Determine the oxidation number for the indicated element in each of the following substances: (d) N in HNO3

Key Concepts

Oxidation Number

The oxidation number, or oxidation state, is a theoretical charge assigned to an atom in a compound based on certain rules. It reflects the degree of oxidation of an atom and helps in understanding electron transfer in redox reactions. Oxidation numbers can be positive, negative, or zero, depending on the atom's electron configuration and bonding.

Rules for Assigning Oxidation Numbers

There are specific rules for assigning oxidation numbers, such as the fact that the oxidation number of an element in its elemental form is zero, and for monoatomic ions, it equals the charge of the ion. In compounds, hydrogen typically has an oxidation number of +1, oxygen usually has -2, and the sum of oxidation numbers in a neutral compound must equal zero.

Nitric Acid (HNO3) Structure

Nitric acid (HNO3) is a strong acid composed of one nitrogen atom, three oxygen atoms, and one hydrogen atom. In this compound, the nitrogen atom is bonded to three oxygen atoms, one of which is double-bonded, and the other two are single-bonded to oxygen and hydrogen. Understanding the molecular structure is essential for determining the oxidation state of nitrogen in HNO3.