Oxidation number of Fe in Fe2(CO3)2

+2

Explanation:

Oxidation number of an element, also called its oxidation state, is the number of electrons its atoms lost or gain in the process of forming a chemical compound.

To determine the oxidation state of an element or compound;

- The sum of all the oxidation numbers in a neutral compound must equal zero (0).

In the compound: Fe2(CO3)2

This compound is a neutral one, hence, its oxidation state is equal to zero (0).

It contains a polyatomic ion (carbonate ion) i.e. CO3 2-, whose net charge is -2.

Hence, to find the oxidation number of Iron (Fe), which is represented by X, in the compound, we say;

X(2) + -2(2) = 0

2X + -4 = 0

2X - 4 = 0

2X = 4

X = +2

Therefore, the oxidation number of Fe in Fe2(CO3)2 is (+2)

The compound Fe2(CO3)2 is called Iron (II) carbonate

the electronic configuration of an atom with eight electrons is 1s²2s²2p⁴. the orbital diagrams are shown in the figure.

as per the hunds rule:

1. electrons tend to avoid being in the same orbital as per as practicable.

2. electrons in different orbitals of the same energy will have their spin parallel.

this can be illustrated from the multiplicity of the orbitals of the atom. as there are four electrons in the p orbital and p orbital has 3 sub-shells. the electrons can be fed in different ways as shown in the figure but the correct orbital diagram will be as per the hunds rule.