Arrhenius acids are substances that increase the concentration of hydrogen ions (H⁺) in an aqueous solution. According to Svante Arrhenius, who proposed this theory in the late 19th century, these acids release H⁺ ions when dissolved in water. Common examples include hydrochloric acid (HCl) and sulfuric acid (H₂SO₄). In addition to producing H⁺ ions, Arrhenius acids typically have a sour taste and can conduct electricity in solution due to the presence of ions. They react with Arrhenius bases to form water and salts, demonstrating their role in acid-base neutralization reactions.