Question

Co^2+ How can we come to know that 2+ is oxidation number or charge on atom ?​

Answer 1

Answer:

As we know that oxygen generally exists in a state having charge of -2

Charge on oxygen atom = -2

Also, we know that the total charge on any neutral compound is always zero and the total charge on any neutral compound will be equal to the sum of the charges on the substituent atoms.

Since, the total charge on any neutral compound  is$A_{x} B_{y} C_{z}$ given by

Total charge on the atom $A_{x} B_{y} C_{z}$= x(Charge on atom A) + y(Charge on atom B) + z(Charge on atom C)

But total charge on the neutral atom AxByCz is zero, we have

x(Charge on atom A) + y(Charge on atom B) + z(Charge on atom C) = 0

Using the above concept for the neutral compound CO2, we get

⇒ 1(Charge on C atom) + 2(Charge on O atom) = 0

⇒ Charge on C atom = -2(Charge on O atom)

By substituting Charge on O atom = -2 in the above equation, we get

⇒ Charge on C atom = -2(-2) = 4

So, the oxidation number of carbon in carbon dioxide (CO2) is +4.