Give the oxidation state,
Question:

Give the oxidation state, d-orbital occupation and coordination number of the central metal ion in the following complexes:

(i) K3[Co(C2O4)3]

(ii) cis-[Cr(en)2Cl2]Cl

(iii) (NH4)2[CoF4]

(iv) [Mn(H2O)6]SO4

Solution:

(i) K3[Co(C2O4)3]

The central metal ion is Co.

Its coordination number is 6.

The oxidation state can be given as:

x − 6 = −3

x = + 3

The d orbital occupation for Co3+ is t2g6eg0.

(ii) cis-[Cr(en)2Cl2]Cl

The central metal ion is Cr.

The coordination number is 6.

The oxidation state can be given as:

+ 2(0) + 2(−1) = +1

x − 2 = +1

x = +3

The d orbital occupation for Cr3+ is t2g3.

(iii) (NH4)2[CoF4]

The central metal ion is Co.

The coordination number is 4.

The oxidation state can be given as:

x − 4 = −2

x = + 2

The d orbital occupation for Co2+ is eg4 t2g3.

(iv) [Mn(H2O)6]SO4

The central metal ion is Mn.

The coordination number is 6.

The oxidation state can be given as:

x + 0 = +2

x = +2

The d orbital occupation for Mn is t2g3 eg2.