A Brønsted-Lowry base is defined as a substance that can accept protons (H⁺ ions) in a chemical reaction. This concept is part of the broader Brønsted-Lowry theory of acids and bases, which emphasizes the transfer of protons. When a base accepts a proton, it often forms a conjugate acid, which can then donate a proton in future reactions. In this theory, common examples of Brønsted-Lowry 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.