Question

What is the algebraic sum of the individual oxidation numbers of all the atoms in the formula for a polyatomic ion?

A) Zero
B) The charge of the polyatomic ion
C) -1
D) +1

Answer 1

The algebraic sum of the individual oxidation numbers of all the atoms in the formula for a polyatomic ion is equal to the charge on the ion.

Step-by-step explanation:

The algebraic sum of the individual oxidation numbers of all the atoms in the formula for a polyatomic ion is equal to the charge on the ion. This is known as the oxidation number rule. For example, in the chlorate ion (ClO3), the oxidation number of chlorine (Cl) is +5, and the oxidation number of oxygen (O) is -2. The sum of these oxidation numbers (+5 + -2 + -2 + -2 = 0) is equal to the charge of the chlorate ion, which is 0.