Determine the oxidation number of sulfur in each of the following substances: (f) Which region(s) of the periodic table contains elements that can adopt both positive and negative oxidation numbers?

Key Concepts

Oxidation Number

The oxidation number, or oxidation state, is a value assigned to an element in a compound that reflects its degree of oxidation or reduction. It indicates the number of electrons an atom can gain, lose, or share when forming chemical bonds. Oxidation numbers are crucial for understanding redox reactions and determining the electron flow in chemical processes.

Periodic Table Regions

The periodic table is organized into regions that reflect the properties of elements. Elements in the leftmost groups (alkali and alkaline earth metals) typically have positive oxidation states, while elements in the rightmost groups (nonmetals) can exhibit both positive and negative oxidation states. Transition metals also frequently show variable oxidation states, making them versatile in chemical reactions.

Electronegativity

Electronegativity is a measure of an atom's ability to attract and hold onto electrons in a chemical bond. Elements with high electronegativity, such as halogens, tend to gain electrons and adopt negative oxidation states, while those with low electronegativity, like alkali metals, tend to lose electrons and adopt positive oxidation states. Understanding electronegativity helps predict the oxidation states of elements in compounds.