Assign oxidation numbers to each element in the following ions. (b) SO3

Verified step by step guidance

1. Step 1: Understand the concept of oxidation numbers. Oxidation numbers are used to keep track of electrons in atoms during chemical reactions.
2. Step 2: Recall the general rules for assigning oxidation numbers. For example, the oxidation number of oxygen is usually -2.
3. Step 3: Identify the total charge of the ion. In this case, SO3 is a neutral molecule, so the sum of the oxidation numbers must equal 0.
4. Step 4: Assign the oxidation number to oxygen. Since there are three oxygen atoms and each has an oxidation number of -2, the total contribution from oxygen is 3(-2) = -6.
5. Step 5: Calculate the oxidation number of sulfur. Let the oxidation number of sulfur be x. Set up the equation x + (-6) = 0 and solve for x.

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, and hydrogen usually being +1. In compounds, the sum of oxidation numbers must equal the overall charge of the molecule or ion. For polyatomic ions, this rule helps in determining the oxidation states of individual elements.

Sulfite Ion (SO3)

The sulfite ion (SO3) consists of one sulfur atom and three oxygen atoms. To assign oxidation numbers in SO3, we start by assigning -2 to each oxygen, leading to a total of -6 from the three oxygens. The sulfur must then have an oxidation number of +4 to balance the overall charge of the ion, which is neutral.