Question

The sum of oxidation number of all the atoms in a neutral molecule must be zero.

• A. True
• B. False
• C. Ambiguous
• D. None of these

Answer 1

Answer: (A)

True

The sum of oxidation number of all the atoms in a neutral molecule must be zero.
For example, neutral molecules such as $O_2,P_4,O_3,S_8$ and $KMn{O}_4$ have the sum of oxidation number of all the atoms equal to zero.
For an ion, the sum of oxidation number of all the atoms is equal to the charge on the ion.
For example, in cyanide ion $\left(C{N}^{-}\right)$, the sum of oxidation number of all the atoms is equal to $-1$.
In ammonium ion $(N{H}_4{)}^{+}$, the sum of oxidation number of all the atoms is equal to $+1$.