Question

Which of the following is correct about oxidation number?

• A. The O.N. of all atoms in elementary states is 0
• B. Alkali and alkaline earth metals have +1 and +2 oxidation states respectively
• C. The O.N. of a monoatomic ion is the same as its charge
• D. All of the above

Answer 1

The correct option is D All of the above

The oxidation number of a monatomic ion is the same as its charge. E.g. $N{a}^{+}$, $A{l}^{+3}$, $S^{-2}$.
Option D is correct.