A Brønsted base is a substance that can accept protons (H⁺ ions) in a chemical reaction. This concept is part of the Brønsted-Lowry theory, which defines acids as proton donors and bases as proton acceptors. When a Brønsted base accepts a proton, it often forms a conjugate acid, which can then donate a proton in future reactions. Common examples of Brønsted bases include substances like ammonia (NH₃) and sodium hydroxide (NaOH). These bases play a crucial role in various chemical processes, including neutralization reactions, where they react with acids to form water and salts. Understanding Brønsted bases is essential in fields like chemistry and biochemistry.