)ion
There are two types of ligands as follows;
Positive ligand: the ligand with positive charge that is +1. For instance, K is a positive ligand. Thus, the charge on the K ligand is +1.
Negative ligand: the ligand with negative charge that is -1. For instance, CN is a negative ligand. Thus, the charge on the CN ligand is -1.
Therefore, charge on the complex is,
Consider that the charge on the Co is X. Thus,
$X + 6 \times \left( { - 1} \right) = - 3$
$ \Rightarrow X - 6 = - 3$
$ \Rightarrow X = - 3 + 6$
On simplification we get,
$X = + 3$

So, the correct answer is Option B .

Note: Within the coordination sphere, the symbols of the ligand which follow the symbol of the metal atom are arranged alphabetically according to their names. This alphabetical arrangement is irrespective of the charge present on the ligands.
Now we can discuss about the properties of Coordination Compounds as,
The coordination intensifies framed by the progress components are shaded because of the presence of unpaired electrons that retain light in their electronic changes. For instance, the complex containing Iron (II) can show green and light green tones, yet the coordination mixes containing iron (III) have an earthy colored or yellowish-earthy colored tone.
At the point when the coordination community is a metal, the relating coordination buildings have an attractive nature because of the presence of unpaired electrons.