Chemistry Regents Practice Test 2026 - Free Chemistry Regents Practice Questions and Study Guide

The term "oxidation state" refers to the charge of an atom in a compound. It is a way to keep track of the electron ownership in chemical reactions and helps in understanding redox reactions. The oxidation state indicates how many electrons an atom has gained, lost, or shared when forming a compound.

For example, in a compound like NaCl, sodium has an oxidation state of +1, indicating it has lost one electron, while chlorine has an oxidation state of -1, indicating it has gained one electron. This concept is essential for balancing chemical equations and understanding the reactivity and properties of different substances.

In contrast, the number of protons in an atom refers to the atomic number, the total number of electrons simply describes the neutral state, and the bonding capacity of an atom relates to how many bonds it can form but does not directly define its oxidation state. Thus, understanding oxidation states allows chemists to predict and explain the behavior of elements in various chemical contexts.