Assign oxidation numbers to each element in the following ions. (d) NO2-

Verified step by step guidance

1. Identify the overall charge of the ion, which is -1 for NO_2^-.
2. Assign the oxidation number of oxygen as -2, which is typical for oxygen in most compounds.
3. Let the oxidation number of nitrogen be x.
4. Set up the equation based on the sum of oxidation numbers: x + 2(-2) = -1.
5. Solve the equation for x to find the oxidation number of nitrogen.

Key Concepts

Oxidation Numbers

Oxidation numbers are a way to keep track of electron transfer in chemical reactions. They represent the hypothetical charge an atom would have if all bonds were ionic. The rules for assigning oxidation numbers include that the oxidation number of an element in its elemental form is zero, and for monoatomic ions, it equals the charge of the ion.

Rules for Assigning Oxidation Numbers

There are specific rules for assigning oxidation numbers, such as oxygen typically having an oxidation number of -2, hydrogen being +1 when bonded to non-metals, and the sum of oxidation numbers in a neutral compound being zero or equal to the charge in a polyatomic ion. These rules help in determining the oxidation states of elements in compounds and ions.

Polyatomic Ions

Polyatomic ions are ions composed of two or more atoms that are covalently bonded and carry a net charge. In the case of the nitrite ion (NO2-), it consists of one nitrogen atom and two oxygen atoms, with an overall charge of -1. Understanding the structure and charge of polyatomic ions is essential for correctly assigning oxidation numbers to their constituent elements.