proton donor

chemistry

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July 13, 2026

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In chemistry, an acid is defined as a species that has a tendency to lose a proton (H⁺). This concept is central to the Brønsted-Lowry theory, which states that an acid is a proton donor and a base is a proton acceptor. This definition is broader than earlier theories and applies to molecules and ions, not just substances dissolved in water. For example, acetic acid (CH₃CO₂H) can donate a proton to become an acetate ion (CH₃CO₂⁻), forming a conjugate acid-base pair. This proton transfer is fundamental to understanding many chemical reactions.123

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chemical compound
Classification of compounds
Thus, acids are defined as proton donors. The most common acids are aqueous solutions of HCl (hydrochloric acid), H₂SO₄ (sulfuric acid), HNO₃ (nitric acid), and H₃PO₄ (phosphoric acid). Bases, on the other hand, are proton acceptors. The most
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Thus, acids are defined as proton donors. The most common acids are aqueous solutions of HCl (hydrochloric acid), H₂SO₄ (sulfuric acid), HNO₃ (nitric acid), and H₃PO₄ (phosphoric acid). Bases, on the other hand, are proton acceptors. The most
Read More