Question

To find the oxidation number for a molecule, you use the equation (# of valence electrons) - (# of credited electrons)

Ex- C2O

Valence electrons- 4

Credited electrons-3

4-3= 1

+I oxidation

What is a “credited” electron and how do you find them?

Answer 1

Credited electrons are those electrons that are either shared or donated by an atom to other atom,to which it is bonded.While calculating oxidation number,the bonds are all taken to be ionic,so that the hypothetical charge on the atom is called the oxidation state.For a neutral molecule the sum of the oxidation states or numbers of all the atoms is zero.

[In case of ionic bonding,these electrons are given off to the other atom ,so that the donated valence electrons from the atom occupies the partially filled valence shell of the other atom( thereby completely filling the later's valence shell ,thereby completing its octet state.

In case of covalent bonding ,the credited electrons are the shared electrons by the atoms,so that it occupies the valence shell of both the bonded atoms,completing octet electron for both of them.]

In case of CO (carbon monoxide)

Valence electrons of carbon =4

Credited electrons to oxygen= 2 (shared)

4 electrons are shared by oxygen to make a total of 6 shared electrons

oxidation number of C=+4-2= +2

+2 oxidation