oxidation number

[Adam Kramer 1A]

is the oxidation number just the charge? If so, why do we now call it the oxidation number?

[romina_4C]

In a way it is the charge, but it more specifically is the number of electrons lost or gained by an atom. For example, in KCl, there is no charge on the overall molecule, but K has an oxidation number of +1 because it is donating one electron and Cl has an oxidation number of -1 because it is accepting an electron. If in a redox reaction there is a metal such as Mn2+, then its charge corresponds with its oxidation number.

[Izzie Capra 2E]

Many times, when you have a monoatomic ion, the oxidation number is just the charge. However, there are other cases when they are different. For example, when an element is in its standard state, the oxidation number is 0. And note that when you have a neutral molecule, the sum of the oxidation numbers of each atom must equal 0. If the molecule has a charge, then the sum of the oxidation numbers of each atom must equal that charge.

[Kavya Immadisetty 2B]

The oxidation number is the number of electrons that an element gains or loses when it makes a bond.