Determine the oxidation number for the indicated element in each of the following substances: a. S in SO2

Verified step by step guidance

1. Identify the oxidation number of oxygen, which is typically -2.
2. Let the oxidation number of sulfur (S) be x.
3. Write the equation for the sum of oxidation numbers in the compound SO2: x + 2(-2) = 0.
4. Simplify the equation: x - 4 = 0.
5. Solve for x to find the oxidation number of sulfur in SO2.

Key Concepts

Oxidation Number

The oxidation number, or oxidation state, is a theoretical charge assigned to an atom in a compound based on the assumption that electrons are completely transferred. It helps in understanding the electron distribution in molecules and is crucial for identifying redox reactions. Oxidation numbers can be positive, negative, or zero, depending on the atom's electron gain or loss.

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. These rules guide the determination of oxidation states in various substances.

Sulfur Dioxide (SO2)

Sulfur dioxide (SO2) is a chemical compound where sulfur is bonded to two oxygen atoms. To find the oxidation number of sulfur in SO2, one must consider the known oxidation state of oxygen, which is -2. Since there are two oxygen atoms, their total contribution is -4, leading to the conclusion that sulfur must have an oxidation number of +4 to balance the overall charge of the molecule to zero.